Ooooh, dry pour update :3 Very excited structural engineer here. So wall of text incoming. You have been warned. First of all I see nothing wrong with your testing job with the concrete-strength-testing thingy (which is called a Schmidt hammer by the way). All in all I'm pleasantly surprised and also glad for having been more or less able to predict the results; and also the pitfalls of dry pouring. Pleasant surprise comes from your results. Which I could interpret right away as a European (SI ftw). One thing I feel the need to add: this hammer method tests surface hardness which directly correlates with concrete strength... in wet poured stuff. As you said the method can be ver unpredictable. The smallest inconsistencies in pouring, compacting, and wetting the slab have major effects on its final strength. Also in a lot of cases the inner part of the slab does not get properly hydrated. This means there will be uncured cement remaining in the slab reducing strength. All these results align with my opinion I established last year about dry pouring. Great for horizontal slabs without reinforcement and highly not recommended when: a) working with rebars - proper hydration across the slab is critical for the rebars to properly adhere b) building actual load bearing structure - we want the least amount of uncontrolled variables c) being prone to rush / half-*ss a job :) One more thing to keep in mind: cement content and proper hydration makes or breaks the concrete's resistance to freezing. Overhydration leaves a lot of pores / air pockets after drying. The top surface is the most critical in this regard both because water sitting there when done and because that's the surface you wet your dry pour through. If you work at a location that sees freezing temps be extra careful not to overwater your dry pour.
@@Fonok87 Awesome comment! I didn’t know about the over wetting leaving more pockets/pores. As a structural engineer, do you know anything about the closed cell expanding foam called Secure Set? It claims that concrete has approximately 6,000+ psi after 30 days and their foam has approximately 10,000+ psi after 30 minutes. I haven’t seen anything about it being used in load bearing or structural work but if that psi is correct, why not? I did find (on UA-cam) a couple in Arizona that built a geodesic dome house and covered it with a closed cell foam. They built the house in only 4 days. If this stuff is as strong as they claim, I’m thinking it could be an awesome material to use after disasters to quickly build structures for people who have lost their homes. Do you have any insight into this product?
I haven't heard of Secure Set but I'm in Europe so that might be the reason (I checked their site, they have no presence outside the US). The thing with these materials is that they tend to be waay more expensive than concrete which is the case here. Their 4 gal kit says it can be used to set 20 posts in a 8"x24" hole at a price of $132. Even if I omit the volume of the post (which is not insignificant) cost comes out to about $190 per cubic foot. Other materials might be cheaper but they all come with enormous R&D costs. Also concrete mixed at a plant can easily reach 9000 psi strength. When using literal tons of concrete to build a structure it means millions of dollars in cost difference. On the other hand, concrete needs at least a week before it can safely take a load. So it comes down to what you're willing to pay for the massive reduction in building time. Disaster recovery and critical structure repairs are good examples where getting results quickly is a priority above all else.
"proper hydration makes or breaks the concrete's resistance to freezing." So, is it possible to dry pour a base, leave 1/2 inch at the top of the form, then finish the job with a traditional mixture, for the remainder of the project. I'm thinking, if cement adheres to older cement, this method might prove to be a solution for the cracking and flaking. I'm not pouring any cement slab, nor have I ever done any cement projects. Just curious as to what your opinion might be.
Hey, I worked as a concrete QC tester for 5 years. I've never seen this rebound test before, so I looked it up real quick. Unfortunately, it is not an accepted method for strength testing. It looks could be within 25% of the real strength. The best way, would be to drill out a 4 in diameter cylinder, or cut a 2x2x2 cube, and break it in a machine with a load cell. You probably won't want to damage your concrete though. As for the delamination. Usually, I would see this if the finishers sprayed water on top after the concrete was mostly set up. Which is not allowed on civil projects.
