Soil Cement Volume Needed
Soil Cement Volume Needed
(OP)
Need some help please....
We have a 122 foot diameter structure with a 5 foot removal of existing soil under the proposed slab ( ox ). We are planning to remove 1/2 the diameter for the full 5 foot depth, stockpile the material, and then process and compact the sub grade. We need to add 3% cement back to the soil and plan on placing fill back in 1 foot +- lifts to the OX'd area and re compact the 5 feet. The 3% is based on dry weight with the soil at 98 lb ft3. My question is the formula needed to determine how much cement to add to the 5 feet of material to achieve 3 % by weight. I then figured to divide that weight by 5 to achieve the required amount of cement for each lift ( 1' ) ? Can someone please help me break this down ?
Thanks for the help ...
We have a 122 foot diameter structure with a 5 foot removal of existing soil under the proposed slab ( ox ). We are planning to remove 1/2 the diameter for the full 5 foot depth, stockpile the material, and then process and compact the sub grade. We need to add 3% cement back to the soil and plan on placing fill back in 1 foot +- lifts to the OX'd area and re compact the 5 feet. The 3% is based on dry weight with the soil at 98 lb ft3. My question is the formula needed to determine how much cement to add to the 5 feet of material to achieve 3 % by weight. I then figured to divide that weight by 5 to achieve the required amount of cement for each lift ( 1' ) ? Can someone please help me break this down ?
Thanks for the help ...





RE: Soil Cement Volume Needed
That should be about 17,184 lb of cement per lift or about 182 standard sacks of cement (94 lb/sack).
RE: Soil Cement Volume Needed
RE: Soil Cement Volume Needed
RE: Soil Cement Volume Needed
Thanks for the response.
If you get a chance , can you please explain what the /4)/2) portion of the formula is ?
I'm getting the pi * d ^ 2 portion, as well as * 0.03 * the dry weight of the soil.
Are you saying then that the 17,000 + lbs represent ( 1 ) one foot lift for 5 vertical feet of fill over 1/2 the tank ?
If this is the case, we are looking at approx 1820 94 lb standard sacks for the total job ? As we will do the same removal and re compact for the other 1/2 of the tank bottom.
"((pi*d^2)/4)/2)*0.03*98=weight of cement for 1 foot lift "
Thanks again sir. Really appreciate the help .
peace....
RE: Soil Cement Volume Needed
Now the challenge will be to get that cement properly mixed into each lift for proper uniformity and the compaction :)
Thanks again for the help guys.
peace...
RE: Soil Cement Volume Needed
If you don't do that, you'll be looking at trying to uniformly spread cement to a depth of less than 1/4-inch over the area of each lift, then mixing that into the existing soil for each lift. Generally we put a limit of 2 hours from time of first introduction of moisture into the cement to final compaction for such mixing and compacting operations. That works ok for road work, but for confined area, non-linear sections, it can be very difficult.
With a pugmill mixer, you can work at whatever pace you want and you'll have ready supply of material there that is fresh and has not started to hydrate.
Check with local aggregate or asphalt suppliers. They might have a portable pugmill mixer they will rent or will do the job for you.
good luck.
RE: Soil Cement Volume Needed
RE: Soil Cement Volume Needed
RE: Soil Cement Volume Needed