Why SpaceX Cares About Dirt
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- Опубліковано 1 лис 2021
- Why do structures big and small sink into the ground, and what can we do to stop it?
Before the so-called Starbase supported crazy test launches of the Starship spaceflight program, it was just a pile of dirt. After nearly two years, they hauled most of that soil back off the site for disposal. It might seem like a curious way to start a construction project, but foundations are critically important. Building that giant dirt pile was a clever way to prevent these facilities from sinking into the ground over time.
Errata:
1. The SpaceX South Texas Launch Site is located at Boca Chica near South Padre Island (not near Boca Chica on South Padre as stated in the intro).
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The first sentence contains an error. Starbase is in Boca Chica, not South Padre Island. I know because I'm there.
@@GalenMatson Thanks for the correction. Those prepositions were inadvertently switched! I added this to the video description.
Thank you for the great video. Stable ground is a topic dear to my heart, coming from the Shaky Isles. A great companion to this video would be on the topic of liquefaction from earthquakes. Perhaps with a practical experiment to show how different soil consolidation methods can mitigate this problem.
Hey everyone, just wanted to remind you that the flat earther above doesn't care what you say to him, he just wants to waste your time. Whatever you send to him will be ignored, so just don't engage.
If you read what he wrote and are confused, remember that every point he brought up can be completely explained by the existence of gravity, which is easy to verify. If gravity doesn't exist, the millions upon millions of people who have ever taken some undergraduate physics are in on the conspiracy, because they've all had to replicate the Cavendish experiment.
Remember kids, we are all in geostationary orbit around Earth using our feet to lithobrake for station keeping so we don't fall through the core.
Soil settlement: "If your building was built too heavily for the ground it's on, you may be entitled to compensation..."
I too picked up on that (unintenional ?) pun ;)
This sounds like a law firm ad that could actually exist though.
Nice
Dozer dozer and fritz: mess with the bull get the horns
@@SerbanCMusca-ut8ny Care to explain to a non-native?
I have done dirt work my whole life. Florida is mostly sand so we would have to haul in clay and use a mixer to blend it to create a stable base. Very interesting video.
no kidding!
I’m form upstate NY, I didn’t know that about Florida. That’s cool
Sounds like a PITA. Do you have to have it tested before and after compaction? Or can you "eye ball" the mixture ratio, process, and backfill then test for moisture and compaction numbers?
Sorry, I don't quite understand, why would you want to introduce a soil more prone to consolidation to your foundation?
@@everythingisscience658 for better compaction. Have you ever tried to get 100% sand to pass density?
I'd love a "Why ____ cares about ______" series actually.
It would pick an industry or a specific job in a construction industry, and go in depth about a specific variable they need to control. It might actually be helpful for people going into that field too. "Why boom operators care about wind direction" would go into the designs, proceedures, and information that boom operators need to understand in order to operate their booms in high wind
I personally don't like it , it feels a bit click bait ( misleading ) as in this example caring about dirt settling is in no form unique to SpaceX .
This type of misleading slightly lowers my respect for the channel , but the great content currently overwhelms that Factor
@@nhpkm1 In no way is it clickbait.
@@nhpkm1 I understand your view, and generally agree, however I would say UA-cam is to blame for it. Cf. Veritasium "My Video went viral. Here's why".
@@xeuxixiliak8417 it is slightly . As it implying that it's unique to SpaceX.
It's like why do world class athletes eat food ?
@@patrikgubeljak9416 I agree , but I and assumably many others would of clicked on more appropriate title " why do companies send a lot of money just on dirt - geo engineering"
I often get asked why I’m watching things such as this video when my career is evolving into an IT profession and not so much an engineering one, and my answer has always been “it’s always neat to learn something new.”
It's not much, but it's honest work
I have always wanted to learn about something rather than sit around and watch people act.
Agreed I'm the same way, and honestly you'll never know if the info will come in handy. I do IT for a medical device manufacturer and all the medical youtubers have helped me visualize how customers use our devices.
Who knows maybe one day I'll be in construction IT, it's all interesting and wonderful to learn either way!
