Interaction mechanisms in small-scale model MSE walls under the strip footing load
Hamzeh Ahmadi, Adam Bezuijen, Jorge G. Zornberg
Abstract
The effect of preloading on mechanically stabilised earth (MSE) has remained an aspect difficult to quantify in design, particularly when considering different reinforcement types, stiffness values, and facing rigidity. This study analyses several scaled model tests on MSE walls under a strip footing load with a single unloading-reloading cycle. Scaled models were constructed as part of this investigation to expand the evaluation of previously constructed full-scale tests. The strip footing load and wall deflections were measured and compared with analytical models. The failure mechanism of the soil, before and after the strip footing load, was included in the study via the particle image velocimetry (PIV) method. The results indicate that the bearing capacity of a strip footing is higher for a rigid facing than for a flexible facing. PIV analysis results for the first and second loading step formed two failure lines with the angle (π/4 + φ/2). The deflection values in the second loading step, however, were smaller than those reached during the first loading in small-scale tests. Good agreement was observed between the proposed analytical method and experimental results for the second loading step, after taking into account the preloading effect.