桩-锚支护深基坑变形与内力的数值模拟  

Simulation analysis of deformation and inner force in deep foundation pit supported with pile-anchor

作　　者：赵延林[1] 侯朝亚 李鹏[1] ZHAO Yanlin HOU Chaoya LI Peng(School of Civil Engineering, Heilongjiang University of Science ＆ Technology, Harbin 150022, China)

机构地区：[1]黑龙江科技大学建筑工程学院,哈尔滨150022

出　　处：《黑龙江科技大学学报》2016年第3期268-271,288,共5页Journal of Heilongjiang University of Science And Technology

基　　金：黑龙江省级领军人才梯队后备带头人基金项目

摘　　要：针对桩-锚支护基坑的受力与变形问题,应用ABAQUS模拟分析了开挖工况、锚杆支撑作用及预加轴力等因素对基坑周边土体变形影响范围、坑底隆起变形、桩身弯矩及变形的影响.结果表明：基坑开挖水平向影响范围约为2.0H,竖向影响范围约为3.0H,坑底隆起位移与基坑侧壁土体最大位移的比值为1.6 ～2.0.桩身弯矩与水平变形随基坑开挖深度的增加而增加,各工况间桩身弯矩与水平变形增幅存在较大的差别;桩身最大正弯矩、最大水平位移所在截面基本一致,并随基坑开挖深度的增加而不断下移.锚杆的存在改变了桩体的受力状态,使桩体由悬臂梁结构转变为具有弹性支撑的连续梁结构,极大减小了桩身弯矩与水平位移.This paper is motivated by the need for addressing the stress and deformation occurring in deep foundation pits supported with pile-anchors.The solution is accomplished by using the software ABAQUS to analyze the effects on the influence scope of the surrounding soil,bottom uplift deformation,moment,and deformation of piles by such factors as the excavation conditions,anchors,and pre-axial force.The analysis shows that soil has the horizontal influence scope of about 2.OH,and the vertical influence scope of about 3.0H;the ratio between the bottom uplift deformation and the maximum displacement of sidewall is about 1.6-2.0;the moment and horizontal deformation of piles tend to increase due to an increase in excavation depth,and the increasing extent of moment and horizontal deformation of piles vary greatly according to the excavation conditions;and the sections are found to be basically consistent among the maximum positive bending moment and the maximum horizontal displacement of the piles and tend to move down along with the increasing excavation depth.The way the anchors work provides a change in the stress state of the piles,turning the piles from a cantilever beam into a continuous beam with elastic supports and thus contributing to a great reduction in the moment and horizontal deformation of pile.

关 键 词：深基坑 支护桩 桩身位移 桩身弯矩 

分 类 号：TU473.2[建筑科学—结构工程]