基坑倾斜桩梯级支护结构变形与内力分析  

Deformation and internal force analysis of inclined pile multi⁃bench retaining structure in foundation pit

作　　者：郭景琢 李松昊 郑刚[2,3] 周海祚[2,3] 王金山 GUO Jingzhuo;LI Songhao;ZHENG Gang;ZHOU Haizuo;WANG Jinshan(State Key China Construction Infrastructure Corp.,Ltd.,Beijing 100044,China;School of Civil Engineering,Tianjin University,Tianjin 300072,China;MOE Key Laboratory of Coast Civil Structure Safety,Tianjin University,Tianjin 300072,China)

机构地区：[1]中国建设基础设施有限公司,北京100044 [2]天津大学建筑工程学院,天津300072 [3]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072

出　　处：《建筑结构》2025年第4期132-138,共7页Building Structure

基　　金：中建基础科技研发课题(CSCIC-2020-KT-(01));中建股份科技研发计划资助(CSCEC-2021-Z-(25))。

摘　　要：倾斜桩技术和梯级支护技术可不使用水平支撑达到节约工期、降低造价、保护环境的目的,但目前有关基坑倾斜桩梯级支护的变形特性及桩土相互作用研究较少。通过有限元软件PLAXIS 3D对典型倾斜桩梯级支护组合结构进行了4个设计参数分析;分析了大量工况下典型设计参数对一级支护为内斜斜直交替桩梯级支护结构变形影响,对桩身弯矩、轴力等桩土相互作用特点进行了分析。结果表明:基坑一级开挖深度H1存在最优值,其值与一、二级支护能力相关,当一级支护为斜直交替桩时可取为60%的基坑开挖深度;一级支护桩的变形随一、二级支护桩间距B和一级支护桩长度L1增加而减小;斜直交替支护桩斜桩倾角θ存在最优值,其值与一级支护桩长度L1和一、二级支护桩间距B相关。The inclined pile technology and the multi⁃bench retaining technology can achieve the purpose of saving the construction period,reducing the cost and protecting the environment without using the horizontal support,but at present,there are fewer researches on the deformation characteristics and pile⁃soil interaction of inclined pile multi⁃bench retaining structure in foundation pits.The finite element software PLAXIS 3D was used to analyze the four design parameters of the typical inclined pile multi⁃bench retaining structure.The effects of typical design parameters on the deformation of the first level support for alternating inclined and straight pile multi⁃bench retaining structure were analyzed under a large number of working conditions,and the pile⁃soil interaction characteristics such as pile bending moment and axial force were analyzed.The results show that there exists an optimal value for the first level excavation depth H1 of the foundation pit,and its value is related to the capacity of the first⁃level and second⁃level support,which is 60%of the excavation depth of the foundation pit when the first⁃level support is alternating inclined and straight pile.The deformation of the first⁃level support pile decreases with the increase of distance B between the first⁃level support pile and second⁃level support pile and the length L1 of the first⁃level support pile.There is an optimal value for the inclination angle θ of the inclined pile for the alternating inclined and straight pile,which is related to the length L1 of the first⁃level support pile and the distance B between first⁃level support pile and second⁃level support pile.

关 键 词：基坑支护 梯级支护 斜直交替桩 参数分析 桩土相互作用 

分 类 号：TU473[建筑科学—结构工程]