Shake Table Studies to Assess the Effect of Reinforced Backfill Parameters on Dynamic Response of MSE Walls

Abstract

AbstractThe mechanically stabilized earth retaining wall offers several benefits in various areas of geotechnical engineering. Due to the interaction between backfill soil and reinforcement, the MSE wall behaves like a coherent structure. Thus, suitable to sustain substantial loading. The purpose of this study is to analyze the seismic behavior of geogrid reinforced soil retaining walls under three different input motions. The influence of relative densities of fine backfill sand and the number of reinforcing layers was studied using shaking table tests.1-D shake table tests were performed on small scale retaining wall models with two and three layers of geogrid. Six models were constructed and instrumented with LVDTs and accelerometers to study the performance of the wall and backfill. Base excitations with three different peak ground acceleration (PGA) values were provided to all these models. The lateral displacement and acceleration amplification factors (AAF) were assessed at different elevations for every model. It was witnessed that the acceleration amplification factor (AAF) was more at the wall panels as compared to sand backfill for the same elevation. The AAF was higher in dense soil backfill as compared to the loose state. The experimental results also indicated that, with the increase in the relative density of backfill, the horizontal face displacement decrease. Hence, it can be concluded that retaining walls with fine sand backfill in the dense condition performs better in terms of displacement under dynamic loads.KeywordsMechanically stabilized earth (MSE) wallShake table testGeogridPeak ground accelerationAcceleration amplification factor