Shaking table tests on reinforced soil retaining walls subjected to the combined effects of rainfall and earthquakes

Abstract

Earthquakes and rainfall often occur together, and their combined effects on reinforced soil retaining walls (RSRW) are not investigated in detail. In this paper, shaking table tests were carried out in model-scale to investigate seismic performance of RSRW subjected to the combined forces of rainfall and earthquakes. Five cases with different degrees of saturation for the model ground were considered for comparison and each wall was shaken by a horizontal motion with a peak acceleration of 0.5 g. Various mechanical quantities, such as wall deformation, horizontal and vertical effective earth pressures, pore water pressure, horizontal acceleration and reinforcement strain were monitored carefully. It was found that wall displacement and reinforcement strain at naturally dry and saturated states are larger than those at unsaturated state, meaning that suction does have an enhancement effect on the seismic performance of RSRW. Furthermore, a special film force sensor that can measure effective pressure in saturated ground accurately was used to measure the effective earth pressure along the facing panel of RSRW, based on which, the seismic performance was discussed in a systematical way.