Me...My hole...and the mystically selfcompactable #57 Stone
Me...My hole...and the mystically selfcompactable #57 Stone
(OP)
We have begun excavation on my house where I've taken on the pleasure of being the GC. I had a large Sweetgum tree removed which was in line with the front of the house. After laying out the footings, the hole where the tree was is exactly where the corner of my foots for the grarage wall. My excavator says we can clean up the soil (to an undesturbed level) and fill to grade with #57 stone and pour the footings across that (hole is 6' wide and 3' deep). Code says undisturbed soil or engineerd fill. Is #57 Stone an "engineered fill".





RE: Me...My hole...and the mystically selfcompactable #57 Stone
#57 stone has a large void volume, which can be filled with surrounding soil raveling into those voids by groundwater movement and by surface water infiltration.
Use select structural fill material and compact it in accordance with acceptable compaction standards.
RE: Me...My hole...and the mystically selfcompactable #57 Stone
RE: Me...My hole...and the mystically selfcompactable #57 Stone
Your state DOT will have specs for select structural fill along with compaction requirements. Most, if not all, DOT's post their specs on line.
RE: Me...My hole...and the mystically selfcompactable #57 Stone
RE: Me...My hole...and the mystically selfcompactable #57 Stone
Engineered fill would be soil material that is free of deleterious materials, construction debris, organic material, or any rock material greater than 1" in size. The material should contain no more than 10% fines (clay, silt or a combination) and should be classified as GW, SP, SP-SM or SP-SC.
The material should be placed in lifts not to exceed 8" in thickness and compacted to achieve an in-place density of not less than 95% of the modified Proctor maximum dry density. This is similar to what your County Inspector told you...he's right.
Fill material is usually available in most any area...call around. You might be able to get enough for this application from your own site by re-grading or from your footing excavation in other areas.
RE: Me...My hole...and the mystically selfcompactable #57 Stone
I've got plenty of soil from the excavation. The house has a full basement with walkout. Soil, I am told, is excellent 1/8" and less gravel with not much sand. We have been able to drive a 50,000lbs excavator on it with the soil fully saturated (which is my other problem we are working but that is easier to solve) with no visible trace of disturbance from the tracks. So soil is possible SP.
RE: Me...My hole...and the mystically selfcompactable #57 Stone
Your soil could be a GP or SP...in either case, sounds fairly good. From your soil description and the fact that you have a basement, I assume you are in the piedmont area of SC, not the coastal plains. Typically good foundation material when compacted.
RE: Me...My hole...and the mystically selfcompactable #57 Stone
I think my solution is a s follows: I'm moving the house back 5'. Filling the bottom of the hole with gravel and a perforated pipe connected to the french drain and compacting local seleced soil in 8" lifts to stablize the sides. In the footings along side the hole I'm going to have them put #4 rebar lateral across the footings. Should be best all around...exect for my budget!
RE: Me...My hole...and the mystically selfcompactable #57 Stone
RE: Me...My hole...and the mystically selfcompactable #57 Stone
RE: Me...My hole...and the mystically selfcompactable #57 Stone
RE: Me...My hole...and the mystically selfcompactable #57 Stone