深基坑开挖中支护结构参数优化设计  

Optimization Design of Supporting Structure Parameters in Deep Foundation Pit Excavation

作　　者：叶永[1] 刘杨 谢旋 YE Yong;LIU Yang;XIE Xuan(College of Hydraulic&Environmental Engineering,China Three Gorges Univ.,Yichang 443002,China)

机构地区：[1]三峡大学水利与环境学院,湖北宜昌443002

出　　处：《三峡大学学报（自然科学版）》2023年第3期14-19,共6页Journal of China Three Gorges University：Natural Sciences

基　　金：国家重点研发计划(2021YFC3001903);国家自然科学青年基金(11802162)。

摘　　要：支护结构严重影响深基坑开挖变形,已有研究缺乏对支护结构进行整体协同优化.本文利用MIDAS GTS NX有限元软件进行支护结构多参数对基坑开挖变形影响机理分析.研究了锚杆入射角、围护桩厚度和深度等结构参数对坑外土沉降和围护桩水平位移的影响机理,并对支护结构参数进行优化设计.结果表明:锚杆入射角对基坑隆起影响不大,对坑外土沉降有一定的影响,对围护桩水平位移影响较大;围护桩厚度、深度对坑外土沉降、围护桩水平位移都有影响.通过参数组合计算发现锚杆最优入射角为25°左右,同时改变围护桩的深度和厚度,在保证桩侧向位移不增加条件下,桩总体积可以减小20%,由此得到实际工程深基坑支护结构的最优方案,并通过现场监测数据进行了验证.研究结果为深基坑支护结构优化设计和变形验算提供技术支撑和应用参考.The supporting structure seriously affects the excavation deformation of deep foundation pit,and the overall collaborative optimization of the supporting structure is usually lacked in previous studies.In this paper,MIDAS GTS NX finite element software was used to analyze the influence of multiple parameters of supporting structure on the deformation of foundation pit excavation.The influence mechanism of structural parameters such as incident angle of bolt,thickness and depth of retaining pile on soil settlement outside the pit and horizontal displacement of retaining pile is studied.Then,the parameters of supporting structure are optimized.The results show that the incident angle of the bolt has little influence on the uplift of the foundation pit,but has a certain influence on the settlement of the soil outside the pit and has a great influence on the horizontal displacement of the retaining pile.The thickness and depth of retaining pile have influence on soil settlement outside the pit and horizontal displacement of retaining pile.Through parameter combination calculation,it is found that the optimal incident angle of the bolt is about 25°,and the total pile volume can be reduced by 20% under the condition that the lateral displacement of the pile is not increased by changing the depth and thickness of the retaining pile.Therefore,the optimal scheme of the retaining structure of the deep foundation pit in actual engineering is obtained,and verified by the on-site monitoring data.The research results provide technical support and application reference for the optimization design and deformation checking of deep foundation pit retaining structure.

关 键 词：深基坑 桩锚支护结构 基坑位移 优化设计 MIDAS GTS NX 

分 类 号：TU476[建筑科学—结构工程]