Influence of facing toe condition on the bearing capacity of full-height panel MSE walls

Abstract

The paper presents a numerical modeling study on the bearing capacity of full-height panel, Mechanically Stabilized Earth (MSE) walls under strip footing using a validated finite element method that is based on upper-bound limit analysis (FE-UBLA). Parametric analyses were carried out to examine the influences that wall facing toe restraint conditions could have on predicted bearing capacity and failure mechanisms of MSE walls when subjected to strip footing load as a function of footing location, reinforcement design (i.e. tensile strength, length, and vertical spacing), wall height, and backfill shear strength. Results indicate that when the footing is placed on the reinforced zone, the bearing capacity is larger for MSE walls that are only free to rotate than those that can slide only. Also, the influence of facing toe restraint condition on bearing capacity gradually decreases with footing distance from the facing toward the retained zone. Additionally, the difference in predicted bearing capacity due to different toe restraint conditions becomes smaller for stronger and longer reinforcement layers. Finally, the foundation failure mechanism (FFM) usually corresponds to a larger bearing capacity relative to the compound failure mechanism (CFM) within the backfill.