Seismic passive earth pressure against the retaining wall considering the structure and principal stress rotation of loess
CHEN Fei;SHAO Shengjun;Institute of Geotechnical Engineering,Xi'an University of Technology;Shaanxi Provincial Key Laboratory of Loess Mechanics and Engineering;
There are some drawbacks about the method of existed seismic passive earth pressure calculation in loess areas. Plane strain tests with four water contents and three confining pressures are conducted,the relationship between strength parameters and structure of loess is firstly established here. Formula of lateral earth pressure coefficient considering deflection of stress principal axis is extended in the passive state of cohesive soil. The new calculating method of seismic passive earth pressure simultaneously considering the structure and deflection of principal stress is put forward through horizontal slices analysis. The parametric analysis show the seismic passive earth pressure in the plane strain or having the structure of soil condition is larger than that in triaxial or without structure of soil condition. Friction of soil-wall interface makes seismic passive earth pressure increasing. With the increasing of the horizontal and vertical seismic acceleration coefficients,the seismic passive earth pressure is gradually decreasing. The contrary effects are produced in the friction angle,uniform load,friction angle in the interface of wall and soil,cohesion and structural index. The influence of the strength parameters of plane strain,the structure of soil and the effect of wall-soil friction should be taken into consideration in the calculation of the dynamic earthpressure of the earthquake in the loess area.