Fills shall be considered as satisfactory bearing material of the applicable class when placed in accordance with the following procedures and subject to the special inspection provisions of Chapter 17:
- Area to be filled shall be stripped of all organic materials, rubbish and debris.
- Fill shall not be placed when frozen or on frozen or saturated subgrade.
- The special inspection agency shall approve the subgrade prior to fill placement.
- Fill material shall consist of gravel, crushed rock, recycled concrete aggregate, well-graded sand or a mixture of these, or equivalent materials with a maximum particle size of 3 inches (76.2 mm ) and a maximum of 10 percent passing the #200 sieve.
- Fill shall be placed and compacted in lifts, not exceeding 12 inches (305 mm), at its optimum moisture content, plus or minus 2 percent, and to not less than a density of 95 percent of the optimum density as determined by ASTM D 1557.
- Fill density shall be verified by in-place tests made on each lift.
Provided the capacity of the underlying soil is not exceeded, the allowable bearing pressure of controlled fill shall be limited to:
- 6 tons per square foot (766 kPa) for gravel and crushed rock.
- 3 tons per square foot (383 kPa) for recycled concrete aggregate and well-graded sand.