Study on Soil–Panel Interaction on the Performance of MSE Wall

Abstract

The mechanically stabilized earth (MSE) wall is used as a substitute structure for conventional cantilever walls and gravity walls. Performance of the MSE wall mainly depends upon the backfill and foundation soil type and interaction between soil with facing panels. Parametric analyses using a two-dimensional FEM tool PLAXIS are carried out to investigate the influence of backfill soil stiffness, foundation soil stiffness, and panel–soil interface shear on MSE wall performance. MSE wall of height 16 m is considered for the analysis. The PLAXIS plate elements are used for the concrete panels. The soil zones are modeled as linear-elastic material with Mohr–Coulomb failure criterion. Five different backfill soils and three different foundation soils were considered in this investigation. The range of elastic modulus values for the backfill soil corresponds to the range of elastic secant modulus values computed at 50% of the failure deviatoric stress for three different soils compacted to different densities. To keep the numerical modeling simple, no attempt is made to simulate compaction effects by applying a transient surcharge pressure at each soil layer during construction. The effect of interaction friction coefficient (R = tan δ/tan ϕ) between backfill soil and concrete panel is considered in the analysis. The values of R used in the study range from 0.3 to 0.6. Extreme horizontal (Ux), vertical deformations (Uy), and total deformations (Ut) are obtained for backfill soil stiffness varying from 10 to 100 MPa and foundation soil stiffness varying from 10 to 1000 MPa.KeywordsFEMBackfill soilSoil stiffnessDeformationsInteraction friction coefficient