I've been waiting for this video, and it's pretty much confirmed what I expected. As a Cement mason, if I poured any concrete as bad as that patio I'd ripe it out and replace it at my expense. As you said, these were experiments and the information is great! Honestly, I expected the compressive strength to be decent. But low compressive strength isn't the problem with dry-pours, it's the inconsistency throughout the slab. The delamination is a sign of some serious problems, specifically uneven hydration. Some parts were too wet (such as the top and edges, making them brittle and weak), some were just right, and some were too dry (such as the center, making it crumbly and prone to fracturing). The cracks on the edge are likely just ordinary concrete cracking that found a perfect fault line for a particularly nasty crack. The top and edges will get too much hydration in a dry pour, but the concrete immediately underneath them will be much better hydrated. The middle is underhydrated, meaning that well-cured corner will crack at the path of least resistance (the comparatively weak middle), leading to a complete break instead of a hairline crack. The unpredictability of dry-pours isn't a bug, it's a feature. If it's showing that much wear after ONE YEAR, I REALLY want to see what it looks like after two. As for the compressive strength, the only way to get an accurate test is to test a cylinder to failure. One way you could do that (roughly) would be to drill some core samples, stack them on top of each other, and test them to failure under a hydraulic press. It's still likely to have some decent strength, but that's not surprising. For example, layering beach sand between 1 foot by 1 foot sheets of window screen leads to a cube of sand that can hold up a car. It's called engineered earth. It's used for freeway ramps. Engineered earth will also have solid compressive strength, but it's not going to replace a home's foundation. Concrete will crack, but that shouldn't lead to any delamination or spalling. I've ground floors that looked crack free only to reveal a vast spiderweb hidden just underneath, but it was still cohesive. I'd struggle to fit the head of a needle into any of those cracks. The dry-poured slabs on the other hand look like they're struggling to hold themselves together. The difference between a dry pour and wet-poured concrete is the life-span, and I suspect even a good dry-pour will struggle to survive past 5 years.
Have you seen the video with the 86 year-old man mixing concrete quickly using only a tarp? The technique was amazing and easy. You should look it up... very impressive. Do a video for it, many will watch.
It is interesting to see the resulting psi on those dry pours. By your own words the unpredictability of the final appearance would be the exact reason I would never do a dry pour. Everyone has their own preference on aesthetics but I look at it from a standpoint that if you already paid for the concrete mix it proper and get a predictable result. I know some people love Jackson Pollock artwork but I don't want my concrete projects ending up like that. 🤣😂🤣 Good on you for doing the testing because it seems everyone else who promotes a dry pour never comes back later to show any real world updates.
Funny all of these imperfect surface issues in appearance..... I see in commercial wet concrete pours ... especially on side walks at new truck stops. Less than a year old .... lots of "deamination " and cracked broken corners
Love the fact that you went through all the different dry pours and tests. I was thinking, dry pour a base, leave 1/2 inch at the top of the form, then finish the job with a traditional mixture, for the remainder of the project. If cement adheres to older cement, this method might prove to be a solution for the cracking and flaking.
For the difference of 100 dollars for a mixer rental mixing the concrete is just the way tk do it. Unless you're looking to remove the patio within a certain time frame. Concrete was designed to be mixed and the negatives of not mixing are huge. Less PSI, the concrete doesn't gain strength over time when it's dry poured, it doesn't bond to the rebar if yoire using it which means that's causing damage over time not reinforcing it. There are many many more reasons to mix it and not dry pour it. Even in controlled environments where the concrete is dry poured then maintained with constant moisture for days it has these same downfalls. If you're concerned about pouring a large concrete pad, break it down into smaller sections. Concrete needs relief points, those lines in the sidewalks, and those can be done many ways, one of which is pouring in sections
@@VeggiesOutFront Agree 100%. The instructions are clearly marked on the bag. Deviating from the directions are problematic. I've never done a "dry pour", and I never will.
New Video 💡 : I have been building an off grid cabin & found secure set expanding foam for setting fence posts. (My back is loving NOT dragging heavy bags of concrete). The product website states that normal concrete has a 6,000 psi after 30 days and their foam has a 10,000 psi after 30 minutes. I don’t think my posts will ever move! It would be a very cool thing to check with your new toy. I love concrete but this stuff is only slightly more expensive (actually may be a bit less $ if you buy in bulk) and as we get older, those bags just keep getting heavier 😂. If this stuff is all it says, why aren’t we using it for foundations, etc? You have so much experience with concrete, I would love to see your input on this stuff! ♥️🕊
It would seem as if the dry pours that remained in contact with the ground, and therefore soaked up more water, where stronger. So I wonder if that would be an additional variable to consider.
This is really good to know. I stayed to watch the math makes a good argument for dry pour. I have a chicken house I plan on cleaning out with drain lines so every so. Often I clean the floors and hide it out. Thanks for the exoeriment
Maybe a good project to try out - Make a 2'x2' form, fill it 75% dry concrete, mist it really well, add some type of metal reinforcement and then fill the remaining 25% with wet concrete which will allow you to finish it off nicely and prevent top layer separation. I would watch that video. 👍
Looks great. I like the "decayed" look too, especially in older-home landscapes. I'd love to see you try some "Portland cement paint" and coat some concrete areas with that. Maybe it will help fill those peeling areas and cracks.
