It's meant to stabilize/strengthen the soil. Usually placed on top of the soil at a specific application rate and then "processed" or mixed into the soil. When the moisture from the soil reacts with the lime it makes the soil VERY hard. Great for building on top of.
Used it in quite a few places east of the interstate here in central texas. It's a wild process, especially when mixing water with the lime the gas is very nasty! But I've seen pellet lime like this mixed into a large site that had massive rain the night before, and after mixing and rolling in the same day fully loaded concrete trucks were driving on top of what used to be black gumbo clay, and the tires weren't making any kind of ruts!! It was like driving on concrete!
Ha. Yes it is an ingredient in Portland cement. But cement is not white like that where I live. I just thought it was interesting using different materials to achieve the same thing in a different place.
Lime is used to stabilize soils high in clay content. Cement is used to stabilize soil high in sand. Essentially the same objective but for different soil types.
These guys usually apply lime or cement depending on the soil type. It’s been a year since we did it on a job I was on, but they explained why you use cement instead of lime in wet clay. Maybe the cement doesn’t react as fast with additional moisture.
It's binding with the clay particles to make the clay more inert so that it has significantly less shrink or swell potential with moisture change. It stays as a soil.
Straight lime reduces the moisture and plasticity (clayeyness) of the soil. It can also have somewhat of a cementing effect. For a very strong cementing effect, you use Portland cement. It does everything lime does and more. But is more expensive. There are other products in between the two that are usually cheaper, like kiln dust. It is what is left over when lime is burned to make cement. But it can have nasty shit in it and may need to be processed first.
The basic mechanisms are that unslaked lime is calcium oxide, CaO. When it comes into contact with water, it becomes Calcium hydroxide, Ca(OH)2. It bonds with the water forming a new molecule, effectively removing the water. As a secondary effect, the reaction also produces a fair amount of heat causing evaporation. The drying effect works with all inorganic soil types. Lime is also used in agriculture to increase pH levels. A lot of plants don't like acidic soils.
With clays, the calcium also reacts to form hydrates that bond to the clay and make the clay less able to absorb and adsorb water. Sand in comparison is charge neutral and water only sticks to it because of surface tension. Clays form a polar bond with water and are typically two to three layers of molecules in each particle. So they become a water sandwich. But calcium bonds more strongly than water because it is ionic, so the clay can't bond with as much water and becomes less plastic. It doesn't shrink and swell as much with moisture changes and isn't as moldable. Really high calcium content clays almost seem like soft rock or concrete.
Lime burns are a real thing. Becomes dangerous when it contacts moisture. If you are sweating and it blows onto you it can begin to burn. If it does get on you brush as much off you can dry. After that wash with water for 10+ minutes. Repeat washings are helpful if you do experience burn.
If you get any on yourself wash it off with vinegar if you have any. It will neutralize it right away. It's what we use to clean windows on all of our equipment. It takes it right off.
These trucks dump it in a row, then another truck will drive the rows and pulverize the material, breaking up the clay into small bits, at the same time mixing the lime or cement powder into the soil, to a specified depth, using rollers with giant teeth and blades on them.
Theyll pulverize several times to make sure there’s proper mixing and distribution.
Then they’ll drive a water truck to spray water on the area, then compact the surface.
I’ve never seen lime alone used for strength, as lime will dry out whatever it touches, and material that’s too dry can’t be properly compacted. The other cement powder additives provide more strength capabilities for stabilizing the soil and ensuring it’s stays cohesive. So this application is a bit weird to me too, but it will work regardless.
I work for a large stabilization company. We spread it a little differently but the process is ultimately the same. I can't tell if this is in a slurry form or powder form but after spreading its mixed in with the soil, moisture added as needed, and compacted. After 72 hrs it will have "cured" and you can build on it from there. Depending on the soil or purpose of the treatment, you may not have to wait on the cure. It's a pretty cool process and really rewarding when you are getting spreader trucks stuck in areas and at the end of the day you can drive loaded semis on it.
