Can't we make rebar out of plastic? Especially recycled plastic. It would solve two problems. It would not be as strong, but if made into tensioned nets it would have the same effect. I think it should be tested.
@@Metal0sopher Making anything out of reinforced concrete is an "art form" in my opinion. It requires, first up, a lot of consultation with the client about his budget, and a designer, architect/ engineer, and a builder with experience, and knowledge of how much the finished project will cost. then, all can consider the "alternative materials" and alternative shape of the structure. If the client is concerned about whether "Recycled materials" are being used, I tell them that a lot of rebar is made from re cycled rail way materials like axels and trunnions. and also that to my knowledge, all steel is made from about 50% recycled steel. Steel and concrete are good bedfellows, because they have the same coefficient of expansion and contraction.
I don't like the 'sustainable' movement since at its core, its full of people who want to justify wiping out large segments of the population. Its essentially a bourgeois movement that seeks to destroy anyone who's not part of the middle and upper-middle class bourgeoisie. This kind of ideology got out of hand in the past but, unlike back then, our modern technology would make the oppression far more effective.
The more I learn about building codes, zoning, and planning in the 20th and 21st Centuries, the less I respect the academic and professional discipline of "Professional Urban Planning". Urban planners have given us everything from urban sprawl to hideous and unsustainable buildings -- and then they have blamed their failures on the petroleum industry or builders or whomever. On the East Coast of the United States, storm water runoff and resultant flooding is a huge problem in the oldest cities. Yet those same cities and adjacent suburbs continue to allow -- and even require -- massive amounts of impermeable paving and building that merely increases the runoff exponentially. I am exasperated with planning/zoning departments and their degreed/certified "urban planners". They are the problem, not the solution.
Humanity would be better off without formal urban planning and architecture. The (human) cost of the occasional shoddy building is far lower than the cost of systemic failure.
The profession developed mostly in response to those same problems. In the absence of planners, people would be paving even more in the suburbs because it's where the demand is. The biggest failing of planners IMO is catering to commuters with their road decisions. It was a rearguard action that was never going to pay off.
@@josephfisher426 Response to those problems??? They gave the U.S. its worst problems. Urban planners devised the modern concept of dividing society into "residential, commercial, industrial". They bequeathed us a loathing of mixed use, and many (perhaps, MOST) municipalities in the United States STILL abhor mixed use in their zoning and planning. In suburbs from Washington, D.C. to Orange County, California, people have to get into their automobiles and drive miles to buy a litre of milk or a loaf of bread, or to buy a scone and a cup of coffee; that drive might be five minutes or it might be 45 minutes. It is no wonder that traffic is constantly terrible in Costa Mesa, Marietta, and Fairfax County. The demise of the neighborhood store or cafe was not merely a pity, it was an environmental catastrophe -- and still is. Only now are a few planning and zoning departments beginning to acknowledge it. But, in the mean time, planners and local governments have trained the populace to believe that the presence of any commercial entity in a residential zone is the end of property values there. Local residents will come shrieking with a whole host of "problems" (almost all of them perfectly solvable) at the first breath of anything commercial in their neighborhoods. It will be decades before any sort of mixed use is advocated as an antidote to the choking traffic of America's suburbs. American's have been socialised to believe in the segregation of "residential, commercial, industrial" -- a 1950's concept that was never even good in theory, and was a disaster in practice. Thank you, municipal planners. You sold us on the idea of suburbs, so now what?
@@billyungen Mixed-use zoning has been a fad in planning circles since the mid 80s, which was itself only about a decade after there was any real planning. Before that most development restriction outside of cities, which did necessary things like banning the keeping of pigs, came from covenants. Covenants aren't really enforceable now, but when land was recently enough subdivided that original purchasers were still a large proportion of the owners, they were assumed to be enforceable. That mixed-use zoning that was a fad has mostly not worked. It was inspired by older urban areas and it would be nice if it worked. But it's less efficient for business, in an environment with cheap energy costs, to operate in multiple locations as opposed to centralized ones that people drive to. Business is what ultimately chose the current arrangement.
@@josephfisher426 Mixed use "zoning" may be recent. "Zoning" is the operative word. But mixed use is thousands of years old. It has been around for thousands of years because it has great utility. Businesses and citizens today do what government planners allow them to do where government planners allow them to do it. They do not "choose" the current arrangement. Your post is poppycock. If businesses or citizens could chose where they do things, then we really WOULD NOT NEED planners.
How long should a computer last? Would you be happy with a computer with the capabilities that were available in most computers 15 or 20 years ago? How about your phone? Same question. The products around us are as durable as we demand, given all the other factors that go into a purchasing decision.
@@Monaleenian You would only be dissatisfied, because you have experienced the newer machines. In reality, how much better off are we, really? A 480p video on DVD without all the compression looks better than a 1080p streamed video, because the compression that is used to save bandwidth. Games, especially "AAA" ones, spend all the money on polygons and textures and not on actually being polished and fun. How much more productive are they? I don't build a new computer every 5 years because I want new stuff, I do it because the requirements for everything have bloated. For phones, it is even worse; it only lasts as long as the battery, which is generally no longer replaceable. The apps don't need better resources, and if I want a good camera, I'm going to get something waterproof and protected, not use my phone.
Great video. As a German, a specific project in my country comes to mind that fits this just perfectly: The city of Stuttgart decided to put their big train station below ground, and so they are currently building a new underground train hall with huge, wide reinforced concrete structures. Just constructing this is taking 15 years, and guess what? The planned lifespan of this structure is... 80 years. What happens then? Nobody knows. Problems for future generations.
Many a trillion dollars has been spent in recent decades on High Speed rail tracks that are built atop viaducts constructed of reinforced, epoxy bonded, post tensioned, peer cast, unique concrete segments, that are hopefully good for 40-60 years. That unlike 19th century viaducts can't be repaired with a few bricks and sacks of cement, over a few weekends, in half a century. The stations are but the tip of an iceberg.
@@the_aesthetic_city You failed to cover the ways that re bar can be protected to give a 200 year lifespan. Epoxy Coated re bar will likely last 100 years. Hot Dipped Galvanized re bar will last 200 years... So if premium concrete is used, with galvanized re bar, a 200 year lifespan is practical. Brick buildings don't last that long, unless they are designed to keep the brick about freezing [no insulation] and the building's mortar is repaired every decade. This is why the smaller buildings in the UK have lasted centuries, because essentially every wall has been rebuilt every century or so...
@@davidhollenshead4892indeed. Galvanized rebar and a good water proof concrete together with a adequate sealing of the building… and it will last 200+ years.
There are plenty of ways how to keep a concrete building stable. It starts from rebar protection, sacrificial anodes, electricity.. to carbon fibre reinforcements. In the tunnels most of the concrete is today shotcrete reinforced by Polypropylen fibres. A former employer of mine SIKA has an awful lot of solutions. I would not worry too much. The main challenge you are facing is the green ideology that aims for a poor feudalistic society. Such a society does not need roads or large railway stations. In a green society it becomes abundant. By the way the green rulers of Germany destroy the electricity generation (destroying modern coal plants, envroenmental friendly nukes and replace them by dirty useless solar panels). Trains need electricity to run.
It's amazing to me how mid-20th Century humanity collectively made all the wrong decisions possible. We traded sustainability, beauty, and urbanism that was once working wonders for everyone for greed, ugliness, and segregation. Even when the economic bubble is bursting and the planet is being rapidly destroyed for short-term profit, we still continue to destroy ourselves in name of greed and hatred for our fellow humans. It's sickening.
Happily there is an alternative - but it will be a battle to build better. We can only spread information, vote with our wallets, our feet and of course vote politically. But there is a lot we can do individually to spread the message!
They were busy making easily scalable designs, with low demand on skills. Democractic governments rarely support any long term expensive solutions fearing backlash from industry (less profit) and people (expensive goods). We are also resposible for it. for example, Building norms are designed for 50 years as most people do not want to live in older houses, prefering new houses meant to accomodate latest tech.
The real face of anti-Traditional architrcture: ugly, souless, short living, unefficient and enemy of the enviroment. Thank you for you videos, great as always
Not sure if you noticed, but the proposed solutions were not entirely traditional either. Plenty of traditional architecture burned down, fell over, or otherwise was destroyed under it's own incompetency in far shorter than 50 years.
@@gearandalthefirst7027 There's no match between traditional and modern. Where traditional was meant to endure it lasted centuries, where it wasn't meant to endure it was at least funcional and ecofriendly (like a wooden cabin house). The solution "not entirely traditional" still had to take the already existant knowledge as reference, while Modernism trashed it like it was just centuries of superstitions. Modernism was greatly moved by the hate for the old, rather than the improvement of things, thats the problem
We used to build buildings that could last 1000 years but many of them were ripped down after only being used for 40 or 50 years. An example of that would be Penn Station in New York. It was designed to last 1000 years but only stood for 53 years and was ripped down in 1963. Thousands of similar long lasting buildings met a similar fate. Modernism arose from the idea form followed function. It is wasteful to put a ton of resources into a building that will only be used for 50 years. If a building is only going to be used for 50 years then why design it to last a thousand?
Most buildings are built to whatever standard the owner can afford, the traditional buildings that last a thousand years are monuments that people have invested in to maintain. No ancient structures would exist if not for engineers and preservationists.
USA urban renewal of 69s did a lot of damage to cities especially on East coast many iconic buildings entire neighborhoods were razed. Salem MA downtown was devastated by soulless concrete replacements.
Fiberglass rebar or basalt fiber rebar is the answer to issues with steel reinforcement. It has many properties that are actually superior to steel and it will effectively last forever. Roman concrete had ash and clumps of unmixed lime that kept the concrete itself from eventually cracking and breaking down. Concrete is best used for foundations and slab floors where, if properly insulated, drained, and not on poor soil, it experiences only compression forces and is uniformly supported by the earth.
I work for a company that produces rebar out of duroplastics. These glass fibre rods are used in Bridges instead of steel rebar. It is resistant to corrosion, so the bridges won't need to be rebuilt every few years
@buddyrevell511 it is quite similar, yes. But the resin and the winding of the rebar might be a little different. Mostly because every company uses a little bit of a different approach to make their product unique. The company I work for specifically designed the product to the specifications and audits of bridges and other large infrastructure
Sounds like a very smart product! My bodycorp is managing spalling on a 1971-built poured reinforced with post-stress compression via internal cables. In about 2% by area, some 15cm in from the surface of exposed ledges, our rebar rusted. We are in Wellington NZ - windy and salty. It's usual maintenance around these parts; you'd need to build to ocean-going specs for slower degradation. Better concrete now than 50 yrs ago.
That sounds great, but I question it because of expansion. The reason why concrete and rebar work so well together (other than the flaws clearly laid out in this video) is that they expand and shrink at the exact same rate. How does your company deal with that? I'm genuinely curious
Modern architecture has been one of the greatest devil's bargains in history. Thanks for helping us to think about this. And you retain, not so much a sense of optimism but, resolve, that we must deal with this. I gave a lecture on texture that you might find interesting. Thanks. Let's find the ways out of this.
The fact that modern building codes disallow the use of unreinforced concrete is really something Edit: It seems I misremembered the codes, structural masonry is outright disallowed. Unreinforced concrete is restricted in its use but is still allowed in certain circumstances. I feel my point still stands, the building codes as they currently exist should be rewritten to embrace these types of construction. They are more sustainable than reinforced concrete and glass curtain wall facades.
One of the problems is that all the regulations that govern the construction industry are passed into law by politicians who know nothing about construction. So they get experts to draft all the legislation for them. To gain expertise, such people need to have worked in the industry. Thusly we get biased rules which assume that the methods in use are the only ones possible. It is also useful for the industry to avoid change because that has a huge cost, not only in innovating designs but in retraining workers and changing supply chains.
This is actually not completely true, within eurocode 2 which is used in Europe to design concrete structures there is a chapter about unreinforced concrete. However there are quite strict limitations to these as unreinforced concrete fails in a brittle fashion, giving occupants no time to get out of a building when it starts falling apart.
@@2mains234 the real problem is not the type of regulation, but rather the OBSESSION that everything MUST have rules governing it enforced by the government. this is the real evil.
@@MisterHeroman 1st of all: Lime-based concrete, hydraulic or non-hydraulic, is not a substitute for common concrete (PCC) used in construction today, which utilizes Portland cement as a binder. Lime constitutes 60-67% of raw materials consumed in Portland cement production. PCC is the second most consumed substance (right after water) in the world right now, as we speak. 2nd: Quartz sand is mostly used for decorative lime plaster, which is the smallest part of lime-based construction materials and should be preferably coarse - so neither river, nor beach sand are optimal. 3rd: Reinforced PCC should be, hopefully, replaced mostly by engineered wood in high-rise and infrastructure projects. 4th: You should do basic research on cob, adobe, lime stabilized earth etc. - you'll love it❤
I am studying civil engineering right now, and it is crazy how much of the lectures revolve around the use of reinforced concrete. I believe one of the main reasons for this is the fact that most people that want to construct buildings are wealthy people, and exactly those people do not think in a sustainable way, since this will not net them the most money. And i worry that since this is the case we will not really see huge changes in the near future. Tho brickwork is gaining a lot more popularity again especially for private contractors, and building with it makes it "only" 6-7% more expensive.
Yes there are many ways to design with other materials- they cost more, just like preventing rusting of the rebar, but we need to make a choice if we really want to be sustainable. Otherwise, we are just greenwashing or virtue signaling
If reinforced concrete is used for the floors and the roof is properly maintained... Why would it last only 50 years or even just 100 years? I don't like concrete as a finished surface of buildings either. But the dufference is very important and not adressed.
There's a lot of construction industries here in France which know how to built without concrete, since we still have building like that almost everywhere... Building methods aren't lost and the problem is not that they don't know but they don't want to change people aren't ready too to pay for a good and long time construction since it's much more expensive ..
@marblox9300 Well, it's sounds like a YOU problem, being annoyed at the way someone paragraphs their comments, lol. I find that funny as fuck. Especially coming from someone that uses a dash instead of a comma. Haha! (Double spaced paragraphs just for your enjoyment) Your comment just makes you look like a Richard Head.
