碎石桩复合地基非线性固结分析

Nonlinear consolidation analysis of stone column composite ground

针对非线性偏微分固结方程难以直接求得解析解答的问题,采用对固结时间离散化的方法编制固结计算程序,在每个计算时间段内假设桩周土土体及碎石桩参数为常数,建立固结控制方程并求解。根据上一时间段的计算结果确定下一时间段的计算参数和初始条件,实现了同时考虑碎石桩和软土非线性特征的复合地基固结计算。在此基础上,分析了复合地基的固结性状,得出碎石桩复合地基随着Cc/Ck增大其固结速率变慢的结论。

It is difficult to obtain the analytical solution of a nonlinear consolidation partial differential equation. In order to solve this problem, the consolidation time is segmented into small intervals and the parameters of soft soil and stone columns are assumed to be constants at any time interval. Then, the governing consolidation equation of the stone column composite foundation is built and solved at each time interval. The calculation parameters and initial conditions of the computing unit can be determined by the calculation results of a previous time interval. Finally, consolidation calculation is conducted for the composite ground, with consideration of the nonlinear characteristics of the stone column and soft soil. On this basis, the nonlinear consolidation properties of composite ground are analyzed. The results show that the consolidation rate of the stone column composite ground decreases with the increase of Cc / Ck .