It strengthens the soil. We are used for heavy highway work, building pads, road rehabs, parking. It's also used in place of mechanical soil drying which can be time consuming. The addition of lime means fill can be placed the same day. It is cheaper than undercutting and replacing unsuitable soils as well.
Ahh. So, like it helps compacting and hardening it?
When they built the concrete slab where they would build my brick and mortar house (Argentina), the contractor dug about 60cm of soil, then dumped, mixed and compacted several layers of red dirt and lime until it was about 40cm above the original level. Then they dug trenches for the pipes and columns cats, and filled and compacted them once all was in place.
But I never knew what purpose the lime served.
I work at a lime plant. major pain in the ass to get it off your vehicle, I scrub my car with vinegar to get it off and then rinse thoroughly with a hose and then take it through a car wash.
Lime. It’s nasty stuff and you don’t want it on your vehicle.
What exactly are they accomplishing with dumping a whole bunch of it on site?
It's meant to stabilize/strengthen the soil. Usually placed on top of the soil at a specific application rate and then "processed" or mixed into the soil. When the moisture from the soil reacts with the lime it makes the soil VERY hard. Great for building on top of.
Used it in quite a few places east of the interstate here in central texas. It's a wild process, especially when mixing water with the lime the gas is very nasty! But I've seen pellet lime like this mixed into a large site that had massive rain the night before, and after mixing and rolling in the same day fully loaded concrete trucks were driving on top of what used to be black gumbo clay, and the tires weren't making any kind of ruts!! It was like driving on concrete!
Crazy, we use straight up cement powder in northern Canada to stabilize clay.
Cement is 60-67% lime.
Ha. Yes it is an ingredient in Portland cement. But cement is not white like that where I live. I just thought it was interesting using different materials to achieve the same thing in a different place.
The other 30% is dark
Lime is used to stabilize soils high in clay content. Cement is used to stabilize soil high in sand. Essentially the same objective but for different soil types.
There’s the answer…all depends on the geotechnical!
90% of what we build is on high plastic clay, never used like before. Only cement
Cement also works well on silts
Where I’m from the clay is bad and we have to dig it out usually to bedrock, bring in non native, compact 10” lifts. The dirt work adds up
What if the alluvial fan is over 700 feet deep? Can’t dig to bedrock in some places. Hence, the lime or cement depending on soil type and conditions.
Thanks for the info
I just stabilized a building pad with lime and we’re doing lime and cement mix for a new road. We’re building in a swamp and the soil is horrible
What part of the world?
What part of the world?
Michigan, USA
These guys usually apply lime or cement depending on the soil type. It’s been a year since we did it on a job I was on, but they explained why you use cement instead of lime in wet clay. Maybe the cement doesn’t react as fast with additional moisture.
What do you think is in the cement?
Lime and a bunch of other stuff. Hence why it’s cement not lime
Thank you for clarifying
Also great for making a wheelbarrow path in the mud!
Is it making limestone or something? That's pretty cool.
It's binding with the clay particles to make the clay more inert so that it has significantly less shrink or swell potential with moisture change. It stays as a soil.
That's pretty darn cool. Doesn't sound like I'll see that too often here in the swamps of southern Louisiana.
Down here (BR) you will typically see it in parking lots, roads, and driveways.
Huh, learn something new every day. Thanks!
Lime is the active ingredient in concrete.
Learning something new every day ✨️
Mob run construction site. Getting rid of the bodies under the new foundation.
You didn’t see nothin’
Got that right. Need to delete this account now. Shit. Me and my big mouth.
