密排支护桩挤土效应研究  

Study on the soil compacting effect of retaining pile while close-packing

作　　者：徐美娟[1] 郭玉君[2] 黄广龙[3] 

机构地区：[1]南京交通职业技术学院,江苏南京211188 [2]江苏南京地质工程勘察院,江苏南京210041 [3]南京工业大学交通学院,江苏南京210009

出　　处：《江苏科技大学学报（自然科学版）》2012年第6期551-555,共5页Journal of Jiangsu University of Science and Technology:Natural Science Edition

基　　金：国家自然科学基金资助项目(50608038);江苏省自然科学基金资助项目(BK2009732)

摘　　要：预制基坑支护桩因其线形密排,桩间距较小,沉桩挤土效应比较严重,对基坑外的建(构)筑物和基坑内的桩基础产生不利影响.通过对多层土体中密排支护桩沉桩挤土效应的三维有限元分析,得出挤土过程中土体的应力与应变、水平位移与竖直位移的变化规律;即水平位移随距桩心的距离加大而急剧衰减,在距排桩轴心两侧5～8倍桩径范围内,土体水平位移衰减较快;在沉桩过程中,地表土体的隆起量受桩入土深度的影响小于桩尖和桩中部土体隆起量变化,桩周附近地表水平挤土位移最大值约0.8 m左右,地表竖向挤土位移均值也在0.5 m左右.所得结论可用于指导实际工程.Because of the close packing and less pile spacing, the soil compacting effect of the precast retaining piles of the pit is remarkable, which has negative effect on the outer buildings and the inner pile foundation. Threedimensional finite element analysis on the closepacking piles in the multilayer soil is made in this paper, soil stress and strain, horizontal displacement and vertical displacement during pile driving are obtained. The horizontal displacement attenuated rapidly with the increase of the distance from the pile center. In the range of 5 -8 times the pile diameter, the horizontal displacement attenuates more quickly. The depth of pile embedding soil has less influence on the ground upheaval. The maximum horizontal displacement of the surface soil around the pile is about 0. 8 m. The mean of the vertical displacement of the surface is about 0. 5 m. The results have important engineering significance.

关 键 词：密排 支护桩 挤土效应 有限元分析 

分 类 号：TU473.1[建筑科学—结构工程]