The top chipping off the concrete is caused by the inside of the concrete drying slower than the top. This is why people use spray on cure or do a wet cure. It essentially slows the curing process on the surface so the concrete dries more evenly. Since a dry pour doesn’t have the water evenly distributed through the concrete it isn’t activating the lye equally and that’s what’s causing most of these problems.
I think the reason you get the flaky surface on the concrete dry poor is because of the initial misting before soaking. I’m curious if that would still happen if you did an extended initial misting that really really saturated the top layer so that the thickness was closer to a quarter of an inch or even half inch instead of a 16th or an 8th of an inch.
not sure if this will help or hurt but i live in florida and there is a road from naples fl. to ft. lauderdale called alligator alley and when it was built back in the early 60s all the bridges and there were many!! had bagged sakcrete used at the ends of each . they were laid att approx. 45deree angle up on the dirt . they were still there in the 70s when I75 replaced them .!!!!!
They lasted better than the road did, that's for sure. You would think with no frost heave or freeze cycles the roads would be better here, but nope. Cape Coral especially, the roads here are trash for how much they tax us here.
As a professional user of the rebound hammer, you did pretty well, but you didn't keep it perfectly at 90° at least on the first one. It probably wouldn't affect the results much. Great job!!!
QUESTION???? What are the results on the the one that are delaminating?? Is there a possibility that the one you tested in the middle was able to get more water so the outside ones may be lower?? Just wondering I love doing these types of tests so I would have don’t multiple tests around the patio “slab”
PSI strength will depend on the concrete mix that you used, do you remember what you used? That would tell us more about what the manufacture expected it to be in normal use as opposed to dry pour.
I need to fill in a large area that had large raised planters for40 years , and had to be torn down because they were no longer structurally sound, aggregate cement was poured around that. I’ve pondered anything from brick pavers to artificial turf. I wonder if this is the solution? And what would be the best way to do a dry poor inset the empty space?
CORRECTION for those who think they learned something physics-y. A "Newton" measures force, not pressure. That device he's using measures Newtons per square millimeter, not Newtons. It's right at the top of the chart he shows. 1 Newton per square millimeter ~= 145 PSI. Those extra digits past the decimal point given for the conversion don't mean much IF... IF... IF... the way that device obtains its result is affected by the local value of gravitational acceleration (e.g. ball drop), which can be +/- 0.2 PS1 between Seattle and Los Angeles due to the "centrifugal" affect of the rotation of the earth. (This is why you were tortured with "significant figures" in science class).
I had concrete steps in a house poured the "right way" and the top started flaking off too, so Concrete is never 100% consistent regardless on how you pour it.
Awesome vid, so interesting. I have been doing a bunch of dry pours using 24/6 rapid set. Says 6000 psi on the bag. I wonder how much a difference this makes as opposed to the normal concrete mix. I think you used the 24/6 rapid set for one of your dry pours, but I cant remember which one.
I can imagine dry pour being great for a walkway like on the side of a house, where people don't care how it looks as much. I think the compression test might be flawed, but I'm not professional. The only reason I say that is because you're testing the top of the dry pour and that's the main part that got water. As we saw in some other dry pour videos, the bottom doesn't get nearly as saturated and I don't know if the improper saturation makes it worse or not.
I worry about the methodology here. AFAIK that type of tester can only measure the compressive strength of a shallow layer. If the top layer is fully cured (exposed to enough moisture to do that) but an inch below the surface is still dry, all you have is a hard layer on top of basically dust. It might be fine for patio furniture but if you used this method on anything that actually requires a certain thickness (e.g. 4", 6", a footing, etc...) you could have a dangerously weak core under a thin, hard shell on top. It would be interesting to see you use this same tool on a test pour or two, say 1'x1'x4" and maybe 1'x1'x6", then cut the test piece with a disc and test the sides/bottom. I would bet if you tested enough thicknesses, you'd probably find some maximum that can be used as a rule of thumb between "just DYI it with a dry pour" (pavers) and "that really does need a wet mix" (garage slab). If the center isn't going to cure past, say, 3" thickness, you might as well just lay down a (cheaper) bed of sand and do a thinner layer of concrete over that...
Thanks for revisiting these dry pours. I think the delamination is a result of your dry pour technique. I went back to watch the video of you dry pouring the blocks, I think when you misted, you put way too much water on the concrete, and the after the mistings, it's supposed to be a shower not just pouring out of the hose. Also, I don't think you watered them enough, supposed to be 2 showers per inch, 1 every hour. So 8 showers since you have a 4" thick block, 8 hours of showering.
