Stability analysis of geosynthetic-reinforced soil structures under steady infiltrations

Conventional approach for evaluation of the stability of geosynthetic-reinforced soil structures (GRSSs) is performed under either completely dry or saturated conditions, whereas soils are usually unsaturated in practice. Owing to the suction-induced effect, the behavior of soil is quite different, consequently leading to various stability conditions of GRSSs. This study presents a useful analytical solution for assessing the reinforcement effect of geosynthetics on the internal stability of unsaturated GRSSs under steady infiltration conditions using the kinematical approach of limit analysis, aiming at determining the reinforcement strength required for preventing slope failure. This analytical solution can take the effect of suction stress, unit weight of soil and tensile strength cut-off simultaneously into account. By comparing with the results of other solutions, the validity of the analytical solution is verified. An extensive parametric study is conducted in this paper. The obtained results show that the suction stress has a more significant effect than the tensile strength cut-off on the required normalized reinforcement; additionally, the required normalized reinforcement obtained by the extended M-C yield criterion is more conservative than that of the tension cut-off model in the presence of suction stress, and the hysteresis effect should be considered in the routine design.

Automated summary

This study presents an analytical solution for assessing the internal stability and required reinforcement strength of unsaturated GRSSs under steady infiltration conditions, taking into account the effects of suction stress, soil unit weight and tensile strength cut-off. The results indicate that suction stress has a more significant impact on the required reinforcement, and the extended M-C yield criterion is more conservative in the design process.