桩-锚支护深基坑开挖的有限元分析  

FINITE ELEMENT ANALYSIS OF EXCAVATION OF DEEP FOUNDATION PIT WITH PILE-ANCHOR SUPPORT

作　　者：张群 赵延林 ZHANG Qun;ZHAO Yanlin(School of Architecture Engineering,Heilongjiang University of Science&Technology,Harbin 150000,China)

机构地区：[1]黑龙江科技大学建筑工程学院,哈尔滨150000

出　　处：《低温建筑技术》2020年第1期96-99,119,共5页Low Temperature Architecture Technology

基　　金：2018年黑龙江省大学生创新创业训练计划项目(201810219028)。

摘　　要：为研究深基坑开挖对基坑及周围土体的位移影响,采用有限元软件ABAQUS模拟基坑开挖过程,对基坑内部、支护结构及临近土体位移进行研究。研究表明开挖初期,基坑后侧土体沉降最大处位于开挖深度1~2倍距离范围;开挖深度增大,基坑后侧土体沉降出现两个极值,分别发生锚杆自由段与锚杆尾部处;开挖深度较大时,在靠近支护桩位置出现大于基坑中心位置隆起量的凸起。支护结构最大侧移点位于坑底以上2~3m处。增加锚杆预应力或支护结构刚度,结构最大侧移、支护桩附近回弹凸起、坑后锚杆自由段处沉降量均减小,刚度增加前期的侧移控制效果更为显著。增加锚杆预应力,支护结构最大侧移点下降至坑底以下,排桩变形由“大肚子”状逐渐变为“S”形。In order to study the influence of deep foundation pit excavation on the displacement of foundation pit and surrounding soil,the finite element software ABAQUS was used to simulate the foundation pit excavation process,and the internal pit,supporting structure and adjacent soil displacement were studied.The research shows that at the initial stage of excavation,the maximum settlement of the soil on the back side of the foundation pit is within the distance of 1~2 times of the excavation depth;the excavation depth increases,and two extreme values of the settlement of the soil on the back side of the foundation pit appear,respectively at the free section and the tail end of the anchor;when the excavation depth is large,a protrusion larger than the central position uplift of the foundation pit is present near the support pile.The maximum lateral displacement point of the supporting structure is located 2~3m above the bottom of the pit.Increase the prestress of the bolt or the stiffness of the supporting structure,the maximum lateral displacement of the structure,the rebound bulge near the retaining pile,and the settlement at the free section of the post-pile anchor are all reduced,and the lateral shift control effect in the early stage of the stiffness increase is more significant.The prestress of the bolt is increased,and the maximum lateral displacement point of the supporting structure falls below the bottom of the pit,and the deformation of the row pile gradually changes from the“big belly”shape to the“S”shape.

关 键 词：桩锚支护 沉降 侧移 

分 类 号：TU473.2[建筑科学—结构工程]