考虑地震加速度时程影响的挡土墙动土压力分布  

Research on the Earth Pressure Distribution Behind the Retaining Wall Under Seismic Acceleration Influence

作　　者：何思明[1,2,3] 王忠福[1,2,4] 王娟[1,2] 

机构地区：[1]中国科学院山地灾害与地表过程重点实验室,四川成都610041 [2]中国科学院水利部成都山地灾害与环境研究所,四川成都610041 [3]中国科学院青藏高原地球科学卓越创新中心,北京100101 [4]中国科学院大学,北京100049

出　　处：《四川大学学报（工程科学版）》2015年第4期31-37,共7页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(41272346);"十二五"科技支撑计划项目资助(2011BAK12B03)

摘　　要：针对传统拟静力法在计算挡土墙动土压力时不能考虑地震荷载等特点的问题,采用拟动力法,考虑地震加速度随时间及挡土墙深度的变化,采用薄层分析法并结合极限平衡理论,推导了地震荷载作用下挡土墙动土压力随地震加速度时程变化的表达式,研究了墙后破裂面倾角、动土压力系数、动土压力合力作用点位置随地震时程的变化特征及地震加速度对挡土墙动土压力分布的影响。结果表明:动土压力合力作用点位置随地震加速度时程呈周期性变化,合力作用点高度高于传统方法所确定的H/3;地震荷载下挡土墙主动土压力呈非线性分布,地震加速度、内摩擦角对动土压力分布有显著影响。Assuming the variation of the seismic coefficient with height and by using the pseudo-dynamic method,the thin-layer microelement method and limit equilibrium principles,a new formulation was proposed to calculate the active seismic pressure on retaining wall. The angle of critical failure wedge,the active earth pressure coefficient and the resultant force point can be calculated using the developed formulation. The relationship between the seismic coefficient and the earth pressure distribution on retaining wall were studied.The results showed that the earth pressure coefficient is between the Coulomb＇s earth pressure coefficient and the Rankine＇s earth pressure coefficient. The resultant force point is change with the time,and is much higher than that of the traditional method about H /3.The distribution of earth pressure on retaining wall follows a non-linear pattern at each moment. The seismic coefficient and the internal friction angle have great influence on the earth pressure distribution.

关 键 词：地震 挡土墙 拟动力学方法 动土压力分布 合力作用点 

分 类 号：TU43[建筑科学—岩土工程]