Evaluation of Vertical Bearing Capacity of Super-Long Bored Single Pile by the Pile Head Settlement in Loess

The load transfer mechanism and bearing characteristics of super-long bored single pile are addressed in this paper. A tri-linear model and a bi-linear model are adopted for the toe and the shaft resistance, respectively. An analytical solution to predict the vertical bearing capacity is obtained, taking into account various bearing status of the soil or bedrock around the pile shaft and under the pile toe. The influence of different soil strata, nonlinear behavior of the surrounding soil or bedrock, and the sediment under the pile toe are considered as well in the present solution. An idea to predict or control the axial bearing capacity of large-diameter and super-long bored piles by the allowable pile head settlement is proposed herein. The loading capacity by design method in this article is more bigger than standard method, find out some potential bearing capacity of pile foundation, make the pile foundation bearing more coordinate with pile deformed, and more reasonable in theory than standard method, so the calculate method in this article can offer reference to engineering practice.