"Building methods aren't lost and the problem is not that they don't know but they don't want to change people aren't ready too to pay for a good and long time construction since it's much more expensive .." I'm French and I disagree with that statement. A good and long time construction is not more expensive. In fact, it's the opposite. That's why buliding with clay, straw and so on (for example, using technics like they do with Kerterre) is not legal. Precisely because it's super easy to do and super cheap. But building is an industry and a market. And that means lobbies... Someone who buy a land and build a house in clay (for example) will not have the permit, even if everything is ok with the septic aspect and so on. Why ? Precisely because doing that, you don't pay those markets.
I can't believe it isn't common sense anymore to build buildings that won't degrade in a century. It's ridiculous, because in many European cities, the same people who build with this mindset are surrounded by buildings one and a half, two, sometimes even THREE centuries old. Thanks for the video
please take note that reinforced concrete hasn't been in the industry for that long. The estimate 50 year life span has considered multiple safety factors. Technically, they can even live more than a century. Those non reinforced concrete you have mentioned will easily collapse after an earthquake and kill people instantly. Not to mention the limitations these kind of structure have (you'd need bigger walls, bigger columns, that reduces your indoor space, goodluck finding a big lot for that)
There is an advantage in short lived buildings. Since there is no way to adapt a building to every technological innovation that comes by (think piped water and sewer, air conditioning etc), it's actually good that the building is cheap enough to build so that it can be torn down and another, more modern building is allowed to be built using the same piece of land.
@@tealkerberus748 It would not be too difficult to put these things behind access panels instead of burying them behind drywall. I'm surprised insurance companies don't insist on it. Problems with plumbing and electrical wires fester unseen inside walls, by the time the damage is noticed it is usually catastrophic; severe water damage, mold problems, electrical fires, etc. Stuff that is typically covered in home insurance and costs the insurance companies.
Urg the trend that is bugging me right now is in my home city we have a bunch of really nice red brick-clad buildings, and for whatever reason everyone feels the need to paint all the wood, brick, insides, furniture everything blank white. I'm so sick of white, it's the concrete color of the 21st century. White is nice, too much of it though is just painful. No color, we can't have color anymore, everything must be white. Then in front of these houses, they take the lawns and make them artificial turf because covering our organic lawns... in plastic is a great way to save the planet, don't have real plants just imitate them with plastic.
Lawns leaves in mass are able to produce oxygen which is very important in cities. Help absorb water and reduce erosion and flooding. They also have a cooling effect. The leaves breathe in CO2 and exhale O2. The carbon is in the roots. Mixed with trees plants and shrubs is very effective mitigation for the above reasons. They also help with noise pollution to a degree. Why you would want use plastic lawn is beyond me. Due to the processes and life span of concrete the cost isn’t really sustainable or effective. Resources are finite. While it may cost more for other construction in long run for the life of the building is cheaper and more likely to retain real estate values. These buildings even as shells from lack on maintenance especially on wooden and glass fixtures still go for millions in city areas to be rebuilt and redesigned into more modern architectural designs using different mediums. Personally I find it offensive to disrespect the architecture from the period the building was constructed in. There is a beauty in the old architectural designs that modernism and brutalism totally disregards.
It’s remarkable that buildings are typically planned with a lifespan of just 50 years. I hold the view that this approach is deliberately encouraged and endorsed by the influential figures of our world. Instead of seeking approval, we should forge ahead toward more sustainable practices without waiting for anyone’s sanction.
We have become a "throwaway society". Our municipal dumps are bursting full. Home appliances are not repaired - they're replaced. Automotive repairs are often replacement of entire modules. An expensive computer is discarded when one tiny soldered element fails. And so many buildings are torn down because they are "obsolete".
Another building material that is thrown away are tiles! Buy an old apartment and the buyer will surely tear the ‘old tile’ down and install ‘ modern’ design tiles…..however good condition the old tiles maybe…. ,
Another greatly underestimated material is just metal itself. There are plenty of metal alloys that are corrosion resistant so they last a very long time, and can be very beautiful as well, just look at historic cast iron facades. You'd keep the advantage of affordability too, since you can just press and stamp a large variety of beautiful shapes into metal plates, so there is no need for expensive artisans. Not to mention you don't need much of it since it's so strong, so less material has to be used and mined, and it's 100% recyclable as well so once it's produced it stays in circulation, plus you can process it with renewable energy. With proper interior insulation you don't have to worry about heat and sound either.
There have been studies into what it would take to replace our annual output of concrete buildings with steel. Likewise what it would take to replace them with timber. It was all wildly unfeasible.
@@tealkerberus748was thinking this. We would need massive deposits of iron ore, the type of supply we'd only get by mining Mars, which would be a conservation tragedy
The reason the pantheon still exists is that every generation since decided that this one building was worth preserving. The plain concrete developed large cracks had to be found and repaired to prevent collapse. It should be obvious that every building cannot receive such treatment.
I come from Singapore. It is a tropical costal city where almost our entire city is built of reinforced concrete. We have many buildings that are over 50 years old and most of our buildings are made of reinforced concrete. Concrete that is exposed to the elements is covered in plaster for vertical surfaces, to increase water resistance. For horizontal surfaces, we use waterproofing membranes below the plaster and slope the surfaces to drain and replace the waterproofing every 20 or so years. Our buildings are frequently inspected by structural engineers and many of the 50+ years old RC buildings are still standing. I thus suggest that you have exaggerated the problems posed by steel in reinforced concrete because there are solutions to prevent water ingress from causing rusting of rebars. Save for this one point, I agree with the rest of your points. I must admit though that we can’t see what’s happening below the soil to the foundations where RC is used extensively for pile caps, piles in some cases, contiguous bore pile walls, etc. However, if the foundations suffered from degradation of rebars from water ingress and rusting, we should expect to get cracking and gradual failure of the foundations together with a consequent subsidence and tilting of the buildings. This we have not seen.
YES! THANK YOU this is such bullshit and so easily solvable too: "The main cables of the Golden Gate Bridge can't be replaced, they have to be periodically painted and cared for exterior paint is really what protects the 80,000 miles of wire inside the cables from corroding," Currie said. Of course it's exaggerated...
Singapore never freezes. Where I live (northeast US) there can be hundreds of freeze/thaw cycles a year during winter months. The “native” architecture is traditionally wood with clapboard siding, steeply pitched roofs, and deep foundations that reach below the frost line. The wood requires maintenance but is pretty much immune to freezing and thawing damage.
His point still stands, because many places don't effectively maintain their buildings and infrastructure. Just because you are an exception to a rule doesn't disprove the rule.
More industry needs more people. Both needs more buildings. People need livable spaces. They need it as cheap as possible. These are the basic problems, modernists tried to solve. Arches and vaults need hight, stone and brick walls are thick. They mean less useable space in the building. Slabs are more cost effective made of steel, later of reinforced concrete, also walls. Ornament costs a lot, but is not "useful". (Beautiful, but who cares?) Modernists tried to make philosophy for the new material: "The beauty is the aestethic of structure". In some cases it is, but generally the investor is not interested, or there is no time to refine the plan, or the architect is not gifted or trained enough to make beautyful plans. Some architests are "artists" who make statues for themselfes... So that's what led to the overuse of reinforced concrete. Meanwhile the knowledge of making ornaments or vaults has been almost lost during 20th century. To build any form made of concrete is easy and builders have its knowledge. Making vaults need more time, makes more cost. The main drive force here is to build quick and cheap.
you are making an honest argument, but wasting your time here - the audience is a bunch of traditionalist snobs, who only care for their narrow privileged "visions".
The end of WW2 brought about all this “quick and cheap” short sighted ideas of reinforced concrete. So much needed to be rebuilt as fast as possible for little cost, so most countries went the short sighted route that is now having disastrous consequences on us.
@@alexsmith-ob3luwhat else could they do? Let people sleep on the streets? Specially with baby boom. You pretend like they had options specially countries hardest hit by the war.
Yeah, people nowadays seem out of touch with reality. We already have housing problems, ridiculous rent prices, etc, and they suggest we suddenly make construction 5x more expensive per square meter? I mean, I get it, we're apparently doomed if we don't quickly fix the environment, but come on, be realistic, you know? To be fair, bridges, dams and large public buildings such as train stations, for example, could indeed be constructed with arches. Build them to last. However, how do you build a 10 story or 20 story building with arches in a confined space? Good f'ing luck. I guess here the issue is that huge metrópoles shouldn't exist in the first place. Jobs would have to be more distributed in multiple cities so that the population density decreases, requiring less multistory buildings.
Another great episode. Also Roman concrete was a bit different and it has self repairing properties. Practical engineering channel has a great video about it 🙌🙌🙌
The ingredient you're talking about in 'Roman concrete' is quicklime. Concrete has that already. What makes roman concrete repair is the reaction with calcium in quicklime and the saltwater, thus calcifying and filling the gap. The issue with that is obviously that saltwater rusts rebar very, very quickly.
Does the limestone not get eroded? I studied a limestone landscape and the limestone is susceptible to be eroded by acid rain. Acid rain dissolves limestone because the limestone reacts with the rain to create calcite which is soluble. I only know about Karst landscapes though, is something done with buildings to make them less susceptible to this?
Retired engineer here.Concrete is the most versatile building material available. From sewers, tunnel liners to high rise buildings and bridges. Lessons learned are being applied to protect rebar from corrosion as one small example. Also the other main building material to frame a building is steel. That works in some places but not all. It’s all a matter of cost . Plus Buildings and infrastructure are needed urgently to serve a growing population . What is the quickest most efficient means to meet that need. As far as architectural beauty, that is partly related to what owners are willing to pay for the features. Plus the time to build. I agree many modern buildings, esp. residential complexes are rather ugly. But I don’t think the reason is the use of concrete . Anyways, concrete isn’t going anywhere. It’s here to stay. The engineering challenges are to make it last longer. Corrosion protection (coatings) and catholic protection are a couple of ways to mitigate rebar corrosion and extend service life of the structure.
Very well said! There is nothing worse than soul crushing concrete and your solutions sound pretty viable. Also, in Italy, even most of the "newer" buildings today are still built with arches, you can find them in the neighbourhoods built in the 1950s to 1980s in cities like Venice, Milan and so on. Now I wonder if the glass industry is causing similar problems for the environment, especially coupled with concrete...
Architect here. About carbon capture technology(CCT) - the NORM here in Norway, after grilling the concrete industry-representatives(Betonmast): they capture the CO2 with a filter at the factory, and put the pressurized co2 in tanks. These tanks are then shipped by truck to the coast, where they they are loaded onto ships, which are then.... dug into the seabed. Literally putting their problems in the silt.
@@mattllaves They've just figured out how to play the Co2 regulations so it looks good on the spreadsheet. There's alot of awareness and regulations being discussed to avoid greenwashing like that fortunately. Notably, there's an anti-greenwashing pledge that most architecture and engineering companies are part of, where they use other measures in addition to Co2 to measure sustainability. In 2021 we(the government) also implemented a 50-year rule for all new buildings, meaning they must last 50 years without serious maintenance. Most architects and engineers worth their salt are also aware that designing buildings that can be adapted to future changes in use and needs, be easily maintained, not to mention simply being beautiful will make any building last much longer.
Here's something that very few folks are talking about,; All plants and trees need Sea oh two to live. And very few folks know about what a miniscule percentage of our atmosphere is c 0 2. Trees and plants absolutely devour untolds of see oh too. And we spend a fortune dissolving it, (under pressure), into our drinks , no one likes flat beer or soft drinks. Would any University educated folks like to help me write and publish a book called "A hundred and one uses for si oh two".
Hello Aesthetic City, what are your thoughts on the return of murals to public spaces (particularly indoor public spaces) in newer classically-designed architecture? Murals, bringing a painted form of life, emotion, and beauty to public and common spaces, were quite common in older, classically and traditionally-designed buildings, but don’t seem to be too common in newer classical/traditional buildings nowadays.
So use nature's ultimate, infinitely renewable engineering material: wood. There are plenty of 500 year old wooden structures still standing because repairs are easy and it's really damn strong. We don't need 50-storey high-rise apartments if office work isn't concentrating all the jobs in 50-storey office buildings
Ok no, first of all. If this is a problem you think nobody is talking about, it's because you're not related to the engineering and construction world. And if you are not indeed related to that field, I understand the existence of the video, because it's pretty uninformed. For all the problems you described, there are a lot of ways to avoid/solve them, to the point that it's 100% the builders to blame. For freezing conditions you have additives, for coastal buildings you have noncorrosive steel, additives that close the pores of concrete, special paintings. For alcali the only solution i know of is to choose the right materials beforehand, it's something that's not common at all in my area. All pathologies have been studied, documented, analyzed. There are a lot of publications of a lot of laboratories and professionals that investigate how to solve them. None of them is a "dark true" or "something not talked about". It is extremely important that professionals are well trained in the material. That's the main reason of all the pathologies associated with reinforced concrete. Just don't blame the material for the errors of the builders. If contractors in your area build poorly, denounce them, not their field.
@@uisgeuisce Re. the two previous comments; Non tradesmen are welcome to talk all they like about how producing cement produces more sea oh too than aviation. I don't believe THAT for a moment. Repair folks call the problem of rebar rusting "Concrete Cancer". If rebar is covered with enough concrete, our atmosphere cant harm it, also there is just so many way to extend the life of structures made of rc Concrete, i'd take a month to explain it. I thing you two guys sound like you have some "real world experience", in the building and construction industry. Time is valuable, so I'm gunna leave the discussion to the university educated folks to have a text book talkfest.
@@benjigray8690 no idea why you are replying to me and what's your point. I'm an architect and this channel is not sincere in his analysis to the point of making shit up. Don't have time either to lecture people on the internet.
The fact remains. All modern steel-reinforced bridges have a maximum lifespan of 50 years. That just sucks. Might as well not build them at all, at that failure rate. Yes, we know it's a flawed product, but we will go ahead and build it anyway.
