基于离散元模拟的不同挡土墙位移模式下非极限主动土压力  

Non-limit Active Earth Pressure under Different Retaining Wall Displacement Modes Based on Discrete Element Simulation

作　　者：张帆 殷铭 孙峰[3] 冯国辉 孙佳政 刘冠水 林刚 李强 徐长节[5,7] ZHANG Fan;YIN Ming;SUN Feng;FENG Guo-hui;SUN Jia-zheng;LIU Guan-shui;LIN Gang;LI Qiang;XU Chang-jie(Zhejiang Geological and Mineral Exploration Institute Co.,Ltd,Hangzhou 310013,China;Reconnaissance and Qiantang River Administration Design Institute,Co.,Ltd.of Zhejiang Province Hangzhou 310016,China;China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430061,China;Department of Civil Engineering,Hangzhou City University,Hangzhou 310015,China;Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou 310058,China;Zhejiang Hanghai Intercity railway Co.,Ltd.,Jiaxing 314000,China;State Key Laboratory of Performance Monitoring Protecting of Rail Transit Infrastructure,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]浙江省地矿勘察院有限公司,杭州310013 [2]浙江省钱塘江管理局勘测设计院有限公司,杭州310016 [3]中铁第四勘察设计院集团有限公司,武汉430061 [4]浙大城市学院土木工程系,杭州310015 [5]浙江大学滨海和城市岩土工程研究中心,杭州310058 [6]浙江杭海城际铁路有限公司,嘉兴314000 [7]华东交通大学,轨道交通基础设施性能监测与保障国家重点实验室,南昌330013

出　　处：《科学技术与工程》2024年第11期4658-4668,共11页Science Technology and Engineering

基　　金：国家重点研发计划(2023YFC3009400);国家自然科学基金(U1934208,52238009,52008373,51878276);国家杰出青年基金(51725802);江西省自然科学基金(20223BBG71018);浙江大学平衡建筑研究中心配套资金资助项目(20203512-10C);南昌轨道交通集团科研项目(2019HGKYB002)。

摘　　要：针对刚性挡土墙主动位移过程中砂土非极限主动土压力问题,利用PFC 2D分别对挡土墙绕墙顶转动(RB)模式、绕墙顶转动(RT)模式和平动(T)模式下砂土主动破坏过程进行模拟分析。分析结果表明,不同位移模式下土体内摩擦角及墙土摩擦角调动规律存在差异。挡土墙主动位移过程中,RB模式下土体破坏从墙顶开始,向墙脚发展,土楔体内部只有靠近墙背侧区域出现主应力偏转现象,并且土楔体中内摩擦角调动值均能达到极限值。RT模式下,土体破坏沿着墙背和滑裂面从墙脚开始,向土体表面发展,墙后土楔体中上部区域主应力偏转角度较大,形成了大主应力拱,与此对应的是该区域内摩擦角调动值相对初始内摩擦角减小。T模式下,土体破坏分别沿着墙背从墙顶向墙脚发展以及沿着滑裂面从墙脚向土体表面发展,墙后土楔体内部会出现小主应力拱,且内摩擦角调动值从初始内摩擦角增加,但达不到极限值。Aiming at the problem of non-limit active earth pressure of sand during active displacement of rigid retaining wall,the active failure process of sand under rotating about the base(RB)mode,rotating about the top(RT)mode and translation(T)mode was simulated and analyzed by using PFC 2D.The results show that there are differences in the mobilization of internal friction angle and the soil-wall interface friction angle in soil under different displacement modes.During the active displacement of the retaining wall,the soil failure in RB mode starts from the top of the wall and develops to the foot of the wall.Only the area near the back of the wall appears the principal stress deflection in the soil wedge,and the mobilized value of the internal friction angle in the soil wedge can reach the limit value.In RT mode,the soil failure starts from the foot of the wall to the soil surface along the back of the wall and the sliding surface.The deflection angle of the principal stress in the middle and upper part of the soil wedge behind the wall is large,forming a large principal stress arch,which corresponds to the reduction of the mobilized value of the friction angle in this area relative to the initial internal friction angle.In T mode,the soil failure develops from the top of the wall to the foot of the wall along the back of the wall and from the foot of the wall to the surface of the soil along the slip surface.A small principal stress arch appears in the soil wedge behind the wall,and the mobilized value of the internal friction angle increases from the initial internal friction angle,but it does not reach the limit value.

关 键 词：非极限主动状态 离散元模拟 土压力 墙土摩擦角 土拱效应 

分 类 号：TU432[建筑科学—岩土工程]