水平荷载作用下PCC桩复合地基工作性状

利用河海大学岩土所自行研制开发的大型试验模型槽进行PCC桩水平承载足尺试验,实测得到了水平荷载作用下桩身弯矩分布。利用三维弹塑性有限元方法,研究了PCC单桩与等截面实心圆桩、PCC桩复合地基与等截面实心圆桩复合地基在水平荷载作用下的工作性状,对其桩身弯矩和水平位移的分布规律进行了比较,分析了竖向荷载、褥垫层厚度、基础埋深和置换率对PCC桩复合地基桩身性状的影响。研究表明,PCC桩复合地基在水平荷载作用下,随着竖向荷载、褥垫层厚度、基础埋深和置换率的增加,其桩身弯矩和水平位移随之减小。因此,在PCC桩复合地基设计时可以通过适度调整这些影响参数来减小水平荷载作用下的桩身弯矩和水平位移,确保桩身的安全。

Behavior of PCC pile composite foundation under lateral load

In order to obtain distribution of bending moment along PCC pile under lateral load, full-scale model tests were carried out using large test tank developed by Hohai University. The three-dimensional elastoplastic finite element method was used to study the behavior of PCC pile and homalographic solid circular pile as well as PCC pile composite foundation and homalographic solid circular pile composite foundation under lateral load. The effects of different design parameters of PCC pile composite foundation on distribution of bending moment and deflection along pile were obtained. The study results show that the internal forces and deflection along pile decrease with the increment of vertical load, thickness of cushion, depth of foundation, and replacement ratio. It is concluded that the internal forces of pile can be reduced to ensure the safety of the pile by the appropriate adjustment of the main design parameters in the design of PCC pile composite foundation.