@@shanemedlin9400 50 to 100 years at least if done and maintained properly. Well next time it happens you get to use a bridge or highway please don't. Or even better! Come up with an alternative to it you may as well become a billionaire!
0:11 LOL BS...the concrete should not be destroyed and replaced..when you say renovation and demolition, it happens when you want to build a more profitable building on the respective land. In many cases, the blocks are located in areas with extraordinarily expensive land, which is why they are being torn down and the respective concrete is recycled into other building aggregates...I live in Eastern Europe and I own several apartments in these concrete blocks and I even invested in brand NEW apartments recently built of brick with a concrete frame that are inferior to the old 100% concrete buildings. Not even on the seashore, where salt is a major factor of damage, does it cause problems for the blocks to be demolished. This video refers to the blocks made by Americans with very weak cement in no case to the old European blocks that have been standing for 100 years without a problem and that will stand for many generations to come
I do really hope you're right on that one. First because it would be so dramatic to imagine that all the concrete buildings are at major risk to just fall off with all the people who could die in this process... Second - very more minor aspect - concrete house are the only affordable houses in my budget in France (all the concrete houses from the 60's and 70's). So if I buy one, I hope I can keep it for at least 50 years more...
The building material of the future will be melted rock - by _sintering_ stone into a basalt like agglomerate we can create almost indestructible bricks in any shape imaginable. By assembling these bricks on site acording to computer aided design, you can erect extremely longlasting and absolutely beautiful structures by fitting these tgogether as Lego blocks - which allows deassembly and recycling blocks in the future. Variants of this asembly of hyperdurable rock components are 3D printing sintering desert sand thrugh a freznel lens - as wonderfully evidenced my Marcus Kayser.
I believe this is the plan with constructing habitats on the Moon, and eventually Mars. By cooking the regolith we will be able to fly there with less materials, making it more cost efficient, among other benefits.
Civil engineer here! Great video! Corrosion is a huge problem for us right now. People have not realized that when they were building with concrete in the 70s or the 80s, they where building for approximately a 40 year lifespan. Now everyone is in denial they either need to either tear it down or spent a fortune to retrofit it.
Great video. I already dislike the look of concrete buildings, but I had no idea they were so impractical as well. Love the visual presentation of your videos as well, and I'm glad to see you're comitting to your unique illustrated visual style. They're not just fun and stylised, but their simplicity also helps make the more complex explanations (such as how the rebars can get rusty) easier to comprehend.
rebar in concrete used in buildings isn't really susceptible to corrosion anymore than steel beams are. rebar corrosion is only really a issue for concrete exposed to weather.
@@Khanfuzed1 For many applications fiber reinforced concrete is similar to steel reinforced concrete. However, many of the fiber approaches give me strong asbestos vibes.
@@Mooooov0815 To be fair, if even asbestos was embedded deeply in concrete (and never exposed), it would be fine. It's when it powderizes and gets into the air that the mesothelioma can-can starts.
The rust thing is a non-issue in most buildings because they use rebar that's already rusted which is then covered in concrete. The problem with rust is that it is very fragile, but otherwise it's a very good protective layer. Rust is a non issue once covered in concrete because concrete protects it thus counteracting rust's fragility
Noting that pink rebar (made of fiberglass) is stronger, lighter, cheaper, won’t corrode and it’s a fun color. Sodium bicarbonate can be added to dry mix to reduce the c02 emissions of concrete as it cures, and in the cement manufacturing process, the heat used to make the portlandite can be reclaimed to generate electricity. Same with the emissions. It just requires government legislation to do so.
Concrete doesn't release carbon dioxide as it cures. It absorbs it. All the carbon dioxide that was baked out in the process of making portland cement will eventually be absorbed by the concrete in the process of curing.
Excellent video! I just discovered this channel. I've been involved in sustainable and circular construction for many years. In 2011 I became project manager of the Dutch Concrete Green Deal. This was an industry initative to find out how we could make the concrete sector more sustainable and set up a deal to make it happen. In 2016 the deal (with the Dutch Government) was formalized ("Beton Akkoord"). Unfortunately I'm not so happy with the speed at which the changes are happening, but the sector has definitely changed in my country, using a lot of recent and less recent innovations to lower their carbon emissions (which were already the lowest in the world per m3 of concrete when we started out), and increase the use of secondary materials. I can mention several options which have not been mentioned in the video, but there's 2 very promising ones to add in the comments: 1. Reinforcing concrete with basalt rebars. This gets rid of the problem of rust limiting the lifespan of concrete to 50 years or so. There are still one or two challenges to overcome for this fantastic material, but it holds great promise. There are other options as well (like fibreglass) but they also have their challenges. 2. Closed loop recycling using the 'smart crusher and similar technology. Current standard recycling technology is able to recycle part of the concrete as an aggregate alternative. This works fine for less demanding types of concrete (like pavement blocks and such), but is limited when it comes to concrete for flooring or infrastructure. More important is that this recycling technology is not very good at producing a substitute for sand in concrete. The innovative 'Smart crusher' is capable of producing very clean gravel and sand products that are comparable to the original material and can be used for high quality concrete. The remaining cement/ fines fraction is more difficult to recycle, but Heidelberg is working on using this reactive material after further grinding as an additive to cement. Currently the demand for concrete is quite a lot larger than the amounts of concrete that are 'harvested' from demolition, so recycling can only lower the demand for primary resources, in the Netherlands a maximum of about 25 - 30%. But it can certainly help, in particular the demand for sand. What I very much like about the video is the idea of building for longetivity. Not 50 years but a 1000! This is an important goal for circular construction, both for buildings (and infrastructure by the way) and for construction products. Sometimes a shorter life span is preferable because it is unavoidable that the required functionality is going to change, and built in adaptivity is not possible. Then re-use of construction products and elements are possibly a better option. Instead of a construction with a long lifespan you create construction products with a long life span. I was involved in the design of a circular viaduct which was based on modular blocks that can be reused many times over a projected minimum life span of 200 years. You also mention the importance of standards (which you call 'norms' - a word which in English has a slightly different meaning, but I'm sure you mean 'standards'). I am currently chairman of a new working group within CEN (the European standardisation institute) that is developing a standard for circular design in construction. This will lead to technical requirements for both constructions and construction products including aspects like lifespan, adaptivity, maintainability, reparability, detachability/ deconstructability, reusability and (closed loop) recyclability. Let me know if you are interested: you can find me on Linked in (Evert Schut). Or - if you are situated in Europe - you can contact your national standardisation institute to join us.
@@0MoTheG If the steel isn't embedded in the masonry it's not going to work the same way. I think we need to completely re-engineer how we do concrete. Purely compressive design with no reinforcing isn't the way, and mild steel reinforcing that rusts within a century isn't the way either. People are using basalt fibre with good effect where it's properly engineered, but it you get it wrong you have a concrete structure that fails without warning - one of the advantages of steel reinforcing is that the concrete can fail and you'll see it crack and sag but the steel holds it together long enough to evacuate the building. Getting that feature with non-rustable internal reinforcing is easier said than done, but that's what we need to do.
4:52 just to be used stainless steel for the inforced concrete and the buildings can upstand dor 250 up to 1000s years, depends on the stainless steel properties. 😎
Concrete buildings have a average life span of about 300 to 500 years. (average doesn't say anything beside it is always longer than 300 years) The concrete is only filling, what keeps the building up right are the metal beams within the concrete. Even if you take all the concrete away the building will still remain upright from its metal skeleton alone.
There are some products for reinforcement that can be used in the short term during the transition such as epoxy coated rebar or fiberglass rebar, but you are right going back to the old materials would be very beneficial except for very tall buildings where it would not be as practical. Good video.
This video is truly misleading. Non-reinforced concrete buildings indeed demand exponentially more concrete volume compared to their reinforced counterparts. This oversight leads to a ripple effect of increased carbon emissions, heightened sand mining, and escalated carbon emissions from transportation due to the excess materials required. Moreover, the economic and affordability aspects cannot be ignored. Constructing a building to endure for millennia, not just a century, is admirable, but when it necessitates ten times the materials, it raises serious sustainability concerns. Of course, concrete is a major carbon emission contributor and we should do more research to mitigate its environmental impact. However, opting for non-reinforced concrete, especially using existing common concrete, is not a wise idea. Consider the hypothetical scenarios: If all reinforced concrete buildings were constructed using non-reinforced concrete, akin to ancient Roman practices as the video suggests, the current atmospheric carbon levels would undoubtedly reach catastrophic levels. Alternatively, envisioning a world where all reinforced concrete buildings were replaced with timber structures highlights the peril of excessive deforestation. Yes, concrete emits lots of carbon, but concrete is not the enemy. We managed to reduce carbon emissions to these levels and use less resources while facilitating shelter to the people thanks to the concrete. However, carbon capturing in the cement-making process, and alternative less carbon-emitting innovative materials are some actual answers to reducing the impact.
I think 50 years is simply not true there are brutalist buildings in my city made from exposed concrete blocks, that are already over 80 years old, they seem to be still structually sound althought you can see some deterioration. There are many concrete buildings around Europe which are 200+ years old and stand perfectly. Newer buildings that are done with European standards have insulation that further protect the concrete from outside influences, these buildings will definitely last longer than 50 years.. also to finish most buildings aren’t only supported by outside walls, they have massive pillars inside the building which hold the weight and they can’t possibly deteriorate fast because they experience no outside influences.
My issue with concrete is that the building is homogenous and thus construction has to be continuous. If only it was more modular, then you can just replace the elements individually. Thankfully, there is precast concrete where you can just remove only the damaged portion instead of destroying the entire structure. Of course, depending on the structure, mileage can vary.
12:03 Why the would steal the sand of beaches? you mentioned in just 5 second earlier that only river sands can be used for concrete for their rough edges.
reinforced concrete structure can be also long standing, even for thousands of year with proper design and construction, with protection against moisture, that other buildings cannot tolerate either, (wood will rot and develop mold, stone can be also ruinned by frost cycles..etc.). Cement is one of the most useful binding materials we have to house milliards of people..there is not enough stone caves or pyramids to house 8 milliard people..the burning of bricks also need energy..adn there is Ytong, a lime based cement structure..
As you said the CO2 from portland cement comes from the CO2 released when burning lime, it's weird to not mention that this CO2 is reabsorbed when it sets (called the lime cycle.)
One of the reasons our quality of life is so much greater than that of the Romans is that we have massively reduced the cost of building. And this is undoubtedly because of reinforced concrete. Enforcing a rule to design buildings to last 1000 years may sound like a good idea on the surface but it would increase the cost of living in general, by a massive amount. It would also result in many projects not being funded as they would cost so much.
Long term we should be looking at materials such as basalt, no CO2 reaction to worry about! This would require new building regs so not a short term solution. For now I like the idea just using stone and craftsmanship!
Concrete itself should be replaced by something which is better than it, not that we know about any alternative right now. But concrete is highly problematic, it's not that strong either.
Great video! Very interesting subject that we learn about in architecture school but that civil engineers don't care about. I'm a dual-trained architect and engineer, and this question of a return to geometry in the natural order has been on my mind... The question is how to introduce these more reasonable construction methods into a capitalist system that relies solely on short-term profit? We still have a lot of work to do in this direction...
On one hand you are totally right, the massive and often crude use of concrete is a big problem nowadays. But on the other hand you aren't considering the reallity of much of those buildings: Many of them were build when millions of people needed homes. If millions of people search for living spaces it's a much better idea to build an appartment block where thousand people can find shelter than building a dozen single family houses for some dozen people! So it's true that they could have been build in a more sustainable way but two story family houses aren't the solution either.
I'm afraid building to last 1000 years instead of 50 is greatly incompatible with the economic systems we have in place. They depend on deterioration of things to keep money flowing
Every building material with the exception of wood, comes from a whole in the ground. Not using reinforced concrete leads to using more building materials. So it's not that straight forward. Also the CO2 that is emitted by making cement, from the chemical reaction, is absorbed when the concrete sets. So I don't think that's the biggest issue.
Well, living in reinforced concrete structures is not so common in Germany and probably not so common in much of Europe. Individual houses are built from brick (Poroton thermal clay blocks for example) and much of apartment housing for rent up to 4 floors uses such porous bricks as well or lime-sand-brick (Kalksandstein) for the structure and decorative clay bricks for the facade. Outside of earthquake zones, reinforced concrete is rarely used for low-set residential structures. Only high rise apartments and public/commercial buildings use reinforced concrete a lot. Modern basements and floor slabs are usually made from reinforced concrete though. My grandfather's house, with wooden floors, lasted from the 1930's to the 1980's with minimal renovations. Since then many things have been refreshed and new materials have been introduced, but the structure is basically the same. It will certainly last over a hundred years, but probably needs to be thoroughly rehabilitated every 40 to 50 years. Whether those highly insulated modern residential structures last more than 50 to 75 years is doubtful as well though, due to the complexity of modern building systems which often include foil layers for air proofing and water proofing and polystyrene on the outside of the facade. The wall structure could possibly last more than 100 years, if the modern thin mortar-glue for the insulating Poroton blocks lasts that long., but heating systems, plumbing, electrical systems, roof and wall insulations all expire much faster than reinforced concrete.
Having studied civil engineering myself, it's so uncanny that RCC is considered the primary building material for almost every structure and all codes somehow revolve around it. I come from the Himalayas and the primary building technique used here traditionally is stone masonry. However, I find them structurally very weak in lateral loading due to earthworms as this region comes under seismic zon 4 or 5. The codes recommend RCC. Personally, I also feel there's no other way except RCC in this case. All we can do is minimise the use of concrete but can't get away from it completely.
I am glad that increasingly more US construction is conducted with OSB. This material is a wood material that is arranged into square or rectangular panels and structurally strong, regardless of the direction of the grain of wood that is used to manufacture it. so long as it is kept away from water, it is a very robust material that survives well in terms of earthquakes. This material is also relatively easy to treat to improve fire resistance.
OSB construction is the bane of firefighters because it burns fast and it is toxic and has a short lifespan. I suspect the above comment is from a bot.
