RBT模式下刚性挡墙非极限主动土压力的离散元模拟及理论研究  

Discrete element simulation and theoretical study on non-limit active earth pressure of rigid retaining wall under RBT mode

作　　者：姚嘉楠 徐长节[1,2,3] 迟民良 王艳萍 习跃来 王伟锋 冯国辉 孙佳政 YAO Jia-nan;XU Chang-jie;CHI Min-liang;WANG Yan-ping;XI Yue-lai;WANG Wei-feng;FENG Guo-hui;SUN Jia-zheng(Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou,Zhejiang 310058,China;Engineering Research&Development Centre for Underground Technology of Jiangxi Province,East China Jiaotong University,Nanchang,Jiangxi 330013,China;Jiangxi Key Laboratory of Infrastructure Safety Control in Geotechnical Engineering,East China Jiaotong University,Nanchang,Jiangxi 330013,China;Zhejiang Infrastructure Construction Group Co.,Ltd.,Hangzhou,Zhejiang 310012,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]华东交通大学江西省地下空间技术开发工程研究中心,江西南昌330013 [3]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 [4]浙江省建投交通基础建设集团有限公司,浙江杭州310012

出　　处：《岩土力学》2025年第2期640-652,共13页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52238009);国家自然科学基金–高铁联合基金(No.U1934208);江西省自然科学基金–揭榜挂帅资助项目(No.20223BBG71018)。

摘　　要：针对刚性挡墙绕基底转动与平动耦合(rotation around the base and translation coupling,简称RBT)模式下砂土非极限主动土压力的分布问题,选取转动中心位置参数n=0.5、1.0、5.0共3组转动中心对其进行离散元模拟研究。结果表明,RBT模式下主动土压力兼具绕基底转动(rotation around base,简称RB)模式下凹型分布和平动(translational,简称T)模式直线分布的特点。在破坏过程中,墙土摩擦角往往先于内摩擦角达到极限值,墙后滑裂面为一曲面,且土体滑裂面处有明显的主应力偏转现象。基于数值模拟结果,根据中间对称圆弧拱得到了层间等效内摩擦角与n的函数关系式,利用水平层分析法,建立了曲边梯形微分单元的受力平衡方程,采用有限差分法求解得到了RBT模式非极限主动土压力数值解。参数分析表明,墙体位移、内摩擦角及转动中心位置参数n对主动土压力具有显著的影响。通过与数值模拟和模型试验的对比,验证了所提理论的合理性和可靠性,研究成果可为刚性挡土墙土压力计算提供参考。This study investigates the distribution of non-limit active earth pressure in sand under the rotation around the base and translation coupling(RBT)mode of rigid retaining wall.Three groups of position parameter of rotation center(n=0.5,1.0,and 5.0)are selected for discrete element simulation study.The results indicate that the active earth pressure in RBT mode exhibits both concave distribution characteristics of the rotation around base(RB)mode and linear distribution characteristics of the translational(T)mode in rigid retaining walls.During failure,the wall-soil friction angle usually reaches its limit value before the internal friction angle.The slip surface behind the wall forms a curve,with a noticeable principal stress deflection at the soil slip surface.Based on the numerical simulation results,the relationship between the equivalent internal friction angle of the interlayer and the position parameter of rotation center n is derived using the middle symmetrical arc arch.The force equilibrium equation for the curved trapezoidal differential unit is established using the horizontal layer analysis method,and the numerical solution for non-limit active earth pressure in RBT mode is obtained using the finite difference method.Parameter analysis shows that displacement,internal friction angle and n significantly affect the active earth pressure.Comparison of numerical simulations and model tests verifies the rationality and reliability of the theory presented in this paper.The findings provide a valuable reference for calculating earth pressure in rigid retaining walls.

关 键 词：RBT模式 非极限主动土压力 离散元法 土拱效应 层间等效内摩擦角 水平层分析法 

分 类 号：TU432[建筑科学—岩土工程]