摘要
滑裂面的搜索方法及安全系数的计算理论是深基坑桩锚支护结构稳定性分析理论的基础。传统圆弧滑动法在分析抗滑力矩的过程中,滑裂面法向应力的计算存在过多假设;且在通过网格搜索法确定最危险滑裂面圆心的过程中,粗糙网格的搜索结果误差较大,精细网格的搜索效率较低。基于以上问题,提出了分析基坑动态稳定性的土体强度冗余法,并采用了可提高精细网格搜索效率的自适应网格搜索法。通过算例将土体强度冗余法、滑动面应力法及圆弧滑动法的计算结果进行对比。计算结果表明,滑动面应力法高估了对滑裂面附近土体的抗剪强度,圆弧滑动法不能考虑土方开挖对桩后土体抗剪强度的削弱作用,土体强度冗余法能合理反映基坑的整体稳定性。
The stability analysis of pile-anchor retaining structure is based on the searching method of the sliding surface and the calculating theory of the safety factor.During the process of analyzing anti-sliding moment,conventional slip circle method of slices has too many assumptions.At the same time,during the process of searching for the most dangerous sliding surface,there are some problems with the grid-search method.If the rough grid is applied,the result will be less accurate.However,if the fine grid is applied,the efficiency will be lower.To solve these problems,the soil strength redundancy method is proposed in order to analyze dynamic stability of foundation pit.Also,adaptive grid-search method is used to ensure accuracy and efficiency.Finally,this paper compareds the soil strength redundancy method,the sliding surface stress method and the slip circle method of slices.The results show that the sliding surface stress method overestimates the overall stability of the foundation pit and that the slip circle method of slices cannot consider the weakening effect on the shear strength of the soil behind the pile caused by excavation.Also,the soil strength redundancy method can reflect the overall stability of the foundation pit.
作者
周勇
赵元基
王正振
ZHOU Yong;ZHAO Yuan-ji;WANG Zheng-zhen(Key Laboratory of Disaster Mitigation in Civil Engineering of Gansu Province,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Western Center of Disaster Mitigation in Civil Engineering,Ministry of Education,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;School of Civil Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2022年第S01期641-649,共9页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51568042)
教育部长江学者和创新团队发展计划(No.IRT_17R51).
关键词
基坑工程
桩锚支护结构
稳定性
强度冗余法
自适应网格搜索
excavation engineering
pile-anchor retaining structure
stability
strength redundancy method
adaptive grid-search method
作者简介
第一作者:周勇,男,1978年生,博士,教授,博士生导师,主要从事深基坑开挖支护和边坡加固方面的教学与研究工作。E-mail:gsutzhouy@163.com