I’m a medical doctor and I love these videos. It’s always fun to learn more. Maybe even more so when you don’t need it. ☺️
Same, except I wanna enjoy my dinner a bit more
Now I know why they were “just moving dirt around” at Tesla’s Giga Berlin site. Thanks, Grady.
Always learning.
As someone who's in the process of repairing a sinking foundation from bad drainage, this has been extremely helpful to understand what's going on under my house. Thank you!
Been there. Done that. Not fun.
2:38: "Stress does a funny thing to the soil. I mean it does some funny things to us all, but soils too" - that's an amazing quote.
Little bit too close to home, actually.
Y’all remember that song
“Every step you take… induces stress in the subsurface”? Classic!
Subsurface will be watching you
Every move I make, every step I take, I'll be compacting you.
Im placing a restraining order on the subsurface
@@arifhossain9751 best wishes, my friend.
I was about to type that! (Damn it! 😅)
“Not that you’d want to go swimming in it [dirt].”
Oh, darn, I was really hankering.
XD this thread
We'll all eventually have a soak in soil. So keep your hopes up!😃
@@jamesa7506 Got dark real fast. Nice one though 😂😂😂
In some areas in and around Berlin, the ground water level is so high, or the basements so deep, that the foundation walls and floor are sealed watertight, and enough weight needs to be added to stabilize the structure so it doesn't end up basically floating.
This is a common issue in the Northeastern United States. I drill wells for ground water control. We just finished a project where we lowered the ground water so a sewer structure could be installed and covered before the water level returned and caused it to float.
This is also why when people decommission an in-ground pool, it is supposed to be broken up and not just filled in.
If is not broken up, it can, years later, float up out of the ground, sticking an unsuspecting new owner with the cost of removal.
For some major building projects in Berlin, especially for major hi-rise, office/transportation/retail complexes, there's been a system of either ramming modular steel retaining wall segments to mark out the footprint of the construction, or drilling out successive columns and filling them with grout/concrete to form a wall, then excavating the building site. When the ground water flooded hole is large enough, a pontoon is brought in to float the excavator, and when the sub-ground excavation is finished, walls and the basement slab are poured, made watertight, and the water pumped out so the rest of the interior structure can be constructed. It left some epic pits for things like the Potsdamer Platz complexes... Also, for tunnels, at times pre-cast segments are placed on the ground, and then the sandy soils are made to become a slurry, and the modules sunk into the ground until at the proper depth and orientation. Where TBMs or direct mining have to be implemented, the ground is frozen, so the tunnel doesn't start to flood before it can be sealed...
Common issue around buildings sites near bodies of water. Try building a resort pool or basement near the ocean, you end up needing a whole lot more concrete to prevent it from popping before it is filled...
I worked at a constuction site in Sweden where we built a 14 floor high wooden structure with a concrete basement below ground water level. The building was too light to stay down by gravity alone, so we had to screw it down to the bedrock with a bunch of 6 inch screws ^^
...that's 6 inch in diameter by the way, the hammerdrills we used had an 800hp compressor just to drive the hammer action :P
Oh no, Grady is going to build a rocket launch pad in his garage.
Oh yes, Grady is going to build a rocket launch pad in his backyard.
Just a very very small one
Do it Grady 😏
@@Lizlodude with googly eyes!
My dad works in this field, soil/geotechnical engineering. It's nice to see something mainstream to show the importance of this as many homeowners don't understand how important this is to help keep the building intact and often question why they need to pay for this.
This has been "Why Are There Cracks In My House After I Built An Addition?"
I'm an IT guy and never though I'd be interrested in "vertical soil wick drains" and "surcharge loading", thank you for making this fascinating video.
fun fact: A city in the netherlands also has a less known leaning tower that occurred with the same/similar issues, the tower is actually kind of bent since halfway they started building straight again to compensate
Same with the tower of Pisa actually, it has a slight curve to it because it took so long to build
You mean the Scheve Jan (Crooked John), the tower from the Oude Kerk (Old Church) in Delft?
(and to those wondering: yes, there's also a New Church)
@@daanwilmer or Oldehove in Leeuwarden perhaps ... but there I think they just stopped.