Dry pour should be strictly used for post setting that does not require major tensile strength. Other than that it is a waste and a matter of time until it will require to be torn up
So it has been 39 months since you quit your job and become a full time UA-camr. In that time, I have seen, I believe, 68 videos. Are you still happy? Does it pay enough with putting out almost 2 videos a month? I know it helped that you had a decently large audience before quiting. Any advice for someone considering the same?
OK ok ok So, what would happen if you did a dry pour in lifts. Like 2 inch lifts minutes a parts. So just my brain rattling around. Keep up the great work.
Your conversion of Newton to PSI is dubious. PSI essentially maps to Newton/unit area. So, in order to do this conversion, you need to have some kind of surface area term you divide by. You cant just say 1 Newton = this many PSI because these are not the same kind of quantity. Namely, a Newton is not a unit of pressure, but a N/m^2 is. Can you give more details?
I mean, my take-away from this video is that dry pouring can work, but it's unreliable, and typically results in much weaker (and uglier) results, so, outside of some niche circumstances, you should basically always do a traditional pour.
What sucks about this is that your patio was set up perfectly to just do small mixed batches. You could have shown people the proper way to do a project out of their league. It should be easy to break up and remove in a few years
So, the conclusion is the same one I came to. Tricks on the internet aren't proof. It was started by DIYers trying to trick people to subscribe, to make money. I was a contractor and I'm a UA-cam influencer- it's bogus.
Dry pour is just unpredictable.. inconsistent. As shown rapidly by the surface defects in the patio. Sure. you can get places that work well. But you get too much that goes wrong. Just too easy to use a Harbor Freight mixer and do it right.
These numbers are garbage without correlation to core sample test. It is extremely important to note that the hammer must not be regarded as a substitute for standard compression tests but rather as a method for determining the uniformity of concrete in the structures, comparing one concrete against another, and reducing the number of core samples. You also have too much scatter in your data and thus the data should be collected again. Additionally, a newton is a unit of force and not pressure, so you need an area to be able to convert to PSI (Pounds per Sqaure Inch). I assume your measurements are Newton per sqaure millimeter, but not sure since you didn't mention it.
There is a concrete guy who does more thorough testing and it’s nowhere near the strength of poured crete never mind the looks. For those saying it looks “good” it’s only a year old concrete lasts for (about) 100 years and I can imagine what it’ll look like after (only) 20 years when failing when (in theory) it’s only a baby
This is the video I have been waiting for!!!!
Ooooh, dry pour update :3 Very excited structural engineer here. So wall of text incoming. You have been warned.
First of all I see nothing wrong with your testing job with the concrete-strength-testing thingy (which is called a Schmidt hammer by the way). All in all I'm pleasantly surprised and also glad for having been more or less able to predict the results; and also the pitfalls of dry pouring. Pleasant surprise comes from your results. Which I could interpret right away as a European (SI ftw). One thing I feel the need to add: this hammer method tests surface hardness which directly correlates with concrete strength... in wet poured stuff. As you said the method can be ver unpredictable. The smallest inconsistencies in pouring, compacting, and wetting the slab have major effects on its final strength. Also in a lot of cases the inner part of the slab does not get properly hydrated. This means there will be uncured cement remaining in the slab reducing strength.
All these results align with my opinion I established last year about dry pouring. Great for horizontal slabs without reinforcement and highly not recommended when:
a) working with rebars - proper hydration across the slab is critical for the rebars to properly adhere
b) building actual load bearing structure - we want the least amount of uncontrolled variables
c) being prone to rush / half-*ss a job :)
One more thing to keep in mind: cement content and proper hydration makes or breaks the concrete's resistance to freezing. Overhydration leaves a lot of pores / air pockets after drying. The top surface is the most critical in this regard both because water sitting there when done and because that's the surface you wet your dry pour through. If you work at a location that sees freezing temps be extra careful not to overwater your dry pour.
@@Fonok87 Awesome comment! I didn’t know about the over wetting leaving more pockets/pores. As a structural engineer, do you know anything about the closed cell expanding foam called Secure Set? It claims that concrete has approximately 6,000+ psi after 30 days and their foam has approximately 10,000+ psi after 30 minutes. I haven’t seen anything about it being used in load bearing or structural work but if that psi is correct, why not? I did find (on UA-cam) a couple in Arizona that built a geodesic dome house and covered it with a closed cell foam. They built the house in only 4 days. If this stuff is as strong as they claim, I’m thinking it could be an awesome material to use after disasters to quickly build structures for people who have lost their homes. Do you have any insight into this product?
