基于变形控制的悬臂式支护结构嵌固深度计算方法  

Deformation Controlled Calculation Method for the Embedded Depth of Cantilever Retaining Structure

作　　者：范晓真 刘东海 徐立明 陈其志 徐长节[1,2,6] 方焘 FAN Xiaozhen;LIU Donghai;XU Liming;CHEN Qizhi;XU Changjie;FANG Tao(Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou 310058,China;Engineering Research Center of Urban Underground Development of Zhejiang Province.,Zhejiang University,Hangzhou 310058,China;Hangzhou Chengdong New City Construction Investment Cp.,Ltd.,Hangzhou 310000,China;Zhejiang Hanghai Intercity Railway Co.,Ltd.,Jiaxing 314000,China;School of Architectural Engineering Institute,Zhejiang University of Science and Technology,Hangzhou 310012,China;Jiangxi key laboratory of infrastructure safety control in geotechnical engineering,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]浙江大学,滨海和城市岩土工程研究中心,浙江杭州310058 [2]浙江省城市地下空间开发工程技术研究中心,浙江杭州31OO58 [3]杭州市城东新城建设投资有限公司,浙江杭州310000 [4]浙江杭海城际铁路有限公司,浙江嘉兴314000 [5]浙江科技学院土木与建筑工程学院,浙江杭州310012 [6]华东交通大学江西省岩土工程基础设施安全与控制重点实验室,江西南昌330013

出　　处：《应用基础与工程科学学报》2022年第2期434-445,共12页Journal of Basic Science and Engineering

基　　金：国家杰出青年科学基金项目(51725802);国家重点研发计划目(2015CB057801);国家自然科学基金项目(51878276);浙江省自然科学基金委员会-华东院联合基金(LHZ19E080001);江西省自然科学基金重点项目(20192ACB20001)。

摘　　要：随着我国基本建设工程的进一步推进,基坑工程设计理论水平也得到了很大的发展,传统的按承载力设计的方法正逐渐过渡为按变形控制设计.基于提出的考虑位移的非极限状态土压力计算方法,以支护结构的位移为控制变量,通过力矩平衡建立并求解了悬臂式基坑支护结构的抗倾覆稳定控制方程,可获得基于变形控制的悬臂式支护结构临界嵌固深度.根据计算结果,进一步分析了支护结构与土体间外摩擦角、土体内摩擦角、基坑开挖深度以及支护结构控制位移等参数对支护结构临界插入比的影响.研究结果表明:外摩擦角和土体内摩擦角越大,越有利于支护结构的稳定,支护结构的临界插入比越小;传统极限平衡法获得的插入比计算结果偏于不安全,且不安全程度随内摩擦角减小加剧;基坑支护结构的控制位移对临界插入比具有显著影响,控制位移越小临界插入比越大,开挖深度较大时插入比受控制位移影响更明显.The development of urban construction in China during the past few decades resulted in the great development of excavation engineering design methods.The traditional design methods are undergoing a transition from bearing capacity based control to deformation based control.Based on the proposed displacement-dependent lateral earth pressure model,the anti-overturning stability governing equation was established and solved using moment equilibrium equation.Taking the deformation of retaining wall as the control variable,the critical anti-overturning embedded depth of rigid retaining wall was obtained.The influencing factors of the critical insertion ratio of retaining wall,including the external and internal friction angles,excavation depths and the control displacement of retaining wall,were investigated.Research indicates that,the greater the external and internal friction angles,the better the stability of retaining wall,and the smaller the critical insertion ratio.The insertion ratios obtained by traditional limit equilibrium method are unsafe,and the degree of insecurity is more serious when the internal friction angle is relatively small.The controlled displacement of retaining wall has a significant influence on the critical insertion ratio.The smaller the control displacement,the larger the critical insertion ratio and the faster the insertion ratio increases.The insertion ratio is more obviously effected by the control displacement while the excavation depth is relatively large.The proposed calculation method can be used for the design of rigid retaining structure based on deformation control.

关 键 词：非极限状态土压力 变形 悬臂式支护结构 临界插入比 嵌固深度 设计计算方法 

分 类 号：TU470[建筑科学—结构工程]