I wish I had watched this video about 40 years ago before building lots of slabs and structures in East Texas, where we have both clay and sandy soils to deal with. Most folks around here are do-it-yourself types, and soil engineering is just experience based for non-commercial projects. Sometimes things work out OK and sometimes they don't...
Eeyup. That good ol' Red clay. Used to live in Hallsville, whereabouts are y'all located?
@@IMRifley We're just south of Marshall
If nothing else this does make for a very funny anecdote.
Probably needs lime if you have a ton of clays and silts
heh heh. Call Olshan
"Stress does a funny things to soils. I mean stress does funny things to all of us..."
Taking deadpan humor lessons from Technologyconnections I see.
The two of them have the same sense of humor as me. I think it's one of the reasons I love both channels.
This "Why Does SpaceX Cares" "series" is such a good idea. I love it
I live in Las Vegas and they just started building a new subdivision by my house and they have like 10 giant mining dump trucks building a 3 story mound of dirt for the last week. I was so curious as to why! Thank you for this video and your perfect timing.
"Stress does a funny thing to soils. I mean, it does some funny things to all of us, but to soils too."
This cracked me up far more than it should.
Grady posts this 10 hours before my geotechnical engineering exam because he loves me
Im an engineering technician that works for a 3rd party testing firm. Stuff like this is right up my alley, I too would love to see a video about rammed aggregate piers.
As a geotech engineering geologist, I've been waiting for this practical engineering video for years! Great video. I get asked very often what I do for work, I'll have to start showing this video to people.
If you have been asked what you are doing for years and haven't come up with a viable answer for that. You probably aren't very charismatic so here is a good channel for you:
Charisma on command.
I am a consulting geotechnical engineer too. I mostly tell people that I squish dirt and write term papers for living.
@@SuperDeinVadda damn. Tf is your deal😂
Would love a video on "Rammed Aggregate Piers" as another alternative to dealing with compressible soils. I read Tesla's Gigafactory in Austin is using them to handle the local adverse soil conditions so common across Texas. They don't go to bedrock but seem incredibly stable.
Keep up the great work!
@SMA Productions The particular system Tesla is using is called "GeoPier." That's all I know.
Usually we use piers when a good layer of soil is deep and we need it as anchor points for the foundations. Piers are super stable since they are surrounded by soil, that soil also gives a lot of friction to the piers helping them distribute loads into the ground
@@jigui2669 Thank you! I guess I'm mostly interested in the "rammed" aspect of how Tesla's piers work. A video from GeoPier shows the aggregate spreading out laterally. I wonder how that affects the stability of the adjacent soil.
@@jigui2669 I also wonder about why you might go with a wider/shallower aggregate pier vs a narrower/deeper solid pier. Is there a critical depth for bedrock where narrow solid piers become impractical?
What you're referring to is also known as a rubble trench foundation. They have been around a very long time and were originally pioneered in America by Franklin Loyd Wright.
That is probably the best layman-compatible introduction to my job I've seen so far. Thanks! Here's some numbers from one of my projects: consolidation time with overloading only - 50-100 years. Consolidation time with vertical drainage: 6 months. Expected settlement without any preconsolidation: several decimeters. This was for a harbour train yard atop 10 meters of organic clay. And now I'm trying to build a bridge on similar soil. This time it'll be piles to the rescue, I guess.
Back in soils engineering class (~ 1970) we had a problem to determine how long it would take for 90% of consolidation to occur. This was a beginner class and no one had any idea of what the answer should be.
The equations were somewhat complicated. When we turned our papers in, I asked a couple others what they got for an answer. One guy had an answer of 7 minutes and the other had 100 years. I had about 8 years and wondered if I had done it completely wrong. Turned out the answer was about 10 years, so I didn't feel bad then....but 10 minutes or 100 years? Again, we had no feel for the amount of time required...just analyzing the problem and plugging numbers into equations. Also, this was before electronic calculators.
I now know why there were pipes or "wicks" sticking out of the ground at a new fly-over point near the airport. I always wondered what and why they did that. Thank you sooo much for making me smarter today (pun intended).