By way of observation amongst the people in my life, both sides of the spectrum, I find most post-modernist artsy-fartsy types are fairly left-leaning and with this video, you are convincing them their less-than-lovely, preferred styles are actually unsustainable. For some people who love their brutalism or the 'cult of the ego' style buildings, this argument to choose alternatives to concrete may cause cognitive dissonance in many, leading to some who might... just might actually have to accept that their beloved 'beauty is in the eye of beholder' monstrosity is hurting the environment and cheap materials that form our cityscapes lead to eventual 'dis'function. Me, personally I love this argument and whole heartedly would love to see a renewal in beauty in architecture. A revival of beauty is necessary for the sake of humanity's soul. As such, I am convinced even more and have learned a great deal. Dank u wel. As for the above-mentioned types, the questions remains: will facts win over entrenched feelings? These days, I can hope but I never hold my breath.
In the Uk they are building a new railway called HS2. The bridges and viaducts are almost exclusively reinforced concrete. How long will they last I ask ? I walk in Derbyshire and see stone built railway viaducts and bridges still in use after 180 years and some canal bridges that are nearer 250 years old. Were they not a good investment? Some other bridges constructed in the 1960s are now in serious need of repair as the corroding re-bar has "blown off" the surrounding concrete. Short terminism is to blame! Excellent vid highlights these issues, but I suspect greed conquers all ?
@@the_aesthetic_cityAnd how these buildings get both cold in winter and hot in summer and thus are very energy-intensive. They didn't care about that in the 50s and 60s but somehow architects keep building them to this day.
What a great video, in the architecture course there is not much mention of the disadvantages of reinforced concrete or other solutions like the ones in the video.
One thing that is rarely considered is the use of pumped concrete. The amount of water that is needed to set concrete is so little that it is far to stiff to be placed in moulds and to make adequate contact with the rebar. Adding more water makes very fine voids in the concrete when it eventually dries out (long after setting). This allows water and oxygen to be carried to the steel, promoting corrosion and spalling of the reinforced concrete.
Uhmm some key points 1. Ancient magnificent structures took as many as 2 -3 generations to build and with massive slave labor. 2. Materials used were more redly available. 3. To build such structures today would run into trillions of dollars. 4. Extremely less functional per square foot use of space 5. Mold mold and more mold. Horrid health hazards 6. The ones still standing are mostly historic attractions that have had millions and millions of dollars spent to maintain them. They crack and fall apart, foundations give out and mostly poor designs for weather protection. 7. What he or the bot said about steel reinforcement corrosion was correct. Except today the rebar is coated with anti corrosive materiel. 8. A concrete design is only as good as its installers and inspectors. The more people in the world, the more corrupt and incompetent, yet still only about 5% in every type of work. 9. Iv'e worked with structures for 50 years both new and restoration of old. I studied ancient architectures in college. Yes, they are magnificent beautiful works of art. But nothing that modern man has the resources to economically build today. Some materials no longer even exist that they used in some of those magnificent cathedrals.
Something i do not understand is why we do not use more recycled polymers, considering that most of the plastic is not recycled because of purity problems making it unusable for food packaging , but that post polymers have quite a decent weight to tensile strengh ratio, even recycled stuff, and on top of that would be made of garbage (so, the process of harvesting it would have a double use: cleaning environment and scavenging raw material sources ). I m especially thinking about polyethylene and polypropylene , like, imagine using some recycled HDPE and PP pieces in the same say wood was used traditionally, We could also potebtially find an use for the desert sand that is too smooth for concrete by sintering it into solid glass-like bricks (heat treated glass can have a better impact resistance than unreinforced concrete) or by fully melting and processing it into fiberglass (fiberglass , even in the E form has above 3 gpa of UTS, so, it absolutely beat reinforced concrete s tensile strength in cartoonish proportions ) Especially when we consider glass s very high chemical resilience , abrasion resistance and recyclability (and we can either let it be transparent or make it opaque by adding things inside) Like, imagine using the desert sand to make fiberglass, and then process recycled plastics into a matrix for such fibers and creating a low cost version of fiberglass composite for buildings (and the for part that need the focus on compressive strengh using heat treated glass bricks ) we could have something much stronger that still allow the same ease of design as concrete (probably more actually ) while having much superior durability
Very eye opening video! I worked for a company that built kilns and furnaces using angle iron frames to support high temperature concrete structures. For the disk shaped lids of crucible furnaces which were less than 4 inches thick, we used stainless steel fiber mixed into the castings concrete. The cured pieces were extremely tough and they could withstand hundreds of strikes from a sledge hammer. I had to break a lid out of its frame once because of a dimensional mistake and the effort needed was amazingly intence.
9:26 - yeah, after the last war. Before that, with modern weapon systems any structure is nothing else but a target for a missile. Why one would spend a fortune on single building that can last a century if same money can be spend to build entire city?
Main difference I can think of is the steel used in modern concrete, which definitely will rust over a certain period. Ancient buildings like the pantheon didn't used it, as far as I know. Well honestly I guessed but I never heard of any giant roof renovation of the pantheon. Funny to ask before the video is online 🤣 But yeah I am also keen to see more of this beautiful made content
Steel reinforced concrete faces rust issues when the steel becomes exposed. This puts a life expectancy on all reinforced concrete. Unreinforced concrete can, in theory, last forever.
This is all good and well, but noone talks about the price. Construction with such tech will cost x5/x10 the current price. And noone is gonna go for it for economical reasons - this is just isn't worth it. It can be worth "globally" but noone is planning ahead for hundreds of years. And yes, this will require much more manual and highghly qualified labor, which is getting more and more expensive every day.
Fantastic video! Besides all the ecological and structural problems of the concrete the buildings are built of today it is indeed a very unappealing looking material. Especially when it comes to brutalist or in some ways also contemporary architecture. Anyway, continue your great work!
I kind of know, that in realistic and economical sense, and with current population, concrete/steel is kind of essential to house all production and infrastructure (and even despite that, there is housing price issues as well). And despite the video being pretty biased against modernism and not mentioning the downsides of natural materials and techniques of buildings, that are longer/more expensive to build, not as effective at insulation+installation of commodities like water and electricity, and not even mentioning the changed modern view and lifestyle, focusing less on cultural values and more on efficiency, and even using unlivable pavilion as example as well... I still admire the spirit.
Modernist philosophy of architecture is more of a problem than cons of reinforced concrete, and that philosophy also influenced modern design standards. Reinforced concrete definitely has it's problems, but you can't advocate for old building techniques without considering earthquake, soil conditions etc. It can be very misleading for architects and investors to think they can build unreinforced masonry building in seismic area. You cannot economically design for earthquake loads and expect no (high) tension forces in your structure. Not to mention load distribution through diaphragms, uneven settlement of foundations etc. Reinforced concrete enables relatively simple and cheap earthquake resistant buildings and fixes a lot of other problems buildings use to have. If standards (Eurocode etc.) were different, durability can easily be +100 years or even more for RC buildings with smart details and concrete protected from exposure to negative influences as much as possible. I'm all for traditional and beautiful architecture, not this modernist crap that is being built everywhere, but it needs to be adapted for 21st century safety standards. We should combine following old principles of following forces in our structures with using traditional materials as much as possible, but strategically combining it with materials like RC, steel and timber to build beautiful, long-lasting buildings resistant to earthquakes, high wind loads etc.
Reinforced concrete isn't going away anytime soon due to it being such a great material. The problems cited are nearly all issues resulting from neglect and not issues with the concrete itself. Highway bridges are exposed to extreme weather, nonstop traffic loads, and rock salt dumped on it by the ton, but still last for many decades. If the bridge had a roof and sheathing to keep it dry, was climate controlled, and only had people in high heels and loafers walking on it, I believe it would likely last for centuries.
Great video. The idea of working with nature instead of merely exploiting it, has bearing on all the arts, where modernism in any form has worked against nature: against human nature.
While the video did focus on the detrimental effects of rebar corrosion on concrete it also briefly mentioned some of the degradation processes that are inherent to Portland cement's hydration bonds and porous nature. Much of the Portland cement empire/industry exists as desperate(ly profitable) efforts to overcome its fundamental flaws with admixtures (e.g. water reducing plasticizers) and supplemental materials (e.g. alumina-silicates to take transform excess alkali from being detrimental to advantageous). Make no mistake, the problems (and thus short-term profitability and long-term planned obsolescence) of Portland cement result from its calcium based chemistry. It will never be a sustainable building material and every effort should have been made to develop far superior alternatives like alkali-activated alumina-silicates, introduced by the Romans and rediscovered back in the 1950s by the Russians and used for years for things like bomb-resistant bunkers by the US military. Unfortunately, attempting to maximize private profit/power guarantees that solutions to problems which minimize complete life-cycle costs will be systematically and resoundingly opposed, obfuscated and otherwise buried until the real costs of uncontrolled capitalism become catastrophic (e.g. the currently changing climate).
What about hempcrete replacing concrete? What would be the drawbacks there, other than ending the industry that profits the few while damaging the earth? Growing the plant also sequesters CO2.
10:13 60% is used in China every year. Because every 40 years they tear down the old bridge.And build a bridge 3x bigger.Increase gdp and create jobs for many people. #Planned obsolescence
What about doing something to improve the steel beams used in reinforced concrete to make them anti-rust or free from rusting? Then there would'nt be expanding rusting steel beams that becomes more prone to breaking that exert forces from within to weaken the reinforced concrete.
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Can't we make rebar out of plastic? Especially recycled plastic. It would solve two problems. It would not be as strong, but if made into tensioned nets it would have the same effect. I think it should be tested.
Using cross-laminated timber is a terrible suggestion and should've included (synthetic) basalt as reinforcement material replacing steel.
@@Metal0sopher
Making anything out of reinforced concrete
is an "art form" in my opinion.
It requires, first up, a lot of consultation with the client about his budget,
and a designer, architect/ engineer, and a builder with experience, and knowledge of how much the finished project will cost.
then, all can consider the "alternative materials" and alternative shape of the structure.
If the client is concerned about whether "Recycled materials" are being used, I tell them that a lot of rebar is made from re cycled rail way materials like axels and trunnions.
and also that to my knowledge, all steel is made from about 50% recycled steel.
Steel and concrete are good bedfellows, because they have the same coefficient of expansion and contraction.
it's not a planet
I don't like the 'sustainable' movement since at its core, its full of people who want to justify wiping out large segments of the population. Its essentially a bourgeois movement that seeks to destroy anyone who's not part of the middle and upper-middle class bourgeoisie. This kind of ideology got out of hand in the past but, unlike back then, our modern technology would make the oppression far more effective.
The more I learn about building codes, zoning, and planning in the 20th and 21st Centuries, the less I respect the academic and professional discipline of "Professional Urban Planning". Urban planners have given us everything from urban sprawl to hideous and unsustainable buildings -- and then they have blamed their failures on the petroleum industry or builders or whomever. On the East Coast of the United States, storm water runoff and resultant flooding is a huge problem in the oldest cities. Yet those same cities and adjacent suburbs continue to allow -- and even require -- massive amounts of impermeable paving and building that merely increases the runoff exponentially. I am exasperated with planning/zoning departments and their degreed/certified "urban planners". They are the problem, not the solution.
Humanity would be better off without formal urban planning and architecture. The (human) cost of the occasional shoddy building is far lower than the cost of systemic failure.
The profession developed mostly in response to those same problems. In the absence of planners, people would be paving even more in the suburbs because it's where the demand is. The biggest failing of planners IMO is catering to commuters with their road decisions. It was a rearguard action that was never going to pay off.
@@josephfisher426 Response to those problems??? They gave the U.S. its worst problems. Urban planners devised the modern concept of dividing society into "residential, commercial, industrial". They bequeathed us a loathing of mixed use, and many (perhaps, MOST) municipalities in the United States STILL abhor mixed use in their zoning and planning. In suburbs from Washington, D.C. to Orange County, California, people have to get into their automobiles and drive miles to buy a litre of milk or a loaf of bread, or to buy a scone and a cup of coffee; that drive might be five minutes or it might be 45 minutes. It is no wonder that traffic is constantly terrible in Costa Mesa, Marietta, and Fairfax County. The demise of the neighborhood store or cafe was not merely a pity, it was an environmental catastrophe -- and still is. Only now are a few planning and zoning departments beginning to acknowledge it. But, in the mean time, planners and local governments have trained the populace to believe that the presence of any commercial entity in a residential zone is the end of property values there. Local residents will come shrieking with a whole host of "problems" (almost all of them perfectly solvable) at the first breath of anything commercial in their neighborhoods. It will be decades before any sort of mixed use is advocated as an antidote to the choking traffic of America's suburbs. American's have been socialised to believe in the segregation of "residential, commercial, industrial" -- a 1950's concept that was never even good in theory, and was a disaster in practice. Thank you, municipal planners. You sold us on the idea of suburbs, so now what?
@@billyungen Mixed-use zoning has been a fad in planning circles since the mid 80s, which was itself only about a decade after there was any real planning. Before that most development restriction outside of cities, which did necessary things like banning the keeping of pigs, came from covenants. Covenants aren't really enforceable now, but when land was recently enough subdivided that original purchasers were still a large proportion of the owners, they were assumed to be enforceable.
That mixed-use zoning that was a fad has mostly not worked. It was inspired by older urban areas and it would be nice if it worked. But it's less efficient for business, in an environment with cheap energy costs, to operate in multiple locations as opposed to centralized ones that people drive to. Business is what ultimately chose the current arrangement.
@@josephfisher426 Mixed use "zoning" may be recent. "Zoning" is the operative word. But mixed use is thousands of years old. It has been around for thousands of years because it has great utility. Businesses and citizens today do what government planners allow them to do where government planners allow them to do it. They do not "choose" the current arrangement. Your post is poppycock. If businesses or citizens could chose where they do things, then we really WOULD NOT NEED planners.
We live in consumeristic societies, nothing is built for the long term, not computers, clothes, not even buildings. Sad.
planned obsolescence
Imagine the buildings in Babylonian civilizations...
