复合地基调平前后在水平力及偏心荷载下性状分析

摘要

The MIDAS-GTS software is used to simulate six models of composite foundation.Firstly,under the condition of the same pile volume and vertical uniform load,the length of group pile is adjusted to make sure that the base is uniformly forced and the base is balanced.The optimum model of adjusting level is chosen from four kinds of balanced model.Secondly,the horizontal force and equivalent force of eccentric load on the raft are computed by using this optimum model.Simultaneously,the horizontal force and force of eccentric load are also computed using the base model with imbalance.Finally,compared with the differential settlement,the bending moment and the axial force of pile groups under basis balance and basis imbalance,this study obtains the stress variation law of raft and pile with rigid pile composite foundation.Moreover,the above studies provide a useful reference for the optimization research of rigid pile composite foundation with variable stiffness.%采用 MIDAS-GTS 有限元软件，模拟了复合地基的6种模型。首先保证刚性桩总体积相同，在竖向均布荷载下，通过调整群桩桩长使其基础整体受力均匀后调平基础，对比模型的4种调平方案，选出最佳的调平模型；然后采用群桩的最佳调平模型在筏板上进行水平力及偏心荷载下的等效受力计算，同时采用基础调平前（等刚度布桩）的计算模型在水平力及偏心荷载下进行受力计算；最后对基础调平前后的差异沉降、弯矩大小与群桩的轴力、弯矩进行了对比分析，得出刚性桩复合地基变刚度调平前后筏板与群桩的受力变化规律，为优化复合地基变刚度桩的研究工作性状提供了参考。