Yes please do more from SpaceX's Boca Chica facility! There have been so many cranes and infrastructure projects that I want all the civil engineering answers.
Bro. I love you channel. Here’s some reasons why:
1) I graduate in December in civil engineering.
2) You present the information in a logical flow and make it interesting.
3) The lighting set up you have in your studio has gotten better and better over the years.
4) I feel smart watching your stuff. 😂
Thanks!
As my first job was as a soil testing technician back in the early 90s, this is bringing back some memories.Consolidation was one of the fundamental tests undertaken, but all sorts of other physical shear and compression tests were also in the arsenal of the lab.
This reminds me of a documentation of the construction of a large school building, this may be a topic for a future video - because large buildings have the exact opposite problem during the construction phase (building floatation). I picked up a conversation snippet where the engineer stated that the "bathtub" (foundation & cellar of a large school building with 4 stories) has gotten it's roof and that it's now heavy enough that it can't float up due to groundwater pressure when they remove the sheet pile wall. This boggles my mind that this is actually a factor they have to consider during construction... 😲
I used to build concrete pools and sceptic tanks, even though we might have 30 tonnes of concrete in a pool, on a few soil types I would include a stipulation on the guarantee that the pool was never to be emptied, as it would float, one small 3000l septic tank we had to pour a 8 tonne slab on top as it would float even when full. The wet ground soil when tested was close to 2500kgm3 tank was 1800kg m3 and water is just 1000kg/m2 creating 5 over tonnes of floatation force.
And people still go "reeeee" about large projects taking a long time....
@@bobbypatton4903 To be fair, large projects cause disruption and disruption is uncomfortable. They will always REEE and that will maintain the pressure to innovate in construction. Prefab has come so far not just because the cost of making a building out of prefab modules is less, but also because the opportunity cost of how much longer before the investor sees a return by making the project operational.
"when we build stuff, we don't want it to move"
*Expansion joints have entered the chat*
To be fair, we wouldn’t need those if things didn’t move
"Kranplätze müssen verdichtet werden"
German meme originating from an short TV snipped where an German site manager rages about uncompacted soil. Because "places for cranes need to be compacted" :)
After looking at the thumbnail I knew I would find this quote here.
I'm learning German right now and I'm so happy to find this meme.
The compaction of the soil in your test is also uneven because of arching effect: weight is redistributed towards the walls of the oedometer and the soil sticks to the walls thanks to Coulomb's friction.
Same thing happens in grain silos.
On one hand it limits the pressure on bottom grain. On the other, it strains the walls.
9:24 it’s interesting to me that in many cases piles don’t need to go anywhere close to bedrock because it is the friction of the the pile against the surrounding soil that bears the load of the foundation
I've been in the earthmoving business in south Louisiana my whole life and have been a space nerd for just as long. I can't express how excited I was to see the title of this video. I've done many large building pads that required surcharges.
It takes a particularly skilled person to talk about dirt and make it interesting great vid
Watched on Nebula, but came here to say thanks for making this video. I asked for a few more geotech videos in your last Q&A and this was great.
Thanks Grady for making this video!!! Love whats going down in Boca Chica and stoked to see content about it on Practical Engineering! :)
SpaceX barely had anything to do with this video, but I'm sure that it brought in a lot of viewers! ;D
Hope the channel continues to grow..
Lime soil stabilization is a great way to remove the water and improve consolidation in fine grain soils like silts and clays. Used in lots of large foundations and highways.
yasss more space and spacex stuff, love it
Yass more dirt and infrastructure stuff, love it
Meh spacex stuff
My gosh how do I love the practical engineering videos! Each is a peaceful, calm and smart masterpiece. An anti-anxiety pause in a middle of a daily hassle, teaching something interesting and assuring each time. Great job!
Not gonna lie, I’m disappointed this video wasn’t sponsored by the upcoming Foundation series 😂
I'm disappointed that no Delicas were used for scale. How am I supposed to understand how large any of the things in this video are?
I don't think there are enough of us here to get this, but well played sir...
The first episodes are already out for anyone wondering. Definitely worth a watch imo
Foundation, as in Asimov's foundation?