I haven't heard of Secure Set but I'm in Europe so that might be the reason (I checked their site, they have no presence outside the US). The thing with these materials is that they tend to be waay more expensive than concrete which is the case here. Their 4 gal kit says it can be used to set 20 posts in a 8"x24" hole at a price of $132. Even if I omit the volume of the post (which is not insignificant) cost comes out to about $190 per cubic foot. Other materials might be cheaper but they all come with enormous R&D costs. Also concrete mixed at a plant can easily reach 9000 psi strength. When using literal tons of concrete to build a structure it means millions of dollars in cost difference. On the other hand, concrete needs at least a week before it can safely take a load. So it comes down to what you're willing to pay for the massive reduction in building time. Disaster recovery and critical structure repairs are good examples where getting results quickly is a priority above all else.
"proper hydration makes or breaks the concrete's resistance to freezing."
So, is it possible to dry pour a base, leave 1/2 inch at the top of the form, then finish the job with a traditional mixture, for the remainder of the project. I'm thinking, if cement adheres to older cement, this method might prove to be a solution for the cracking and flaking.
I'm not pouring any cement slab, nor have I ever done any cement projects. Just curious as to what your opinion might be.
@@robertlee4172great question!
Hey, I worked as a concrete QC tester for 5 years. I've never seen this rebound test before, so I looked it up real quick. Unfortunately, it is not an accepted method for strength testing. It looks could be within 25% of the real strength.
The best way, would be to drill out a 4 in diameter cylinder, or cut a 2x2x2 cube, and break it in a machine with a load cell. You probably won't want to damage your concrete though.
As for the delamination. Usually, I would see this if the finishers sprayed water on top after the concrete was mostly set up. Which is not allowed on civil projects.
I've been waiting for this video, and it's pretty much confirmed what I expected. As a Cement mason, if I poured any concrete as bad as that patio I'd ripe it out and replace it at my expense. As you said, these were experiments and the information is great! Honestly, I expected the compressive strength to be decent. But low compressive strength isn't the problem with dry-pours, it's the inconsistency throughout the slab.
The delamination is a sign of some serious problems, specifically uneven hydration. Some parts were too wet (such as the top and edges, making them brittle and weak), some were just right, and some were too dry (such as the center, making it crumbly and prone to fracturing). The cracks on the edge are likely just ordinary concrete cracking that found a perfect fault line for a particularly nasty crack. The top and edges will get too much hydration in a dry pour, but the concrete immediately underneath them will be much better hydrated. The middle is underhydrated, meaning that well-cured corner will crack at the path of least resistance (the comparatively weak middle), leading to a complete break instead of a hairline crack. The unpredictability of dry-pours isn't a bug, it's a feature. If it's showing that much wear after ONE YEAR, I REALLY want to see what it looks like after two.
As for the compressive strength, the only way to get an accurate test is to test a cylinder to failure. One way you could do that (roughly) would be to drill some core samples, stack them on top of each other, and test them to failure under a hydraulic press. It's still likely to have some decent strength, but that's not surprising. For example, layering beach sand between 1 foot by 1 foot sheets of window screen leads to a cube of sand that can hold up a car. It's called engineered earth. It's used for freeway ramps. Engineered earth will also have solid compressive strength, but it's not going to replace a home's foundation. Concrete will crack, but that shouldn't lead to any delamination or spalling. I've ground floors that looked crack free only to reveal a vast spiderweb hidden just underneath, but it was still cohesive. I'd struggle to fit the head of a needle into any of those cracks. The dry-poured slabs on the other hand look like they're struggling to hold themselves together.
The difference between a dry pour and wet-poured concrete is the life-span, and I suspect even a good dry-pour will struggle to survive past 5 years.
Have you seen the video with the 86 year-old man mixing concrete quickly using only a tarp? The technique was amazing and easy. You should look it up... very impressive.
Do a video for it, many will watch.
It is interesting to see the resulting psi on those dry pours. By your own words the unpredictability of the final appearance would be the exact reason I would never do a dry pour. Everyone has their own preference on aesthetics but I look at it from a standpoint that if you already paid for the concrete mix it proper and get a predictable result. I know some people love Jackson Pollock artwork but I don't want my concrete projects ending up like that. 🤣😂🤣
Good on you for doing the testing because it seems everyone else who promotes a dry pour never comes back later to show any real world updates.
Funny all of these imperfect surface issues in appearance..... I see in commercial wet concrete pours ... especially on side walks at new truck stops. Less than a year old .... lots of "deamination " and cracked broken corners
@@tupawskbearfuzzyears1870, I would say you may have seen a couple, but let's not exaggerate. 😕
Love the fact that you went through all the different dry pours and tests.
