Effect of Rainfall on Performance of Reinforced Earth Wall

This paper presents the results of a numerical investigation on the effect of rainfall on the performance of a reinforced earth wall. A series of limit-equilibrium based slope stability analyses within the framework of unsaturated shear strength, coupled with transient infiltration analyses considering actual rainfall record were performed to quantify the effect of rainfall on the performance of the reinforced earth wall in terms of factor of safety. A parametric study was additionally conducted on the rainfall intensity. The results indicated that the reinforced wall stability, in terms of factor of safety, could be significantly decreased when subject to rainfall due to decrease in shear strength of backfill casued by the reduction in matric suction. Also shown is that there appears to exist a critical rainfall volume beyond which no further significant decrease in the factor of safety occurs. Practical implications on the findings of this study will also be discussed.