@@broklond Yes. It's a TV series now, and a bunch of people think they've discovered some new and obscure thing that doesn't have a pre-existing fanbase.
I love the creative way he's using the "Olympic swimming pool" as unit of measurement
I absolutely love these videos, they open a world of problems - and problem solving I would never have thought about. It really goes to show just how complex so much of the rest of society, education, manufacturing, and so on has to be to do something as "Simple" as lay a foundation, or build a road! Thank you for creating these videos, as well as simplifying it enough so a layman an understand it!
Great channel! I always look forward to new videos!
These are top-notch videos. I work in science unrelated to civil engineering, and I learn something in every video you make.
Nice to see another deep dive into Spacex structures. Any chance of one about the rocket catching structure? (Just an idea)
your way of explaining these complicated concepts is incredible. you make it so easy to understand
You do a really good job on these videos. Wide range of real examples and the home made demos really boost the educational value, and the scripting and way you speak is easy to understand. Thanks!
"I mean, [stress] does some funny things to all of us..."
Is...is everything okay, Grady?
I love how one of the most advanced space vehicles looks like an enormous grain silo.
It bears a resemblance to other things too.
That was Mk.1 it was basically welded in a field by water tower guys. Ship 20 is a lot prettier, heat shield and all. Now the heat shield tiles just need to stop falling off whenever they fire up the engines...
Finally!! Thank you, I knew the basics of what they were doing but this gave me so much more!! Amazing video as always.
I am so happy you are doing videos on SpaceX! two of my favorite things combined!
By and large, your audience finds very little fault with your scientific rigor when conducting demonstrations of principles and mechanisms.
Like we say, if a geotechnical engineer wasn't involved, it either floats, fly, or falls over
Excellent video as always Grady!
I have recently joined and started watching the content covered on the channel. I'm not in any way involved in any of the subjects covered I'm just a curious person. I had a very basic knowledge of the topics covered and when I said basic I mean I knew they existed. I have gained a more meaningful basic understanding of the principles covered on the channel. And I thank you for breaking it down really enjoy the channel.
I would love to see a video about structures planned life span and the different elements that go into a life span and how they're extended
Today I learned: Grady sure does love his Olympic sized swimming pools.
glad I'm not the only one who noticed that haha
@@kevinbissinger It's one of those common comparison units, like the weight of a blue whale or elephant, or the length of a commercial passenger jet or school bus.
Channels like these keep me coming back to youtube. One of the few gems
I’m loving these series on soils!!!
Love your channel, just the right length and compactness of all info👍🏻
you could say his research is well consolidated.
Small correction at 0:03. It’s not on South Padre island it’s just near it, in fact, it’s much closer to Boca Chica.
If anything the sentence would make more sense the other way around "...South Texas Launch facility in Boca Chica near South Padre Island"
Just learned about different grades of stone today for use as ductbank material. Thanks for teaching me more about compressibility, Grady!
all this soil science that was needed in various places explains why NYC had the first super tall skyscrapers in the world. They had that nice hard granite bedrock under Manhattan.
The audacity of Grady to release a new video as I’m drifting off to sleep…
"I built a little demo out here in my garage..."
- Grady's raison d'etre
I really like your videos. Not just because it is spaceX but because it is an great way to explain more about materials like soil. I also really like the analysis you make on accidents and disasters like the dam breach. Keep it up!
I love your educational and entertaining content Grady, thank you!
I remember watching how they built the WTC bathtub foundation, it was really interesting. RIP, to all those who were lost on 911, and peace to their families.
I like this video so much that my appreciation for you making it could fill an olympic sized swimming pool
Thank you for an awesome video that explains and demonstrates (primary) consolidation, differential settlement, and measures to avoid settlement problems! It has great content and simple enough to show during introduction of soil mech classes.
I hope you can one day cover the ongoing settlement that occurs after the end of primary settlement due to creep, crushing of soil particles, and more soil structure rearranging, etc. Although many forget this part of settlement but not accounting for them can cause issues to structures and surroundings.