I was thinking, dry pour a base, leave 1/2 inch at the top of the form, then finish the job with a traditional mixture, for the remainder of the project. If cement adheres to older cement, this method might prove to be a solution for the cracking and flaking.
For the difference of 100 dollars for a mixer rental mixing the concrete is just the way tk do it. Unless you're looking to remove the patio within a certain time frame. Concrete was designed to be mixed and the negatives of not mixing are huge. Less PSI, the concrete doesn't gain strength over time when it's dry poured, it doesn't bond to the rebar if yoire using it which means that's causing damage over time not reinforcing it. There are many many more reasons to mix it and not dry pour it. Even in controlled environments where the concrete is dry poured then maintained with constant moisture for days it has these same downfalls.
If you're concerned about pouring a large concrete pad, break it down into smaller sections. Concrete needs relief points, those lines in the sidewalks, and those can be done many ways, one of which is pouring in sections
@@VeggiesOutFront
Agree 100%. The instructions are clearly marked on the bag. Deviating from the directions are problematic. I've never done a "dry pour", and I never will.
I Like the weather look as well. For sure going to use the dry method on a few projects around the house. Thanks for sharing.
The weather looks may continue to a point that it's not a good look.
Michael rocks the build!!!
Thank you. I enjoy your videos. I learn a lot.
Very interesting update on those dry pours Michael! 👍👍
Thanks for the update.
New Video 💡 : I have been building an off grid cabin & found secure set expanding foam for setting fence posts. (My back is loving NOT dragging heavy bags of concrete). The product website states that normal concrete has a 6,000 psi after 30 days and their foam has a 10,000 psi after 30 minutes. I don’t think my posts will ever move! It would be a very cool thing to check with your new toy. I love concrete but this stuff is only slightly more expensive (actually may be a bit less $ if you buy in bulk) and as we get older, those bags just keep getting heavier 😂. If this stuff is all it says, why aren’t we using it for foundations, etc? You have so much experience with concrete, I would love to see your input on this stuff! ♥️🕊
Good morning excellent thank you .
I dry poured a patio section in April because of your videos. Thanks for all the help and follow up.
Thanks for the update on that dry pour. Not that I use it but worth seeing the results after a years to see if worth wild. Thanks bud
great follow up video!
ohhh so strong Michael! 💪💪
The patio still looks great!
It would seem as if the dry pours that remained in contact with the ground, and therefore soaked up more water, where stronger. So I wonder if that would be an additional variable to consider.
This is really good to know. I stayed to watch the math makes a good argument for dry pour. I have a chicken house I plan on cleaning out with drain lines so every so. Often I clean the floors and hide it out. Thanks for the exoeriment
Maybe a good project to try out -
Make a 2'x2' form, fill it 75% dry concrete, mist it really well, add some type of metal reinforcement and then fill the remaining 25% with wet concrete which will allow you to finish it off nicely and prevent top layer separation.
I would watch that video.
👍
Dry pour looks like a great alternative if you like spalling....
Good for small projects
I was waiting for a test like this.
Looks great. I like the "decayed" look too, especially in older-home landscapes. I'd love to see you try some "Portland cement paint" and coat some concrete areas with that. Maybe it will help fill those peeling areas and cracks.
Love your videos .
The top chipping off the concrete is caused by the inside of the concrete drying slower than the top. This is why people use spray on cure or do a wet cure. It essentially slows the curing process on the surface so the concrete dries more evenly. Since a dry pour doesn’t have the water evenly distributed through the concrete it isn’t activating the lye equally and that’s what’s causing most of these problems.
I think the reason you get the flaky surface on the concrete dry poor is because of the initial misting before soaking. I’m curious if that would still happen if you did an extended initial misting that really really saturated the top layer so that the thickness was closer to a quarter of an inch or even half inch instead of a 16th or an 8th of an inch.
You should rock glue the stones in place. The patio looks great!
not sure if this will help or hurt but i live in florida and there is a road from naples fl. to ft. lauderdale called alligator alley and when it was built back in the early 60s all the bridges and there were many!! had bagged sakcrete used at the ends of each . they were laid att approx. 45deree angle up on the dirt . they were still there in the 70s when I75 replaced them .!!!!!
They lasted better than the road did, that's for sure. You would think with no frost heave or freeze cycles the roads would be better here, but nope. Cape Coral especially, the roads here are trash for how much they tax us here.
It would be interesting to see what the results would be for a dry pour done in the desert.
As a professional user of the rebound hammer, you did pretty well, but you didn't keep it perfectly at 90° at least on the first one. It probably wouldn't affect the results much. Great job!!!
