Modeling and Analysis of Back-To-Back Walls with Combined Wrap-Around and Full-Height Rigid Facing for High-Speed Rail Applications

Abstract

Mumbai to Ahmedabad High-Speed Rail (MAHSR) Corridor is India's first high-speed rail line. In this project, there are many places where back-to-back geosynthetic-reinforced retaining walls have been adopted. Particularly, wrap-around geosynthetic-reinforced retaining wall with full-height rigid (FHR) facing is being envisioned. In present study, back-to-back mechanically stabilized earth (MSE) walls with various types of facia are developed using finite difference method FLAC 2D. They include (1) back-to-back MSE walls with segmental panel facing and (2) wrap-around wall with full-height rigid (FHR) facing. Segmental panel facing is conventional type facing system. In wrap-around wall with full-height facing, firstly wrap-around reinforced wall is constructed and latter a full-height rigid (FHR) facing is constructed by casting in-place concrete in such a way that it is rigidly connected to the adjacent wrapped reinforcement layers. In present study, after construction of entire wall a surcharge load of 30 kPa was applied. The stiffness of reinforcement is also varied to understand its effect on the behavior of these walls. Lateral displacements at the facing in various facing types are analyzed. It is observed that the retaining wall with FHR facing performed superior performance with respect to lateral displacements than the conventional facing. The lateral pressures at the face of the wall were also determined.KeywordsFull-height rigid facing retaining wallsBack-to-back wallsNumerical modeling of reinforced retaining wallsFLAC