Coming back home from out in the country, yesterday, I saw an old community hall. It's an old stone-faced building and one end had settled significantly, causing it to crack and about a quarter to separate. At the top, the gap was probably around 8". It's a shame to see old buildings fall apart like that, but it goes to show that the ground wasn't properly prepared for the foundation.
Great video. As a professor on the topic, I have a pet peeve with the settlement x time plot. I like to plot the settlement axis inverted, as the soil surface goes down with time. That is how I learnt from the best Soil Mechanics book of all times: Soil Mechanics from Lambe and Whitman.
Makes sense
Oh, I dunno about that -- what about Terzhagi & Peck? Holtz & Kovacs? Joseph Bowles 5th ed.? Coduto?
"Settlement Happens" is a good Tshirt idea.
I'm wear Practical Engineering merch
"I built a little demo out in my garage"
Me: HE SAID THE THING.
Got a new demo here in my garage
Awesome work as usual, Grady!
This is a strange first comment on what has become one of my favorite channels in the last few months, but Morning Brew is awesome. And for me it's been particularly awesome. I'm changing careers from music theory professor to actuary, and the shift from the humanities to mathematics/finance has been arduous in many ways. Much to say there, lol. When I realized I needed to learn and be conversant in business-related topics - something of which I was almost entirely ignorant - I subscribed to Morning Brew about a year before starting the actuarial science program. I committed to reading it during breakfast. It was a bit disorienting at first, but after about a month, I had an expanding list of economic buzzwords, which made 3 or 4 of my classes much easier. I'm graduating this coming May (2022), so... fingers crossed on finding a job, lol.
I also have to mention how awesome this channel is. I've been interested in how things work since I can remember, but your content really opens my eyes to so much awesomely complicated stuff going on around us, which most people take for granted. The first vid I watched was about road design, and I was hooked. Keep it up!
So I recently constructed a steel I beam building on a hillside of a man made impoundment and when drilling for the anchors I found there were no piers(we did not pour the pad). I did not find this by breaking through to gravel. It was a rock catching the bit in 1 spot of the circle. Only 1 anchor did not go to spec depth even with an hour on that hole and every anchor hit rock with yellow to brown colored dust, no red. My question is that do engineers account for movements the opposite of settling? Or is the degree rocks are pushed up offset by the pad/building?
Yes, geotechnical engineers consider uplift and swelling. Many soils in the USA swell when they get wet, so in areas where this is a known problem, recommendations to mitigate the potential problem are typically provided. For many applications, the controlling design concern is uplift/overturning due to wind loads (consider wind turbines, etc.)
As Wally said. Also, Grady mentions his previous video about expansive soils and uplift that I recommend you watch.
Here in Colorado our soils are highly expansive so structures have to be built accordingly. I can't tell you about commercial construction, but residential construction has specific code to address soil expansion. You can't build a slab on grade here, you have to build a walled foundation with a gap between it and your slab so that the slab can move up and down. Wall framing on foundation levels is required to have a floating bottom plate that can also move up and down. Older homes built with concrete foundations before these standards were set always have cracked foundations and many aren't structurally sound anymore.
"certain soils expand when saturated with water"
Looking at you, Stuttgart 21, you overglorified train stop.
"Gipskeuper"
@@molunos8842 der quillt!
Loved the music and intro sequence this round! Ode to ye olde and trusty!
I gotta tell you... Grady. You get the point across.
Thanks for facts and explanations that I find quite understandable.
My best to you.
In the words of the Red Hot Chilli Peppers "I like dirt, I like dirt"
Thanks for sharing that highly relevant information 🤨
In the words of the 🌶️ peppers. "Space, it's made in a Hollywood Basement." Like I have said so many times, if you want truth, scrutinize movies and music. If you want lies and half truth at best, Watch the News.
"We're sinking! We're sinking!"
"What are you sinking about?"
I really enjoy your videos, thank you for sharing. Keep up the good work!
Practical Engineering is my favorite channel!
I can relate to this video as I live in North Central Texas where the soil around my foundation is mostly clay, so keeping it saturated with water is important in avoiding foundation problems. In the middle of the hot Texas Summer the cracks in the surface can exceed 3 inches. Needless to say, I use my irrigation system of drip lines to avoid this occurring next to the foundation. It's a cheap and easy way to avoid foundation problems.