Thank you so much! That is helpful! I was worried that I was going to get ripped apart for that one haha
QUESTION???? What are the results on the the one that are delaminating?? Is there a possibility that the one you tested in the middle was able to get more water so the outside ones may be lower?? Just wondering I love doing these types of tests so I would have don’t multiple tests around the patio “slab”
Most likely he over watered the delaminated ones
PSI strength will depend on the concrete mix that you used, do you remember what you used? That would tell us more about what the manufacture expected it to be in normal use as opposed to dry pour.
Looking at the video, it was the Quickcrete yellow/orange bag, which the bag states that it should be 4000psi
Great vid bro
@MichaelBuilds 11:00 link above not showing up. Also big thanks for the update
Did I miss the video on the pergola setup?
Curious to know brand/model and how holding up?
Did you bolt pergola to base and if so, how holding up?
Can you show how to do a round garden stone with military logos
I need to fill in a large area that had large raised planters for40 years , and had to be torn down because they were no longer structurally sound, aggregate cement was poured around that. I’ve pondered anything from brick pavers to artificial turf. I wonder if this is the solution? And what would be the best way to do a dry poor inset the empty space?
I wonder if you can do stamped concrete dry poor?
May test a wet pour with this gadget? Also test a few slabs?
How about testing the worst section not the best in the gazebo?
CORRECTION for those who think they learned something physics-y. A "Newton" measures force, not pressure. That device he's using measures Newtons per square millimeter, not Newtons. It's right at the top of the chart he shows. 1 Newton per square millimeter ~= 145 PSI. Those extra digits past the decimal point given for the conversion don't mean much IF... IF... IF... the way that device obtains its result is affected by the local value of gravitational acceleration (e.g. ball drop), which can be +/- 0.2 PS1 between Seattle and Los Angeles due to the "centrifugal" affect of the rotation of the earth. (This is why you were tortured with "significant figures" in science class).
Seems like the dry pours that were in direct contact with the ground did better.
That's actually a great observation. I think if the ground below the dirt is wet then that's the best because the concrete can pull the moisture up.
I had concrete steps in a house poured the "right way" and the top started flaking off too, so Concrete is never 100% consistent regardless on how you pour it.
What was the bag rated for? 5k? Or 4k? Sidewalks are 3-4k so. That's great.
Could see a wider gap over time. If you look at some of the compressive strength charts 5-10 years out, those get stronger.
Awesome vid, so interesting.
I have been doing a bunch of dry pours using 24/6 rapid set. Says 6000 psi on the bag. I wonder how much a difference this makes as opposed to the normal concrete mix.
I think you used the 24/6 rapid set for one of your dry pours, but I cant remember which one.
You could always do a couple of dry pour cylinders and after 28 days or a year, take them to a testing lab then you'd know for sure
I suspect the peeling is related to hot temperatures water tries to escape the crust if it’s hot . At least that’s what happened to mine.
Heeeeyyyy Michael!!!! 😃
What if you sealed the dry poured concrete? AR500 by Armor
It's already been a year? Dang... Let's get it on... In a pinch but, traditional is better. Thanks for the update.
I know @Micheal Builds did this as dry pour for a reason, but imagine if he did it the right way. This patio would look so good.
What is the right way?
Next test, use a hydraulic shop press.
I can imagine dry pour being great for a walkway like on the side of a house, where people don't care how it looks as much. I think the compression test might be flawed, but I'm not professional. The only reason I say that is because you're testing the top of the dry pour and that's the main part that got water. As we saw in some other dry pour videos, the bottom doesn't get nearly as saturated and I don't know if the improper saturation makes it worse or not.
I worry about the methodology here. AFAIK that type of tester can only measure the compressive strength of a shallow layer. If the top layer is fully cured (exposed to enough moisture to do that) but an inch below the surface is still dry, all you have is a hard layer on top of basically dust. It might be fine for patio furniture but if you used this method on anything that actually requires a certain thickness (e.g. 4", 6", a footing, etc...) you could have a dangerously weak core under a thin, hard shell on top. It would be interesting to see you use this same tool on a test pour or two, say 1'x1'x4" and maybe 1'x1'x6", then cut the test piece with a disc and test the sides/bottom.
I would bet if you tested enough thicknesses, you'd probably find some maximum that can be used as a rule of thumb between "just DYI it with a dry pour" (pavers) and "that really does need a wet mix" (garage slab). If the center isn't going to cure past, say, 3" thickness, you might as well just lay down a (cheaper) bed of sand and do a thinner layer of concrete over that...
