Driven Piles in Clay (II) Consolidation after Driving

摘要

Numerical and analytical techniques are used to investigate the effective stress changes with time, due to the dissipation of pore pressures in the soil around a driven pile. Soil consolidation is represented by a work-hardening elasto-plastic soil model which has the unique feature of allowing the strength of the soil to change as the water content changes. The intrinsic soil strength can be calculated at any stage during consolidation. The long term shaft capacity of a driven pile may be estimated from the final effective stress state and instrinsic strength of the soil adjacent to the pile. A parametic study is made of the effect of the past consolidation after installation of the pile. A method is described whereby the model of pile installation and subsequent consolidation may be extended to clays which are sensitive. The method is used to predict changes in the strength and water content of soil adjacent to a driven pile.