How long should a computer last? Would you be happy with a computer with the capabilities that were available in most computers 15 or 20 years ago? How about your phone? Same question. The products around us are as durable as we demand, given all the other factors that go into a purchasing decision.
Everything is made for money, not to be used.
@@Monaleenian You would only be dissatisfied, because you have experienced the newer machines. In reality, how much better off are we, really? A 480p video on DVD without all the compression looks better than a 1080p streamed video, because the compression that is used to save bandwidth. Games, especially "AAA" ones, spend all the money on polygons and textures and not on actually being polished and fun. How much more productive are they?
I don't build a new computer every 5 years because I want new stuff, I do it because the requirements for everything have bloated. For phones, it is even worse; it only lasts as long as the battery, which is generally no longer replaceable. The apps don't need better resources, and if I want a good camera, I'm going to get something waterproof and protected, not use my phone.
Great video. As a German, a specific project in my country comes to mind that fits this just perfectly:
The city of Stuttgart decided to put their big train station below ground, and so they are currently building a new underground train hall with huge, wide reinforced concrete structures. Just constructing this is taking 15 years, and guess what? The planned lifespan of this structure is... 80 years. What happens then? Nobody knows. Problems for future generations.
Incredible right? How public funds are squandered on buildings that might need to be torn down after one generation
Many a trillion dollars has been spent in recent decades on High Speed rail tracks that are built atop viaducts constructed of reinforced, epoxy bonded, post tensioned, peer cast, unique concrete segments, that are hopefully good for 40-60 years. That unlike 19th century viaducts can't be repaired with a few bricks and sacks of cement, over a few weekends, in half a century. The stations are but the tip of an iceberg.
@@the_aesthetic_city You failed to cover the ways that re bar can be protected to give a 200 year lifespan. Epoxy Coated re bar will likely last 100 years. Hot Dipped Galvanized re bar will last 200 years...
So if premium concrete is used, with galvanized re bar, a 200 year lifespan is practical. Brick buildings don't last that long, unless they are designed to keep the brick about freezing [no insulation] and the building's mortar is repaired every decade. This is why the smaller buildings in the UK have lasted centuries, because essentially every wall has been rebuilt every century or so...
@@davidhollenshead4892indeed. Galvanized rebar and a good water proof concrete together with a adequate sealing of the building… and it will last 200+ years.
There are plenty of ways how to keep a concrete building stable. It starts from rebar protection, sacrificial anodes, electricity.. to carbon fibre reinforcements. In the tunnels most of the concrete is today shotcrete reinforced by Polypropylen fibres. A former employer of mine SIKA has an awful lot of solutions. I would not worry too much.
The main challenge you are facing is the green ideology that aims for a poor feudalistic society. Such a society does not need roads or large railway stations. In a green society it becomes abundant.
By the way the green rulers of Germany destroy the electricity generation (destroying modern coal plants, envroenmental friendly nukes and replace them by dirty useless solar panels). Trains need electricity to run.
It's amazing to me how mid-20th Century humanity collectively made all the wrong decisions possible. We traded sustainability, beauty, and urbanism that was once working wonders for everyone for greed, ugliness, and segregation. Even when the economic bubble is bursting and the planet is being rapidly destroyed for short-term profit, we still continue to destroy ourselves in name of greed and hatred for our fellow humans. It's sickening.
Happily there is an alternative - but it will be a battle to build better. We can only spread information, vote with our wallets, our feet and of course vote politically. But there is a lot we can do individually to spread the message!
They were busy making easily scalable designs, with low demand on skills. Democractic governments rarely support any long term expensive solutions fearing backlash from industry (less profit) and people (expensive goods). We are also resposible for it. for example, Building norms are designed for 50 years as most people do not want to live in older houses, prefering new houses meant to accomodate latest tech.
that`s post modernism for yay
Segregation? What? I think you've got it backwards.
@@the_aesthetic_city "vote with our wallets" -
you will buy what they will tell you (deliver to "market").
The real face of anti-Traditional architrcture: ugly, souless, short living, unefficient and enemy of the enviroment. Thank you for you videos, great as always
Not sure if you noticed, but the proposed solutions were not entirely traditional either. Plenty of traditional architecture burned down, fell over, or otherwise was destroyed under it's own incompetency in far shorter than 50 years.
@@gearandalthefirst7027 There's no match between traditional and modern. Where traditional was meant to endure it lasted centuries, where it wasn't meant to endure it was at least funcional and ecofriendly (like a wooden cabin house). The solution "not entirely traditional" still had to take the already existant knowledge as reference, while Modernism trashed it like it was just centuries of superstitions. Modernism was greatly moved by the hate for the old, rather than the improvement of things, thats the problem
We used to build buildings that could last 1000 years but many of them were ripped down after only being used for 40 or 50 years. An example of that would be Penn Station in New York. It was designed to last 1000 years but only stood for 53 years and was ripped down in 1963. Thousands of similar long lasting buildings met a similar fate. Modernism arose from the idea form followed function. It is wasteful to put a ton of resources into a building that will only be used for 50 years. If a building is only going to be used for 50 years then why design it to last a thousand?
Most buildings are built to whatever standard the owner can afford, the traditional buildings that last a thousand years are monuments that people have invested in to maintain. No ancient structures would exist if not for engineers and preservationists.
USA urban renewal of 69s did a lot of damage to cities especially on East coast many iconic buildings entire neighborhoods were razed. Salem MA downtown was devastated by soulless concrete replacements.
Fiberglass rebar or basalt fiber rebar is the answer to issues with steel reinforcement. It has many properties that are actually superior to steel and it will effectively last forever. Roman concrete had ash and clumps of unmixed lime that kept the concrete itself from eventually cracking and breaking down. Concrete is best used for foundations and slab floors where, if properly insulated, drained, and not on poor soil, it experiences only compression forces and is uniformly supported by the earth.
I work for a company that produces rebar out of duroplastics. These glass fibre rods are used in Bridges instead of steel rebar. It is resistant to corrosion, so the bridges won't need to be rebuilt every few years
Is this in any way similar to the fiberglass rebar you can buy at a home improvement center?
@buddyrevell511 it is quite similar, yes.
But the resin and the winding of the rebar might be a little different. Mostly because every company uses a little bit of a different approach to make their product unique.
The company I work for specifically designed the product to the specifications and audits of bridges and other large infrastructure
@@mattesr.8680 I tried googling but couldn't find companies that make it; I only found scientific articles and such. Can you name companies?
Sounds like a very smart product! My bodycorp is managing spalling on a 1971-built poured reinforced with post-stress compression via internal cables. In about 2% by area, some 15cm in from the surface of exposed ledges, our rebar rusted. We are in Wellington NZ - windy and salty. It's usual maintenance around these parts; you'd need to build to ocean-going specs for slower degradation. Better concrete now than 50 yrs ago.
That sounds great, but I question it because of expansion. The reason why concrete and rebar work so well together (other than the flaws clearly laid out in this video) is that they expand and shrink at the exact same rate. How does your company deal with that? I'm genuinely curious
Modern architecture has been one of the greatest devil's bargains in history. Thanks for helping us to think about this. And you retain, not so much a sense of optimism but, resolve, that we must deal with this. I gave a lecture on texture that you might find interesting. Thanks. Let's find the ways out of this.
The fact that modern building codes disallow the use of unreinforced concrete is really something
Edit: It seems I misremembered the codes, structural masonry is outright disallowed. Unreinforced concrete is restricted in its use but is still allowed in certain circumstances. I feel my point still stands, the building codes as they currently exist should be rewritten to embrace these types of construction. They are more sustainable than reinforced concrete and glass curtain wall facades.
Many codes are designed in favor of the construction industry
I never understood why foundations, especially low rise home foundations, have to sue reinforced concrete. I always thought that was weird.
One of the problems is that all the regulations that govern the construction industry are passed into law by politicians who know nothing about construction. So they get experts to draft all the legislation for them. To gain expertise, such people need to have worked in the industry. Thusly we get biased rules which assume that the methods in use are the only ones possible. It is also useful for the industry to avoid change because that has a huge cost, not only in innovating designs but in retraining workers and changing supply chains.
This is actually not completely true, within eurocode 2 which is used in Europe to design concrete structures there is a chapter about unreinforced concrete. However there are quite strict limitations to these as unreinforced concrete fails in a brittle fashion, giving occupants no time to get out of a building when it starts falling apart.
@@2mains234 the real problem is not the type of regulation, but rather the OBSESSION that everything MUST have rules governing it enforced by the government. this is the real evil.
For architects and builders, start with: "Building with Lime: A practical introduction" or "Hot Mixed Lime and Traditional Mortars".
Until we start running out of lime like we are doing to the beaches?
@@MisterHeroman 1st of all: Lime-based concrete, hydraulic or non-hydraulic, is not a substitute for common concrete (PCC) used in construction today, which utilizes Portland cement as a binder. Lime constitutes 60-67% of raw materials consumed in Portland cement production. PCC is the second most consumed substance (right after water) in the world right now, as we speak.
2nd: Quartz sand is mostly used for decorative lime plaster, which is the smallest part of lime-based construction materials and should be preferably coarse - so neither river, nor beach sand are optimal.
3rd: Reinforced PCC should be, hopefully, replaced mostly by engineered wood in high-rise and infrastructure projects.
4th: You should do basic research on cob, adobe, lime stabilized earth etc. - you'll love it❤
@@vadimskyWould engineered wood beams really be strong enough for use in high rises??
@@daxisperry7644 There are some videos that show examples of high rises that are being built with that type of wood
@@vadimsky I have done quite a lot of that research.
I am studying civil engineering right now, and it is crazy how much of the lectures revolve around the use of reinforced concrete. I believe one of the main reasons for this is the fact that most people that want to construct buildings are wealthy people, and exactly those people do not think in a sustainable way, since this will not net them the most money. And i worry that since this is the case we will not really see huge changes in the near future. Tho brickwork is gaining a lot more popularity again especially for private contractors, and building with it makes it "only" 6-7% more expensive.
Yes there are many ways to design with other materials- they cost more, just like preventing rusting of the rebar, but we need to make a choice if we really want to be sustainable. Otherwise, we are just greenwashing or virtue signaling
@@the_aesthetic_city This is very true, i really hope for more movement in that direction. And in this regard i deeply appreciate what you are doing.
Have you discovered "passivhaus" standards yet? You should take a look at designing buildings that need almost zero heating or cooling.
@@disposabull yes ! though not fully into detail yet, but it is being talked about since they do try to be sustainable in many ways.
If reinforced concrete is used for the floors and the roof is properly maintained... Why would it last only 50 years or even just 100 years?
I don't like concrete as a finished surface of buildings either. But the dufference is very important and not adressed.
There's a lot of construction industries here in France which know how to built without concrete, since we still have building like that almost everywhere...
Building methods aren't lost and the problem is not that they don't know but they don't want to change
people aren't ready too to pay for a good and long time construction since it's much more expensive ..
In France and Italy, many traditional forms of craftsmanship are still preserved but in America; these types of old crafts have been lost to history.
Um, don't leave large spaces in between your sentences - it's annoying.
@marblox9300 Well, it's sounds like a YOU problem, being annoyed at the way someone paragraphs their comments, lol. I find that funny as fuck. Especially coming from someone that uses a dash instead of a comma. Haha!
(Double spaced paragraphs just for your enjoyment)
Your comment just makes you look like a Richard Head.
@@ShawnNac Not a problem. Idiot. LOL.
"Building methods aren't lost and the problem is not that they don't know but they don't want to change
people aren't ready too to pay for a good and long time construction since it's much more expensive .."
I'm French and I disagree with that statement. A good and long time construction is not more expensive. In fact, it's the opposite. That's why buliding with clay, straw and so on (for example, using technics like they do with Kerterre) is not legal. Precisely because it's super easy to do and super cheap. But building is an industry and a market. And that means lobbies... Someone who buy a land and build a house in clay (for example) will not have the permit, even if everything is ok with the septic aspect and so on. Why ? Precisely because doing that, you don't pay those markets.
I can't believe it isn't common sense anymore to build buildings that won't degrade in a century. It's ridiculous, because in many European cities, the same people who build with this mindset are surrounded by buildings one and a half, two, sometimes even THREE centuries old. Thanks for the video
Absolutely! We need to start thinking far more long term
please take note that reinforced concrete hasn't been in the industry for that long. The estimate 50 year life span has considered multiple safety factors. Technically, they can even live more than a century. Those non reinforced concrete you have mentioned will easily collapse after an earthquake and kill people instantly. Not to mention the limitations these kind of structure have (you'd need bigger walls, bigger columns, that reduces your indoor space, goodluck finding a big lot for that)
We have cathedrals, old scyscrapers, that still stand after 5 centuries
@@user-yd4tm3gl8s and how many of these cathedrals have also collapsed if they are not maintained or further reinforced?
Plenty of buildings outlive their usefulness. Areas get developed and redeveloped to accommodate the needs of the residents in the area.
There is also a Chinese concrete where you don't have to wait 50 to 100 years, they can collapse halfway through the building progress.
Don’t be foolish. Every country has construction problems, the US has her share.
The problem is not in the concrete, it is some people cut down the use of concrete.
Yes, it contains tofu
@@JayTse-x7lThere has been an epidemia of such incidents called tofu dreg in China even in prestige projects. Well, in communist China.
Cutting corners and lack of health and safety is far worse over there. They don’t call them Tofu buildings for nothing.
There is an advantage in short lived buildings. Since there is no way to adapt a building to every technological innovation that comes by (think piped water and sewer, air conditioning etc), it's actually good that the building is cheap enough to build so that it can be torn down and another, more modern building is allowed to be built using the same piece of land.
That works for offices and homes. Not so much for things like bridges and dams.
Or we could plan our houses to have room for future pipes and cables and ducts, and build homes that will last through the centuries.
