摩擦型长桩承载力计算的探讨

从分析摩擦型长桩的荷载传递机理出发, 指出了目前摩擦型长桩承载力计算公式的不足。按照荷载传递实际性状, 分析了桩-土相对位移与超长桩的承载性状之间的关系, 以桩土极限相对位移为界限, 将桩分为破坏滑移段L_z和非滑移段(L-L_z), 且探讨了Lz的计算。在非滑移段利用桩土接触面双曲线模型模拟桩侧摩阻力与桩土相对位移的关系, 得到非滑移段的桩侧摩阻力公式, 最后推导出了摩擦型长桩承载力计算总公式。实例表明, 该计算公式具有一定的理论及工程意义。

Discussion on the Bearing Capacity of the Frictional Long-pile

The limitation of the current calculating formula is pointed out based on the analysis of the loading mechanism of the frictional long-pile.The relationship between the bearing capacity of super-long pile and the pile-soil relative displacement is analyzed.Meanwhile,the frictional long-pile is divided into two parts based on the pile-soil limiting relative displacement,namely,slip part L_z and non-slip part(L-L_z),and the calculation of L_z is discussed as well.The formula for calculating the frictional force of the non-slip part is deduced by simulating the relationship between the frictional force of the pile and the pile-soil relative displacement by using the hyperbolic model of the pile-soil contact surface.An integrated formula for calculating the frictional long-pile is obtained.The example given in this paper shows that the formula is of the oretical and engineering significance.