Question about surcharge loading: if the imposed stress of the structure is less than that of the added material, can the soil expand again? Do you need to remove the added material at a specific timing to prevent this? How do you know?
The soil deforms plastically, so the VAST majority of the deformation incurred by the surcharge will not be recovered. It's like if you pull hard enough on a piece of metal (or plastic) where you get the necking... that deformation will not go back to where it was before. You have moved from elastic to plastic deformations. Maybe a better example is a piece of pottery clay... press your finger on it, and it will keep the imprint of your finger, it does not bounce back to its initial shape. That is why clay is great for pottery, because of plastic deformations, it keeps the shape you impose on it with pressure.
This being said, there WILL be some rebound (the soil is at least one order of magnitude less deformable after pre-loading), but the rebound will not be much and will be recovered quite quickly. In any event, since after removing the surcharge we proceed to the final construction, and if you remember that we kept the surcharge until such a time as we almost reached the the target settlement that was going to be caused by the structure, there is not much chance for rebound to happen before the soil is reloaded to get to that deformation it had already almost reached.
@@Tomm9y Heave in soil is not an issue of removing the load however. Swelling soils swell because of an ingress of water (note, only some clays are prone to swelling). They change volume a lot between getting wet and getting dry, and can indeed apply stress to a structure from swelling pressure. It is a completely different issue from recovering the deformations caused by applying loads to them.
While Texas I believe does have issues with swelling soils, the site of Boca Chica is basically at sea level, and it is unlikely that the clay there will get any more saturated than it currently is, and so swelling should not be an issue. Swelling is something that you worry about when your foundation is above the ground water table if you have a swelling soil and significant changes in the elevation of the ground water table over time.
I _love_ these engineering explanations of Starbase.
It's such a crazy project!
More SpaceX related science 😍 Loved the video
What happens to a building's high-clay subsoil that had to be compressed and drained prior to construction, but now the surface finds itself frequently under standing water due to flooding or - in the longer term - climate change.
Will the water eventually re-expand? Does this cause meaningful uneven forces on the periphery of a foundation?
Thanks!
If the surface still has the weight from a building on it, that will work to keep it compressed.
Beyond that, who knows exactly what the particular soil will do over the decades lol
Some clay soils do swell with increases in moisture content, and the swell pressure can be significantly higher than the structure weight. I have a video all about expansive soils.
It depends a lot on the type of clay in the soil and it's expansion ratio. If it's 2/1 (aka it swells to twice it's size when 100% hydrated) you'll be fine, if it's 20/1 you're pretty much screwed.
Dutch engeneers:
What do you mean "some" structures sink? Dont all structures sink?
I love the unit of Olympic swimming pools, OSPs. A unit only a few of us have any intuitive notion about.
Thanks for a great video, this channel is great!
But when they describe an actual Olympic size pool, what do they compare it to?
@@tncorgi92 Good point we could have a regress of size comparisons until we come across some agreeable measurement
Terrific video! This is what I was looking for to understand all the huge piles of earth that were brought into housing developments prior to any construction taking place, only to be removed later. Seemed a bit redundant, but now I can appreciate the science behind the soil compaction. Thanks!!
SpaceX + civil engineering - seems like someone engineered (pun intended) a great topic combo. I really enjoy your content; recent video about fixing a underground power cable was great - it had this Neal Stephenson cyberpunk vibe. If I may, I'd love to see videos about underwater pipelines/telecommunications cables (aka Cryptonomicon) or how CAD/digitalisation influenced civil engineering - maybe something about FEA. At any rate, great job!
Adding tonnes and tonnes of dirt was too logical, they should’ve just tipped a bunch of falcon 9’s upside down and launched them into the ground to provide the needed force. Much cooler way to do things.
I have to say, the fact that you can get a video about dirt to #26 on the trending list (at least as of when I'm looking at it) is a huge testament to your skill with these videos.
It really shows that you have made the lighting much better than in the beginning, kudos