I am building a pit to hold some huge, uncommon, expensive machinary that is very interesting to discuss but of little importance to my question, so I will omit that info. Pit dimensions:
12-20 ft deep
50’ x 32’ L x W
wall thickness 16"
Slab depth 2’9"
The project is located in the East bay area and has a water table depth of 40’ according to the soils report. We are soil-nailing for shoring purposes and shotcrete-ing the walls to finished thickness. We would like to do this in one pass but will not be able to waterproof with traditional polyurethane membranes due to the soil nails. The only water mitigation will be a corrugated backing placed behing the shotcrete down full depth into a 12" layer of base rock.
My question is does anyone have any thoughts about how risky this would be to simply not waterproof other than the backing. And, does anyone know how well sodium bentonite or Integral crystalline waterproofing methods work?