@@tealkerberus748 It would not be too difficult to put these things behind access panels instead of burying them behind drywall. I'm surprised insurance companies don't insist on it. Problems with plumbing and electrical wires fester unseen inside walls, by the time the damage is noticed it is usually catastrophic; severe water damage, mold problems, electrical fires, etc. Stuff that is typically covered in home insurance and costs the insurance companies.
Urg the trend that is bugging me right now is in my home city we have a bunch of really nice red brick-clad buildings, and for whatever reason everyone feels the need to paint all the wood, brick, insides, furniture everything blank white. I'm so sick of white, it's the concrete color of the 21st century. White is nice, too much of it though is just painful. No color, we can't have color anymore, everything must be white. Then in front of these houses, they take the lawns and make them artificial turf because covering our organic lawns... in plastic is a great way to save the planet, don't have real plants just imitate them with plastic.
Oooof a lot of people in my neighborhood are doing that to their brick houses. Which is so weird to me because the brick never looked old.
@@JakeHGuy Same... I know right, what's wrong with brick?
Yeah what a gross trend. It's as though people want everything to be a homogenic giant mental institution.
Lawns leaves in mass are able to produce oxygen which is very important in cities. Help absorb water and reduce erosion and flooding. They also have a cooling effect. The leaves breathe in CO2 and exhale O2. The carbon is in the roots. Mixed with trees plants and shrubs is very effective mitigation for the above reasons. They also help with noise pollution to a degree. Why you would want use plastic lawn is beyond me.
Due to the processes and life span of concrete the cost isn’t really sustainable or effective. Resources are finite. While it may cost more for other construction in long run for the life of the building is cheaper and more likely to retain real estate values. These buildings even as shells from lack on maintenance especially on wooden and glass fixtures still go for millions in city areas to be rebuilt and redesigned into more modern architectural designs using different mediums. Personally I find it offensive to disrespect the architecture from the period the building was constructed in. There is a beauty in the old architectural designs that modernism and brutalism totally disregards.
It really is an annoying sterilization. Starting to drive me nuts too.
It’s remarkable that buildings are typically planned with a lifespan of just 50 years. I hold the view that this approach is deliberately encouraged and endorsed by the influential figures of our world. Instead of seeking approval, we should forge ahead toward more sustainable practices without waiting for anyone’s sanction.
We have become a "throwaway society". Our municipal dumps are bursting full. Home appliances are not repaired - they're replaced. Automotive repairs are often replacement of entire modules. An expensive computer is discarded when one tiny soldered element fails. And so many buildings are torn down because they are "obsolete".
Another building material that is thrown away are tiles! Buy an old apartment and the buyer will surely tear the ‘old tile’ down and install ‘ modern’ design tiles…..however good condition the old tiles maybe….
,
& Our wood framed house is 100 years old. Owned it for 36 years!
@@Fetherko I lived for 30 years in a wood-framed house built in 1771. Now I've lived in my custom-built wood-framed retirement home for 23 years.
@bobrogers99 but why is this the case? What are the underlying economic and cultural reasons that led to this?
Also look into reinforcing concrete with graphene. The results are quite dramatic - stronger concrete that can reduce the amount needed by 2/3c IIRC.
Another greatly underestimated material is just metal itself. There are plenty of metal alloys that are corrosion resistant so they last a very long time, and can be very beautiful as well, just look at historic cast iron facades. You'd keep the advantage of affordability too, since you can just press and stamp a large variety of beautiful shapes into metal plates, so there is no need for expensive artisans. Not to mention you don't need much of it since it's so strong, so less material has to be used and mined, and it's 100% recyclable as well so once it's produced it stays in circulation, plus you can process it with renewable energy. With proper interior insulation you don't have to worry about heat and sound either.
I don't know...
The Lustron didn't age well, i cant imagine in bigger buildings.
There have been studies into what it would take to replace our annual output of concrete buildings with steel. Likewise what it would take to replace them with timber. It was all wildly unfeasible.
@@tealkerberus748was thinking this. We would need massive deposits of iron ore, the type of supply we'd only get by mining Mars, which would be a conservation tragedy
The reason the pantheon still exists is that every generation since decided that this one building was worth preserving. The plain concrete developed large cracks had to be found and repaired to prevent collapse. It should be obvious that every building cannot receive such treatment.
I come from Singapore. It is a tropical costal city where almost our entire city is built of reinforced concrete.
We have many buildings that are over 50 years old and most of our buildings are made of reinforced concrete.
Concrete that is exposed to the elements is covered in plaster for vertical surfaces, to increase water resistance.
For horizontal surfaces, we use waterproofing membranes below the plaster and slope the surfaces to drain and replace the waterproofing every 20 or so years.
Our buildings are frequently inspected by structural engineers and many of the 50+ years old RC buildings are still standing.
I thus suggest that you have exaggerated the problems posed by steel in reinforced concrete because there are solutions to prevent water ingress from causing rusting of rebars.
Save for this one point, I agree with the rest of your points.
I must admit though that we can’t see what’s happening below the soil to the foundations where RC is used extensively for pile caps, piles in some cases, contiguous bore pile walls, etc.
However, if the foundations suffered from degradation of rebars from water ingress and rusting, we should expect to get cracking and gradual failure of the foundations together with a consequent subsidence and tilting of the buildings. This we have not seen.
YES! THANK YOU this is such bullshit and so easily solvable too:
"The main cables of the Golden Gate Bridge can't be replaced, they have to be periodically painted and cared for exterior paint is really what protects the 80,000 miles of wire inside the cables from corroding," Currie said.
Of course it's exaggerated...
Singapore never freezes. Where I live (northeast US) there can be hundreds of freeze/thaw cycles a year during winter months. The “native” architecture is traditionally wood with clapboard siding, steeply pitched roofs, and deep foundations that reach below the frost line. The wood requires maintenance but is pretty much immune to freezing and thawing damage.
@@ClockworksOfGL that’s an extra dimension of difficulty. How do you build and maintain RC buildings and structures such as bridges in these climates?
His point still stands, because many places don't effectively maintain their buildings and infrastructure. Just because you are an exception to a rule doesn't disprove the rule.
You also don’t have freeze+thaw cycles to speed up the problem
You can start watching from 5:40, you're welcome
"and so castles made of sand fall in the sea, eventually" 🎸🎶
Right on, rock on LaMach ! 👍👍🎼🎼
I like your attitude 😎👌
More industry needs more people. Both needs more buildings. People need livable spaces. They need it as cheap as possible. These are the basic problems, modernists tried to solve. Arches and vaults need hight, stone and brick walls are thick. They mean less useable space in the building. Slabs are more cost effective made of steel, later of reinforced concrete, also walls. Ornament costs a lot, but is not "useful". (Beautiful, but who cares?) Modernists tried to make philosophy for the new material: "The beauty is the aestethic of structure". In some cases it is, but generally the investor is not interested, or there is no time to refine the plan, or the architect is not gifted or trained enough to make beautyful plans. Some architests are "artists" who make statues for themselfes...
So that's what led to the overuse of reinforced concrete. Meanwhile the knowledge of making ornaments or vaults has been almost lost during 20th century. To build any form made of concrete is easy and builders have its knowledge. Making vaults need more time, makes more cost. The main drive force here is to build quick and cheap.
you are making an honest argument, but wasting your time here - the audience is a bunch of traditionalist snobs, who only care for their narrow privileged "visions".
The end of WW2 brought about all this “quick and cheap” short sighted ideas of reinforced concrete.
So much needed to be rebuilt as fast as possible for little cost, so most countries went the short sighted route that is now having disastrous consequences on us.
@@alexsmith-ob3luwhat else could they do? Let people sleep on the streets? Specially with baby boom. You pretend like they had options specially countries hardest hit by the war.
Yeah, people nowadays seem out of touch with reality. We already have housing problems, ridiculous rent prices, etc, and they suggest we suddenly make construction 5x more expensive per square meter? I mean, I get it, we're apparently doomed if we don't quickly fix the environment, but come on, be realistic, you know?
To be fair, bridges, dams and large public buildings such as train stations, for example, could indeed be constructed with arches. Build them to last.
However, how do you build a 10 story or 20 story building with arches in a confined space? Good f'ing luck. I guess here the issue is that huge metrópoles shouldn't exist in the first place. Jobs would have to be more distributed in multiple cities so that the population density decreases, requiring less multistory buildings.
Another great episode.
Also Roman concrete was a bit different and it has self repairing properties. Practical engineering channel has a great video about it 🙌🙌🙌
"Roman" no lol. Its tartarian.
The ingredient you're talking about in 'Roman concrete' is quicklime. Concrete has that already. What makes roman concrete repair is the reaction with calcium in quicklime and the saltwater, thus calcifying and filling the gap.
The issue with that is obviously that saltwater rusts rebar very, very quickly.
@@mhx6437 its tartarian. Not roman.
@@meinkek7896 shut up
@@mhx6437 its tartarian.
Partial solution for reinforced concrete: use synthetic basalt instead of steel or iron with or without coating(s).
Does the limestone not get eroded? I studied a limestone landscape and the limestone is susceptible to be eroded by acid rain. Acid rain dissolves limestone because the limestone reacts with the rain to create calcite which is soluble. I only know about Karst landscapes though, is something done with buildings to make them less susceptible to this?
Please search Red Fort of New Delhi and Agra Fort in India. They are standing for 400 years or so.
Retired engineer here.Concrete is the most versatile building material available. From sewers, tunnel liners to high rise buildings and bridges. Lessons learned are being applied to protect rebar from corrosion as one small example.
Also the other main building material to frame a building is steel. That works in some places but not all.
It’s all a matter of cost . Plus Buildings and infrastructure are needed urgently to serve a growing population . What is the quickest most efficient means to meet that need.
As far as architectural beauty, that is partly related to what owners are willing to pay for the features. Plus the time to build.
I agree many modern buildings, esp. residential complexes are rather ugly.
But I don’t think the reason is the use of concrete .
Anyways, concrete isn’t going anywhere. It’s here to stay. The engineering challenges are to make it last longer. Corrosion protection (coatings) and catholic protection are a couple of ways to mitigate rebar corrosion and extend service life of the structure.
Very well said! There is nothing worse than soul crushing concrete and your solutions sound pretty viable. Also, in Italy, even most of the "newer" buildings today are still built with arches, you can find them in the neighbourhoods built in the 1950s to 1980s in cities like Venice, Milan and so on.
Now I wonder if the glass industry is causing similar problems for the environment, especially coupled with concrete...
Architect here. About carbon capture technology(CCT) - the NORM here in Norway, after grilling the concrete industry-representatives(Betonmast): they capture the CO2 with a filter at the factory, and put the pressurized co2 in tanks. These tanks are then shipped by truck to the coast, where they they are loaded onto ships, which are then.... dug into the seabed. Literally putting their problems in the silt.
So much energy and fuel being spent on transportation, pressurizing and even the capture, this makes absolutely no sense
@@mattllaves They've just figured out how to play the Co2 regulations so it looks good on the spreadsheet. There's alot of awareness and regulations being discussed to avoid greenwashing like that fortunately. Notably, there's an anti-greenwashing pledge that most architecture and engineering companies are part of, where they use other measures in addition to Co2 to measure sustainability. In 2021 we(the government) also implemented a 50-year rule for all new buildings, meaning they must last 50 years without serious maintenance.
Most architects and engineers worth their salt are also aware that designing buildings that can be adapted to future changes in use and needs, be easily maintained, not to mention simply being beautiful will make any building last much longer.
I wonder if they really do that, or they fake it?
Here's something that very few folks are talking about,;
All plants and trees need Sea oh two to live.
And very few folks know about what a miniscule percentage of our atmosphere is c 0 2.
Trees and plants absolutely devour untolds of see oh too.
And we spend a fortune dissolving it, (under pressure), into our drinks ,
no one likes flat beer or soft drinks.
Would any University educated folks like to help me write and publish a book called
"A hundred and one uses for si oh two".
Which material is used to fabricate these storage tanks?
Hello Aesthetic City, what are your thoughts on the return of murals to public spaces (particularly indoor public spaces) in newer classically-designed architecture? Murals, bringing a painted form of life, emotion, and beauty to public and common spaces, were quite common in older, classically and traditionally-designed buildings, but don’t seem to be too common in newer classical/traditional buildings nowadays.
Entirely depends what the mural is. If it's some Cleon Peterson piece I'm gonna have to pass on that
A mural to the classical standard is one thing. Unfortunately, the murals I have seen have been childish, dehumanizing monstrosities.
Earthquake resistance is a consideration. Unreinforced masonry structures are very vulnerable.
So use nature's ultimate, infinitely renewable engineering material: wood. There are plenty of 500 year old wooden structures still standing because repairs are easy and it's really damn strong. We don't need 50-storey high-rise apartments if office work isn't concentrating all the jobs in 50-storey office buildings
Ok no, first of all. If this is a problem you think nobody is talking about, it's because you're not related to the engineering and construction world. And if you are not indeed related to that field, I understand the existence of the video, because it's pretty uninformed.
For all the problems you described, there are a lot of ways to avoid/solve them, to the point that it's 100% the builders to blame. For freezing conditions you have additives, for coastal buildings you have noncorrosive steel, additives that close the pores of concrete, special paintings. For alcali the only solution i know of is to choose the right materials beforehand, it's something that's not common at all in my area. All pathologies have been studied, documented, analyzed. There are a lot of publications of a lot of laboratories and professionals that investigate how to solve them. None of them is a "dark true" or "something not talked about".
It is extremely important that professionals are well trained in the material. That's the main reason of all the pathologies associated with reinforced concrete. Just don't blame the material for the errors of the builders. If contractors in your area build poorly, denounce them, not their field.
This channel just shits on everything that is not "classical"... Of course they have no idea what they are talking about.
@@uisgeuisce
Re. the two previous comments;
Non tradesmen are welcome to talk all they like about how producing cement produces more sea oh too than aviation.
I don't believe THAT for a moment.
Repair folks call the problem of rebar rusting "Concrete Cancer".
If rebar is covered with enough concrete, our atmosphere cant harm it,
also there is just so many way to extend the life of structures made of rc Concrete,
i'd take a month to explain it.
