水平荷载作用下分层土体群桩复合地基中圆桩与方桩的变形性状

为了在复合地基理论与工程应用中合理地选用桩截面，分别对分层土体群桩复合地基中的圆截面桩与方截面桩在水平荷载作用下的变形性状进行了有限单元法的三维弹性分析，得到了圆截面桩与方截面桩在不同土层材料特性下出现最大应变的位置及其轴向应变性状，以及桩体的断桩点随土体分层状况改变而变化的规律。对计算结果的比较表明，圆截面桩的最大应变均比方截面桩的最大应变大，从而判断出在桩体横截面面积相等的条件下圆截面桩承载力比方截面桩承载力小许多。

Deformation Property of Circular Pile and Square Pile in Pile Group Composite Foundation Under Horizontal Load in Multi-layered Soil

To choose cross-section of pile reasonably in the theory and engineering appliance of composite foundation, finite element method was adopted to analyze respectively, in a 3-D elastic analysis, the deformation properties of circular cross-section pile and square cross-section pile in pile group of composite foundation under horizontal load, when different multi-layered soil conditions were considered. The respective property of axial strain for circular cross-section pile and square cross-section pile at the location where maximal strain occurs under different material properties of layered soil was obtained. The variation law for the fracture point of pile which will most possibly occur along with the change of different soil layer conditions was also obtained. Then through comparing the results, maximal strain of circular cross-section pile is higher than corresponding square cross-section pile, it is concluded that the load bearing capacity of circular cross-section pile is much smaller than corresponding square cross-section pile under the condition that both of them have identical cross-section area.