Thanks for revisiting these dry pours. I think the delamination is a result of your dry pour technique. I went back to watch the video of you dry pouring the blocks, I think when you misted, you put way too much water on the concrete, and the after the mistings, it's supposed to be a shower not just pouring out of the hose. Also, I don't think you watered them enough, supposed to be 2 showers per inch, 1 every hour. So 8 showers since you have a 4" thick block, 8 hours of showering.
Ahh, i didnt get a link to the original patio pour...i know i watched it, but it was a year ago...
Dry pour should be strictly used for post setting that does not require major tensile strength. Other than that it is a waste and a matter of time until it will require to be torn up
Looking forward to a resurfacing/repair video ... 😅
Does dry pour really save time or effort? Why the trend to make it work other than content?
So it has been 39 months since you quit your job and become a full time UA-camr. In that time, I have seen, I believe, 68 videos. Are you still happy? Does it pay enough with putting out almost 2 videos a month? I know it helped that you had a decently large audience before quiting. Any advice for someone considering the same?
OK ok ok So, what would happen if you did a dry pour in lifts. Like 2 inch lifts minutes a parts. So just my brain rattling around. Keep up the great work.
Newtons can't be directly converted to PSI. Newtons are equivalent to pounds. You want Pascals.
Good catch. I checked his chart, and it says N/mm^2.
@@chrisvids1820 Megapascals, then.
Your conversion of Newton to PSI is dubious. PSI essentially maps to Newton/unit area. So, in order to do this conversion, you need to have some kind of surface area term you divide by. You cant just say 1 Newton = this many PSI because these are not the same kind of quantity. Namely, a Newton is not a unit of pressure, but a N/m^2 is. Can you give more details?
I build houses and dry poor all my footers
N and Nm make sense to people who work on German cars
No, it makes sense to most of the world that uses the metric system. I grew up educated in and using both metric and imperial, no issue.
@@turkeytrac1 - MURICA!
Sorry, had to.
I mean, my take-away from this video is that dry pouring can work, but it's unreliable, and typically results in much weaker (and uglier) results, so, outside of some niche circumstances, you should basically always do a traditional pour.
8:00 bro what, it looks just like the gazebo! Just as bad
What sucks about this is that your patio was set up perfectly to just do small mixed batches.
You could have shown people the proper way to do a project out of their league. It should be easy to break up and remove in a few years
You're gonna need to buy more land to keep dry pouring things.
❤😊❤
I don't get the fascination with Dry pour it is 1/4 as strong and no easier than traditional.
My wife dry poured a dog pad. I’d say it’s easier if she could do it by herself.
So, the conclusion is the same one I came to. Tricks on the internet aren't proof. It was started by DIYers trying to trick people to subscribe, to make money. I was a contractor and I'm a UA-cam influencer- it's bogus.
90 delaminated called scaling
Dry pour is just unpredictable.. inconsistent. As shown rapidly by the surface defects in the patio.
Sure. you can get places that work well. But you get too much that goes wrong.
Just too easy to use a Harbor Freight mixer and do it right.
Nah…don’t do it yall.
Harder but worth doing the mixing.
These numbers are garbage without correlation to core sample test. It is extremely important to note that the hammer must not be regarded as a substitute for standard compression tests but rather as a method for determining the uniformity of concrete in the structures, comparing one concrete against another, and reducing the number of core samples. You also have too much scatter in your data and thus the data should be collected again. Additionally, a newton is a unit of force and not pressure, so you need an area to be able to convert to PSI (Pounds per Sqaure Inch). I assume your measurements are Newton per sqaure millimeter, but not sure since you didn't mention it.
Dry pour is always bad. Always. Every single strength test fails. Don’t do it
It also looks like shit and doesn't have any customization options like stamping or any other options.
@@brandonm9359 LOL 🤣🤣 yeah, that patio looks horrible! 🤦
There is a concrete guy who does more thorough testing and it’s nowhere near the strength of poured crete never mind the looks. For those saying it looks “good” it’s only a year old concrete lasts for (about) 100 years and I can imagine what it’ll look like after (only) 20 years when failing when (in theory) it’s only a baby
Duuuuuuuuude.
A Ryobi pressure washer??, is really just a strong-stream garden-hose brah 🤦♂️
Lol
2300psi works home gamers lol (at least it’s not the EZ Clean. That thankfully doesn’t take up too much room in the trash can)
Mine works fine for what I use it for.
@@antiisocial - same
This is the guy where the face does not match the voice, not even close
Please lower the volume of the music!!!
No issue on my end.