I thing you two guys sound like you have some "real world experience", in the building and construction industry.
Time is valuable, so I'm gunna leave the discussion to the university educated folks to have a text book talkfest.
@@benjigray8690 no idea why you are replying to me and what's your point. I'm an architect and this channel is not sincere in his analysis to the point of making shit up. Don't have time either to lecture people on the internet.
The fact remains. All modern steel-reinforced bridges have a maximum lifespan of 50 years. That just sucks. Might as well not build them at all, at that failure rate. Yes, we know it's a flawed product, but we will go ahead and build it anyway.
@@shanemedlin9400 50 to 100 years at least if done and maintained properly. Well next time it happens you get to use a bridge or highway please don't. Or even better! Come up with an alternative to it you may as well become a billionaire!
I love this channel
0:11 LOL BS...the concrete should not be destroyed and replaced..when you say renovation and demolition, it happens when you want to build a more profitable building on the respective land. In many cases, the blocks are located in areas with extraordinarily expensive land, which is why they are being torn down and the respective concrete is recycled into other building aggregates...I live in Eastern Europe and I own several apartments in these concrete blocks and I even invested in brand NEW apartments recently built of brick with a concrete frame that are inferior to the old 100% concrete buildings. Not even on the seashore, where salt is a major factor of damage, does it cause problems for the blocks to be demolished. This video refers to the blocks made by Americans with very weak cement in no case to the old European blocks that have been standing for 100 years without a problem and that will stand for many generations to come
I do really hope you're right on that one. First because it would be so dramatic to imagine that all the concrete buildings are at major risk to just fall off with all the people who could die in this process... Second - very more minor aspect - concrete house are the only affordable houses in my budget in France (all the concrete houses from the 60's and 70's). So if I buy one, I hope I can keep it for at least 50 years more...
I have been anti-rebar from the beginning, so nice to hear someone else talk about this.
The building material of the future will be melted rock - by _sintering_ stone into a basalt like agglomerate we can create almost indestructible bricks in any shape imaginable. By assembling these bricks on site acording to computer aided design, you can erect extremely longlasting and absolutely beautiful structures by fitting these tgogether as Lego blocks - which allows deassembly and recycling blocks in the future. Variants of this asembly of hyperdurable rock components are 3D printing sintering desert sand thrugh a freznel lens - as wonderfully evidenced my Marcus Kayser.
Does this technology already exist?
I believe this is the plan with constructing habitats on the Moon, and eventually Mars. By cooking the regolith we will be able to fly there with less materials, making it more cost efficient, among other benefits.
Sounds like incredible amounts of energy needed to do this.
but is it relatively cheap and easily scalable? cuz if not, it's unlikely to catch on large-scale
Why waste the energy when earth already made rocks and it is comparatively much less energy to just mortar them together. This seems foolish.
Civil engineer here! Great video! Corrosion is a huge problem for us right now. People have not realized that when they were building with concrete in the 70s or the 80s, they where building for approximately a 40 year lifespan. Now everyone is in denial they either need to either tear it down or spent a fortune to retrofit it.
Great video. I already dislike the look of concrete buildings, but I had no idea they were so impractical as well.
Love the visual presentation of your videos as well, and I'm glad to see you're comitting to your unique illustrated visual style. They're not just fun and stylised, but their simplicity also helps make the more complex explanations (such as how the rebars can get rusty) easier to comprehend.
Thank you! Will double down on our unique look :)
rebar in concrete used in buildings isn't really susceptible to corrosion anymore than steel beams are. rebar corrosion is only really a issue for concrete exposed to weather.
And lime facade protects the concrete exposed to elements.
Cement rot is not inevitable.
It's notable that there are non-corroding rebar options. Fibreglass rebar is already on the market, and other options probably exist.
Epoxy coated rebar and stainless steel rebar is already common
interested in some of the ash self healing concrete as well.
curious what lifespan pf fiberglass is~ how rigid is it?
@@Khanfuzed1 For many applications fiber reinforced concrete is similar to steel reinforced concrete. However, many of the fiber approaches give me strong asbestos vibes.
Yes, true - but the cost is often prohibitive. Still, it is one of the solutions. Maybe that will be the way of the future
@@Mooooov0815 To be fair, if even asbestos was embedded deeply in concrete (and never exposed), it would be fine. It's when it powderizes and gets into the air that the mesothelioma can-can starts.
The rust thing is a non-issue in most buildings because they use rebar that's already rusted which is then covered in concrete. The problem with rust is that it is very fragile, but otherwise it's a very good protective layer. Rust is a non issue once covered in concrete because concrete protects it thus counteracting rust's fragility
Noting that pink rebar (made of fiberglass) is stronger, lighter, cheaper, won’t corrode and it’s a fun color. Sodium bicarbonate can be added to dry mix to reduce the c02 emissions of concrete as it cures, and in the cement manufacturing process, the heat used to make the portlandite can be reclaimed to generate electricity. Same with the emissions. It just requires government legislation to do so.
Concrete doesn't release carbon dioxide as it cures. It absorbs it. All the carbon dioxide that was baked out in the process of making portland cement will eventually be absorbed by the concrete in the process of curing.
Its really depressing how most new buildings look disgusting and detached from history and culture. Its really hard to not vandalize them.
Modernist buildings so ugly they can be modern art masterpieces, to quote a famous drill sergeant.
Excellent video! I just discovered this channel. I've been involved in sustainable and circular construction for many years. In 2011 I became project manager of the Dutch Concrete Green Deal. This was an industry initative to find out how we could make the concrete sector more sustainable and set up a deal to make it happen. In 2016 the deal (with the Dutch Government) was formalized ("Beton Akkoord"). Unfortunately I'm not so happy with the speed at which the changes are happening, but the sector has definitely changed in my country, using a lot of recent and less recent innovations to lower their carbon emissions (which were already the lowest in the world per m3 of concrete when we started out), and increase the use of secondary materials. I can mention several options which have not been mentioned in the video, but there's 2 very promising ones to add in the comments:
1. Reinforcing concrete with basalt rebars. This gets rid of the problem of rust limiting the lifespan of concrete to 50 years or so. There are still one or two challenges to overcome for this fantastic material, but it holds great promise. There are other options as well (like fibreglass) but they also have their challenges.
2. Closed loop recycling using the 'smart crusher and similar technology. Current standard recycling technology is able to recycle part of the concrete as an aggregate alternative. This works fine for less demanding types of concrete (like pavement blocks and such), but is limited when it comes to concrete for flooring or infrastructure. More important is that this recycling technology is not very good at producing a substitute for sand in concrete. The innovative 'Smart crusher' is capable of producing very clean gravel and sand products that are comparable to the original material and can be used for high quality concrete. The remaining cement/ fines fraction is more difficult to recycle, but Heidelberg is working on using this reactive material after further grinding as an additive to cement. Currently the demand for concrete is quite a lot larger than the amounts of concrete that are 'harvested' from demolition, so recycling can only lower the demand for primary resources, in the Netherlands a maximum of about 25 - 30%. But it can certainly help, in particular the demand for sand.
What I very much like about the video is the idea of building for longetivity. Not 50 years but a 1000! This is an important goal for circular construction, both for buildings (and infrastructure by the way) and for construction products. Sometimes a shorter life span is preferable because it is unavoidable that the required functionality is going to change, and built in adaptivity is not possible. Then re-use of construction products and elements are possibly a better option. Instead of a construction with a long lifespan you create construction products with a long life span. I was involved in the design of a circular viaduct which was based on modular blocks that can be reused many times over a projected minimum life span of 200 years.
You also mention the importance of standards (which you call 'norms' - a word which in English has a slightly different meaning, but I'm sure you mean 'standards'). I am currently chairman of a new working group within CEN (the European standardisation institute) that is developing a standard for circular design in construction. This will lead to technical requirements for both constructions and construction products including aspects like lifespan, adaptivity, maintainability, reparability, detachability/ deconstructability, reusability and (closed loop) recyclability. Let me know if you are interested: you can find me on Linked in (Evert Schut). Or - if you are situated in Europe - you can contact your national standardisation institute to join us.
Left out the major drawback in using compression only construction; being limited to low rise buildings, especially in earthquake areas
Earthquakes can happen anywhere. And even low-rise, I wouldn't want to be in an unreinforced masonry building when an earthquake hits!
You can still use steel outside of the concrete or coat it.
@@0MoTheG If the steel isn't embedded in the masonry it's not going to work the same way.
I think we need to completely re-engineer how we do concrete. Purely compressive design with no reinforcing isn't the way, and mild steel reinforcing that rusts within a century isn't the way either. People are using basalt fibre with good effect where it's properly engineered, but it you get it wrong you have a concrete structure that fails without warning - one of the advantages of steel reinforcing is that the concrete can fail and you'll see it crack and sag but the steel holds it together long enough to evacuate the building. Getting that feature with non-rustable internal reinforcing is easier said than done, but that's what we need to do.
@@tealkerberus748 Yes it does not,
but steel can take both loads. To make a floor you can use steel beams and lay fiber enforced slabs ontop.
4:52 just to be used stainless steel for the inforced concrete and the buildings can upstand dor 250 up to 1000s years, depends on the stainless steel properties. 😎
Hope this channel gets the attention it deserves!
if the rebar is at the correct depth in the mix it will last longer i have observed many a repair and the rebar has only been 4 or 5 cm deep
Concrete buildings have a average life span of about 300 to 500 years. (average doesn't say anything beside it is always longer than 300 years)
The concrete is only filling, what keeps the building up right are the metal beams within the concrete.
Even if you take all the concrete away the building will still remain upright from its metal skeleton alone.
There are some products for reinforcement that can be used in the short term during the transition such as epoxy coated rebar or fiberglass rebar, but you are right going back to the old materials would be very beneficial except for very tall buildings where it would not be as practical. Good video.
This video is truly misleading. Non-reinforced concrete buildings indeed demand exponentially more concrete volume compared to their reinforced counterparts. This oversight leads to a ripple effect of increased carbon emissions, heightened sand mining, and escalated carbon emissions from transportation due to the excess materials required. Moreover, the economic and affordability aspects cannot be ignored. Constructing a building to endure for millennia, not just a century, is admirable, but when it necessitates ten times the materials, it raises serious sustainability concerns.
Of course, concrete is a major carbon emission contributor and we should do more research to mitigate its environmental impact. However, opting for non-reinforced concrete, especially using existing common concrete, is not a wise idea.
Consider the hypothetical scenarios: If all reinforced concrete buildings were constructed using non-reinforced concrete, akin to ancient Roman practices as the video suggests, the current atmospheric carbon levels would undoubtedly reach catastrophic levels. Alternatively, envisioning a world where all reinforced concrete buildings were replaced with timber structures highlights the peril of excessive deforestation.
Yes, concrete emits lots of carbon, but concrete is not the enemy. We managed to reduce carbon emissions to these levels and use less resources while facilitating shelter to the people thanks to the concrete. However, carbon capturing in the cement-making process, and alternative less carbon-emitting innovative materials are some actual answers to reducing the impact.
I think 50 years is simply not true there are brutalist buildings in my city made from exposed concrete blocks, that are already over 80 years old, they seem to be still structually sound althought you can see some deterioration. There are many concrete buildings around Europe which are 200+ years old and stand perfectly. Newer buildings that are done with European standards have insulation that further protect the concrete from outside influences, these buildings will definitely last longer than 50 years.. also to finish most buildings aren’t only supported by outside walls, they have massive pillars inside the building which hold the weight and they can’t possibly deteriorate fast because they experience no outside influences.
My issue with concrete is that the building is homogenous and thus construction has to be continuous. If only it was more modular, then you can just replace the elements individually. Thankfully, there is precast concrete where you can just remove only the damaged portion instead of destroying the entire structure. Of course, depending on the structure, mileage can vary.
12:03 Why the would steal the sand of beaches? you mentioned in just 5 second earlier that only river sands can be used for concrete for their rough edges.
reinforced concrete structure can be also long standing, even for thousands of year with proper design and construction, with protection against moisture, that other buildings cannot tolerate either, (wood will rot and develop mold, stone can be also ruinned by frost cycles..etc.). Cement is one of the most useful binding materials we have to house milliards of people..there is not enough stone caves or pyramids to house 8 milliard people..the burning of bricks also need energy..adn there is Ytong, a lime based cement structure..
I live in a 112 year old concrete building. Should I be worried?
The more you know, the sadder you become...
As you said the CO2 from portland cement comes from the CO2 released when burning lime, it's weird to not mention that this CO2 is reabsorbed when it sets (called the lime cycle.)
This was really informative and interesting.
Thank you!
One of the reasons our quality of life is so much greater than that of the Romans is that we have massively reduced the cost of building. And this is undoubtedly because of reinforced concrete.
Enforcing a rule to design buildings to last 1000 years may sound like a good idea on the surface but it would increase the cost of living in general, by a massive amount.
It would also result in many projects not being funded as they would cost so much.
Long term we should be looking at materials such as basalt, no CO2 reaction to worry about! This would require new building regs so not a short term solution. For now I like the idea just using stone and craftsmanship!
Concrete itself should be replaced by something which is better than it, not that we know about any alternative right now. But concrete is highly problematic, it's not that strong either.
Great video! Very interesting subject that we learn about in architecture school but that civil engineers don't care about.
I'm a dual-trained architect and engineer, and this question of a return to geometry in the natural order has been on my mind...
The question is how to introduce these more reasonable construction methods into a capitalist system that relies solely on short-term profit?
We still have a lot of work to do in this direction...
On one hand you are totally right, the massive and often crude use of concrete is a big problem nowadays. But on the other hand you aren't considering the reallity of much of those buildings: Many of them were build when millions of people needed homes. If millions of people search for living spaces it's a much better idea to build an appartment block where thousand people can find shelter than building a dozen single family houses for some dozen people! So it's true that they could have been build in a more sustainable way but two story family houses aren't the solution either.
I'm afraid building to last 1000 years instead of 50 is greatly incompatible with the economic systems we have in place. They depend on deterioration of things to keep money flowing
Build with wood?
