Analytical solution of seismic active lateral force in retaining walls using stress fields

In this paper, application of stress fields in computation of seismic active lateral forces on retaining walls is considered using the lower bound method of limit analysis. Finding the exact solution of boundary value problems in engineering fields is a complicated problem in most applied cases and from this point of view, use of the limit state methods is very beneficial for engineers. In limit analysis method, in spite of exact solution of the problem, the upper and lower bound of the limit load are determined. The lower bound of the exact solution can be obtained by use of different admissible stress fields in different regions of the media divided by stress discontinuity surfaces. Earthquakes have unfavorable effects of increasing active and decreasing passive lateral earth pressure, so to investigate how the lateral earth pressure is affected, extensive numerical results based on the limit analysis method reported by Chang and Chen. This paper is devoted to finding an Analytical solution to investigate the lateral force affection on retaining walls, using mathematical relations based on lower bound limit analysis method. This process include the calculation of direction and magnitude of active lateral earth pressure. Numerical results of the proposed algorithm are presented in some practical dimensionless graphs.