Numerical Investigation of At-Rest Earth Pressure to Rigid Retaining Walls under Cyclic Surcharges

One of the most important factors in the design of retaining walls is to determine the earth pressure acting on such walls. In this paper in order to study the at-rest earth pressure to rigid retaining walls, a fixed retaining wall with a cohessionless dry backfill is modeled with the computer program FLAC 2D. The geometrical and mechanical properties of the numerical model are based on the physical model developed in the laboratory. To verify the model, the results of the numerical model are compared to the results of the experimental model. Then cyclic surcharges with different amplitudes and frequencies are applied in different distances from the wall and the pressure distribution on the wall, the resultant force and its point of application are investigated. The effect of soil, wall and loading parameters on the cyclic pressure are also evaluated. The results of the model show that the pressure distribution to the retaining wall under cyclic surcharge is nonlinear and there is a significant increase in the earth pressure due to cyclic loading compared to that due to static loading.