Money flows regardless. People don't just save their money because there is one less thing they have to spend it on
There's an over indulged interest in profit at any cost to humans, as opposed to living for a good sustainable life.
It’s actually because democracy has a high time preference.
Hmmm. Are you sure of that? Rome has a massive tourist economy, as do all antique towns with castles throughout Europe.
Every building material with the exception of wood, comes from a whole in the ground. Not using reinforced concrete leads to using more building materials. So it's not that straight forward. Also the CO2 that is emitted by making cement, from the chemical reaction, is absorbed when the concrete sets. So I don't think that's the biggest issue.
Well, living in reinforced concrete structures is not so common in Germany and probably not so common in much of Europe. Individual houses are built from brick (Poroton thermal clay blocks for example) and much of apartment housing for rent up to 4 floors uses such porous bricks as well or lime-sand-brick (Kalksandstein) for the structure and decorative clay bricks for the facade. Outside of earthquake zones, reinforced concrete is rarely used for low-set residential structures. Only high rise apartments and public/commercial buildings use reinforced concrete a lot. Modern basements and floor slabs are usually made from reinforced concrete though. My grandfather's house, with wooden floors, lasted from the 1930's to the 1980's with minimal renovations. Since then many things have been refreshed and new materials have been introduced, but the structure is basically the same. It will certainly last over a hundred years, but probably needs to be thoroughly rehabilitated every 40 to 50 years.
Whether those highly insulated modern residential structures last more than 50 to 75 years is doubtful as well though, due to the complexity of modern building systems which often include foil layers for air proofing and water proofing and polystyrene on the outside of the facade. The wall structure could possibly last more than 100 years, if the modern thin mortar-glue for the insulating Poroton blocks lasts that long., but heating systems, plumbing, electrical systems, roof and wall insulations all expire much faster than reinforced concrete.
Oh, you germans call those white porous bricks "Whyte porous bricks" too? 😂
Having studied civil engineering myself, it's so uncanny that RCC is considered the primary building material for almost every structure and all codes somehow revolve around it. I come from the Himalayas and the primary building technique used here traditionally is stone masonry. However, I find them structurally very weak in lateral loading due to earthworms as this region comes under seismic zon 4 or 5. The codes recommend RCC. Personally, I also feel there's no other way except RCC in this case. All we can do is minimise the use of concrete but can't get away from it completely.
use basalt rebar instead of iron ferro no rust cracking
I am glad that increasingly more US construction is conducted with OSB. This material is a wood material that is arranged into square or rectangular panels and structurally strong, regardless of the direction of the grain of wood that is used to manufacture it. so long as it is kept away from water, it is a very robust material that survives well in terms of earthquakes. This material is also relatively easy to treat to improve fire resistance.
OSB construction is the bane of firefighters because it burns fast and it is toxic and has a short lifespan.
I suspect the above comment is from a bot.
By way of observation amongst the people in my life, both sides of the spectrum, I find most post-modernist artsy-fartsy types are fairly left-leaning and with this video, you are convincing them their less-than-lovely, preferred styles are actually unsustainable. For some people who love their brutalism or the 'cult of the ego' style buildings, this argument to choose alternatives to concrete may cause cognitive dissonance in many, leading to some who might... just might actually have to accept that their beloved 'beauty is in the eye of beholder' monstrosity is hurting the environment and cheap materials that form our cityscapes lead to eventual 'dis'function.
Me, personally I love this argument and whole heartedly would love to see a renewal in beauty in architecture. A revival of beauty is necessary for the sake of humanity's soul. As such, I am convinced even more and have learned a great deal. Dank u wel. As for the above-mentioned types, the questions remains: will facts win over entrenched feelings? These days, I can hope but I never hold my breath.
Welcome to cognitive bias. It's harder to convince someone they are fooled than to fool them...
@@theotherohlourdespadua1131 It's good to have a name for this form of bias. I will remember it now. Many thanks!
In the Uk they are building a new railway called HS2. The bridges and viaducts are almost exclusively reinforced concrete. How long will they last I ask ? I walk in Derbyshire and see stone built railway viaducts and bridges still in use after 180 years and some canal bridges that are nearer 250 years old. Were they not a good investment? Some other bridges constructed in the 1960s are now in serious need of repair as the corroding re-bar has "blown off" the surrounding concrete. Short terminism is to blame!
Excellent vid highlights these issues, but I suspect greed conquers all ?
Please do a video on shiny glass buildings. I'm convinced Foster & Partners are architectural terrorists.
Glass is definitely a good topic, and the so-called ‘transparency’ of these buildings
They made multiple designs for the WTC and literally every single one looks hideous.
@@the_aesthetic_cityAnd how these buildings get both cold in winter and hot in summer and thus are very energy-intensive. They didn't care about that in the 50s and 60s but somehow architects keep building them to this day.
Glass itself has a very long life, but we install it into metal frames in our buildings, and those frames will corrode.
Buildings made up of mostly glass are incredibly energy inefficient.
Low-rise sprawl doesn't work either though. Can we realistically build the modern super-talls with traditional methods and materials?
What a great video, in the architecture course there is not much mention of the disadvantages of reinforced concrete or other solutions like the ones in the video.
One thing that is rarely considered is the use of pumped concrete. The amount of water that is needed to set concrete is so little that it is far to stiff to be placed in moulds and to make adequate contact with the rebar. Adding more water makes very fine voids in the concrete when it eventually dries out (long after setting). This allows water and oxygen to be carried to the steel, promoting corrosion and spalling of the reinforced concrete.
Uhmm some key points
1. Ancient magnificent structures took as many as 2 -3 generations to build and with massive slave labor.
2. Materials used were more redly available.
3. To build such structures today would run into trillions of dollars.
4. Extremely less functional per square foot use of space
5. Mold mold and more mold. Horrid health hazards
6. The ones still standing are mostly historic attractions that have had millions and millions of dollars spent to maintain them. They crack and fall apart, foundations give out and mostly poor designs for weather protection.
7. What he or the bot said about steel reinforcement corrosion was correct. Except today the rebar is coated with anti corrosive materiel.
8. A concrete design is only as good as its installers and inspectors. The more people in the world, the more corrupt and incompetent, yet still only about 5% in every type of work.
9. Iv'e worked with structures for 50 years both new and restoration of old. I studied ancient architectures in college. Yes, they are magnificent beautiful works of art. But nothing that modern man has the resources to economically build today. Some materials no longer even exist that they used in some of those magnificent cathedrals.
Something i do not understand is why we do not use more recycled polymers, considering that most of the plastic is not recycled because of purity problems making it unusable for food packaging , but that post polymers have quite a decent weight to tensile strengh ratio, even recycled stuff, and on top of that would be made of garbage (so, the process of harvesting it would have a double use: cleaning environment and scavenging raw material sources ). I m especially thinking about polyethylene and polypropylene , like, imagine using some recycled HDPE and PP pieces in the same say wood was used traditionally,
We could also potebtially find an use for the desert sand that is too smooth for concrete by sintering it into solid glass-like bricks (heat treated glass can have a better impact resistance than unreinforced concrete) or by fully melting and processing it into fiberglass (fiberglass , even in the E form has above 3 gpa of UTS, so, it absolutely beat reinforced concrete s tensile strength in cartoonish proportions )
Especially when we consider glass s very high chemical resilience , abrasion resistance and recyclability (and we can either let it be transparent or make it opaque by adding things inside)
Like, imagine using the desert sand to make fiberglass, and then process recycled plastics into a matrix for such fibers and creating a low cost version of fiberglass composite for buildings (and the for part that need the focus on compressive strengh using heat treated glass bricks ) we could have something much stronger that still allow the same ease of design as concrete (probably more actually ) while having much superior durability
I love your work ❤️ your videos are always thought provoking
Very eye opening video!
I worked for a company that built kilns and furnaces using angle iron frames to support high temperature concrete structures. For the disk shaped lids of crucible furnaces which were less than 4 inches thick, we used stainless steel fiber mixed into the castings concrete.
The cured pieces were extremely tough and they could withstand hundreds of strikes from a sledge hammer. I had to break a lid out of its frame once because of a dimensional mistake and the effort needed was amazingly intence.
I'm a simple man: I see a new video of The Aesthetic City, I like it and then I watch it.
Same!
I wish the did more videos, it's a good influence on the world and needs more views.
9:26 - yeah, after the last war. Before that, with modern weapon systems any structure is nothing else but a target for a missile. Why one would spend a fortune on single building that can last a century if same money can be spend to build entire city?
Is modern concrete worse than the ancient-er ones? Or is it the magnitude at which it is used?
Main difference I can think of is the steel used in modern concrete, which definitely will rust over a certain period.
Ancient buildings like the pantheon didn't used it, as far as I know. Well honestly I guessed but I never heard of any giant roof renovation of the pantheon.
Funny to ask before the video is online 🤣
But yeah I am also keen to see more of this beautiful made content
Steel reinforced concrete faces rust issues when the steel becomes exposed. This puts a life expectancy on all reinforced concrete. Unreinforced concrete can, in theory, last forever.
The Roman concrete also used volcanic ash for better composition.
@@bart_u They also had to heat their volcanic ash concrete mix to make it work properly, which would be kind of expensive for us.
@@JohnFromAccounting then why modern builders used the steel at all if its worse ?
I wrote a paper on this topic earlier this year, good to see this is getting attention!
I'd be interested in reading it...
This is all good and well, but noone talks about the price. Construction with such tech will cost x5/x10 the current price. And noone is gonna go for it for economical reasons - this is just isn't worth it. It can be worth "globally" but noone is planning ahead for hundreds of years.
And yes, this will require much more manual and highghly qualified labor, which is getting more and more expensive every day.
Fantastic video! Besides all the ecological and structural problems of the concrete the buildings are built of today it is indeed a very unappealing looking material. Especially when it comes to brutalist or in some ways also contemporary architecture. Anyway, continue your great work!
The human species isn't evolved enough to incorporate closed loop/full life cycle thinking into its activities.
We will need to if we want to keep growing as a society
So we have devolved? Because for many centuries we absolutely built in such a manner.
I kind of know, that in realistic and economical sense, and with current population, concrete/steel is kind of essential to house all production and infrastructure (and even despite that, there is housing price issues as well). And despite the video being pretty biased against modernism and not mentioning the downsides of natural materials and techniques of buildings, that are longer/more expensive to build, not as effective at insulation+installation of commodities like water and electricity, and not even mentioning the changed modern view and lifestyle, focusing less on cultural values and more on efficiency, and even using unlivable pavilion as example as well... I still admire the spirit.
Modernist philosophy of architecture is more of a problem than cons of reinforced concrete, and that philosophy also influenced modern design standards. Reinforced concrete definitely has it's problems, but you can't advocate for old building techniques without considering earthquake, soil conditions etc. It can be very misleading for architects and investors to think they can build unreinforced masonry building in seismic area. You cannot economically design for earthquake loads and expect no (high) tension forces in your structure. Not to mention load distribution through diaphragms, uneven settlement of foundations etc. Reinforced concrete enables relatively simple and cheap earthquake resistant buildings and fixes a lot of other problems buildings use to have. If standards (Eurocode etc.) were different, durability can easily be +100 years or even more for RC buildings with smart details and concrete protected from exposure to negative influences as much as possible. I'm all for traditional and beautiful architecture, not this modernist crap that is being built everywhere, but it needs to be adapted for 21st century safety standards. We should combine following old principles of following forces in our structures with using traditional materials as much as possible, but strategically combining it with materials like RC, steel and timber to build beautiful, long-lasting buildings resistant to earthquakes, high wind loads etc.
Reinforced concrete isn't going away anytime soon due to it being such a great material. The problems cited are nearly all issues resulting from neglect and not issues with the concrete itself. Highway bridges are exposed to extreme weather, nonstop traffic loads, and rock salt dumped on it by the ton, but still last for many decades. If the bridge had a roof and sheathing to keep it dry, was climate controlled, and only had people in high heels and loafers walking on it, I believe it would likely last for centuries.
There's always Stainless or basalt rebar.
Excellent video. Spauling is a big problem here in Florida - thousands condo owners have learned this lesson the hard way.
Great video. The idea of working with nature instead of merely exploiting it, has bearing on all the arts, where modernism in any form has worked against nature: against human nature.
A vid where we say "concrete" has this long term problem, then explain the problem is the steel...
While the video did focus on the detrimental effects of rebar corrosion on concrete it also briefly mentioned some of the degradation processes that are inherent to Portland cement's hydration bonds and porous nature. Much of the Portland cement empire/industry exists as desperate(ly profitable) efforts to overcome its fundamental flaws with admixtures (e.g. water reducing plasticizers) and supplemental materials (e.g. alumina-silicates to take transform excess alkali from being detrimental to advantageous). Make no mistake, the problems (and thus short-term profitability and long-term planned obsolescence) of Portland cement result from its calcium based chemistry. It will never be a sustainable building material and every effort should have been made to develop far superior alternatives like alkali-activated alumina-silicates, introduced by the Romans and rediscovered back in the 1950s by the Russians and used for years for things like bomb-resistant bunkers by the US military. Unfortunately, attempting to maximize private profit/power guarantees that solutions to problems which minimize complete life-cycle costs will be systematically and resoundingly opposed, obfuscated and otherwise buried until the real costs of uncontrolled capitalism become catastrophic (e.g. the currently changing climate).
What about hempcrete replacing concrete? What would be the drawbacks there, other than ending the industry that profits the few while damaging the earth? Growing the plant also sequesters CO2.
10:13 60% is used in China every year. Because every 40 years they tear down the old bridge.And build a bridge 3x bigger.Increase gdp and create jobs for many people. #Planned obsolescence
What about doing something to improve the steel beams used in reinforced concrete to make them anti-rust or free from rusting? Then there would'nt be expanding rusting steel beams that becomes more prone to breaking that exert forces from within to weaken the reinforced concrete.
Just so you know, for future videos, we pronounce the T in "béton bruT" in French ;)
French is hard 😭😅
@@the_aesthetic_city 😂