考虑时效作用的桩基承载力计算方法研究

Research on calculating pile's bearing capacity considering time-effect combining

采用空间轴对称固结有限元结合修正剑桥模型,用柱形孔扩张对沉桩过程进行模拟,求出不同时期桩周土中的应力,从而得到不同间歇期桩侧的最大摩擦力。应用荷载传递法对桩基承载力进行计算,结合桩周土体剪切强度、应力状态的变化,得到了考虑时效影响的桩基承载力的计算方法。实例计算表明,结果较合理。

The cylindrical expansion combining with spatial axisymmetrical consolidation finite element method and modified Cam-clay model, is adopted to simulate pile driving. Stresses around a pile at vavious time can be calculated and then the maximum frictional force of pile-soil interface at various time can be obtained. The load transfer method is adopted to compute pile抯 bearing capacity. Considering the change of mechanical property and stress state of soil adjacent pile, a method of calculating pile抯 bearing capacity considering time-effect is gained and an example shows it is rational.