软土深基坑桩撑支护选型分析及数值模拟研究  

Retaining Structure Selection and Numerical Analysis of Deep Foundation Pit Pile in Soft Soil

作　　者：刘芳 罗武 赵永志 朱汉新 杨烁 LIU Fang;LUO Wu;ZHAO Yongzhi;ZHU Hanxin;YANG Shuo(Zhuhai Institute of Architectural Design Zhuhai 519000,China)

机构地区：[1]珠海市建筑设计院,广东珠海519000

出　　处：《广东土木与建筑》2022年第1期14-17,64,共5页Guangdong Architecture Civil Engineering

摘　　要：为了积累珠海地区软土深基坑设计和施工经验,依托某深基坑支护项目对常用支护方案进行对比,利用理正深基坑计算软件选定钻孔灌注桩加混凝土内支撑方案;同时,采用MIDAS/GTS有限元软件,对基坑进行整体三维数值模拟分析,分析了基坑开挖过程中,支护桩桩身和桩后土体的水平位移、坑底隆起量、周边地表沉降量、支撑轴力及支护桩弯矩等变化规律。结果表明:基坑开挖至坑底时,支护桩水平位移曲线呈“鼓肚状”型分布,周边地表沉降曲线呈现“勺”型分布,经对比MIDAS/GTS有限元软件与理正深基坑计算结果,支护桩水平位移及支撑轴力结果吻合较好,证明计算方式的合理性。To accumulate the design and construction experience of deep foundation pit in soft soil area,common supporting schemes were compared based on a project with an excavation depth of 9.5 meters in Zhuhai.By using the calculation software Lizheng,the plan of bored pile with concrete internal support was selected.Furthermore,the MIDAS/GTS finite element software was used to perform an overall three-dimensional numerical simulation analysis of the foundation pit.The horizontal displacement of the supporting pile and the soil behind the pile,uplift of the pit bottom,surrounding surface settlement,axial force and bending moment of the retaining structure during the exca‐vation were analyzed.The results showed that when the foundation pit was excavated to the bottom of the pit,the horizontal displacement curve of the supporting piles presented a“bulging”type distribution,and the surrounding ground settlement curve presented a“spoon”type distribution.Finally,comparing the calculation results of the MIDAS/GTS finite element software and the calculation software Lizheng,the horizontal displacement of the supporting pile and the axial force of the brace were in good agreement,which showed the rationality of the calculation method in this paper.

关 键 词：桩撑支护 软土地区 深基坑 基坑变形 有限元分析 

分 类 号：TU473[建筑科学—结构工程]