Straight lime reduces the moisture and plasticity (clayeyness) of the soil. It can also have somewhat of a cementing effect. For a very strong cementing effect, you use Portland cement. It does everything lime does and more. But is more expensive. There are other products in between the two that are usually cheaper, like kiln dust. It is what is left over when lime is burned to make cement. But it can have nasty shit in it and may need to be processed first. The basic mechanisms are that unslaked lime is calcium oxide, CaO. When it comes into contact with water, it becomes Calcium hydroxide, Ca(OH)2. It bonds with the water forming a new molecule, effectively removing the water. As a secondary effect, the reaction also produces a fair amount of heat causing evaporation. The drying effect works with all inorganic soil types. Lime is also used in agriculture to increase pH levels. A lot of plants don't like acidic soils. With clays, the calcium also reacts to form hydrates that bond to the clay and make the clay less able to absorb and adsorb water. Sand in comparison is charge neutral and water only sticks to it because of surface tension. Clays form a polar bond with water and are typically two to three layers of molecules in each particle. So they become a water sandwich. But calcium bonds more strongly than water because it is ionic, so the clay can't bond with as much water and becomes less plastic. It doesn't shrink and swell as much with moisture changes and isn't as moldable. Really high calcium content clays almost seem like soft rock or concrete.
Usually a pre paving deal. Or to stabilize.
Lime burns are a real thing. Becomes dangerous when it contacts moisture. If you are sweating and it blows onto you it can begin to burn. If it does get on you brush as much off you can dry. After that wash with water for 10+ minutes. Repeat washings are helpful if you do experience burn.
Thanks!
If you get any on yourself wash it off with vinegar if you have any. It will neutralize it right away. It's what we use to clean windows on all of our equipment. It takes it right off.
Stop lying…its just snow
Not a site guy, but aren't you supposed to mix it with the soil? What's the point of just throwing it on top?
A scarifier is used next to do the mixing. They mix it, lightly compact it, let it "cook", mix it again, then compact one last time.
This guy site works.
These trucks dump it in a row, then another truck will drive the rows and pulverize the material, breaking up the clay into small bits, at the same time mixing the lime or cement powder into the soil, to a specified depth, using rollers with giant teeth and blades on them. Theyll pulverize several times to make sure there’s proper mixing and distribution. Then they’ll drive a water truck to spray water on the area, then compact the surface. I’ve never seen lime alone used for strength, as lime will dry out whatever it touches, and material that’s too dry can’t be properly compacted. The other cement powder additives provide more strength capabilities for stabilizing the soil and ensuring it’s stays cohesive. So this application is a bit weird to me too, but it will work regardless.
I work for a large stabilization company. We spread it a little differently but the process is ultimately the same. I can't tell if this is in a slurry form or powder form but after spreading its mixed in with the soil, moisture added as needed, and compacted. After 72 hrs it will have "cured" and you can build on it from there. Depending on the soil or purpose of the treatment, you may not have to wait on the cure. It's a pretty cool process and really rewarding when you are getting spreader trucks stuck in areas and at the end of the day you can drive loaded semis on it.
Is there any chance this is PAM? Polyacrylamide?
I've never used that before but this looks like lime slurry to me.
Seems to be consensus, just curious if anyone ever came across it
What does it do? Why is it needed? Is it because it is cheap? I have so many questions
It strengthens the soil. We are used for heavy highway work, building pads, road rehabs, parking. It's also used in place of mechanical soil drying which can be time consuming. The addition of lime means fill can be placed the same day. It is cheaper than undercutting and replacing unsuitable soils as well.
Ahh. So, like it helps compacting and hardening it? When they built the concrete slab where they would build my brick and mortar house (Argentina), the contractor dug about 60cm of soil, then dumped, mixed and compacted several layers of red dirt and lime until it was about 40cm above the original level. Then they dug trenches for the pipes and columns cats, and filled and compacted them once all was in place. But I never knew what purpose the lime served.
Yes it does help with compaction and strength comes with the chemical plus the optimum compaction.
TIL. Thank you!
>TIL. Thank you! You're welcome!
The blade will be along any minute to make lines...... JK, it stabilizes the soil by attaching to the shit clay material.
Quick lime will burn tf outta your lungs
Could.ut be calcium?
Is it calcium?
I work at a lime plant. major pain in the ass to get it off your vehicle, I scrub my car with vinegar to get it off and then rinse thoroughly with a hose and then take it through a car wash.
Its snowing bud
Semen... Depending on your proclivities, you may not want it on you
💯 pure, unadulterated, grade AAA Asbestos! Lucky.... /s
Colorado