Calculation of Static Lateral Thrust and Its Application Point on Rigid Retaining Walls in Layered Backfill

In this paper، based on soil plasticity and pseudo-static methods، necessary equations have been derived for determination of total active thrusts due to layered backfill on rigid retaining walls using limit equilibrium approach. For this purpose، the reaction force applied on the failed wedge due to granular backfill has been determined using Kotter’s equations. The total lateral thrust and the angle of the failed wedge in the backfill with the horizontal direction has also been computed for both active and passive conditions. In addition، heights of application points of these thrusts have been calculated and compared with those obtained from earlier research work. Moreover، the method has been expanded for layered backfill. The results show that the total resultant thrust obtained from this study is well in accordance with the Coulomb method. In addition، it has been shown that the point of application of the resultant thrust depends on the backfill layering and backfill properties. Moreover، the developed method has shown that for retaining walls rotating sufficiently about their toes، overturning moments computed from the Coulomb method are on the safe side.