Performance of piles cast in predrilled holes and consolidated masses during slump-type settlements of soils surrounding them due to their own weight

Conclusions

1. Considerable additional loads are transmitted during slump-type settlement of surrounding undisturbed soils due to their own weight as a result of impendence and the development of negative friction along the lateral surface on piles that are cast in predrilled holes. In this case, the tangential stresses developed over the lateral surfaces of a pile reach 0.043 MPa.

2. As a result of interaction between consolidated masses and undisturbed loess soil surrounding them, impendence of the loess soil on the consolidated masses takes place during slump-type settlement of the former. As a result of this, the undisturbed loess soil is partially unloaded, its slump-type settlement is reduced, and the consolidated masses receive an additional loading, which results in compression of the lower portion of the consolidated mass and underlying layers.

3. The bearing capacity of piles and consolidated masses at sites having soil conditions classed as type II with respect to tendency to slump-type settlement should be determined with consideration given to the impendence of the surrounding undisturbed soils on them during slump-type settlement of the latter due to their own weight, which results in the development of negative-friction forces along the lateral surface of the pile and consolidated masses.