Seismic Performance Assessment of Ash-Filled MSE Walls

Mechanically stabilized earth (MSE) structures are being increasingly constructed for highways, retaining walls, bridge abutments, waterfront amidst others. Granular materials are preferred choice as backfill in MSE structures due to their shear strength and adequate drainage. But in regions where locally available natural is not suitable as backfill as per the design guidelines, the option of transporting materials with the desired properties needs to be explored. In recent times the trend of utilization of industry by-products such as fly ash and pond ash, available in abundance in the vicinity, is being increasingly explored. In situations where the ash-filled MSE structures are required in earthquake-prone regions, the seismic response analysis becomes indispensable. In this very context, this research is designed to simulate the seismic response of pond ash-filled MSE wall structures using a meticulously developed finite element code. The code is validated and employed for full height panels walls of 6 m. The wall is subjected to recorded ground motions from Uttarkashi earthquake scaled to different peak ground accelerations. The seismic performance of the structure is compared with a sand backfill MSE wall and is found to be favourable. The lateral deformation of facing, vertical settlement and reinforcement strains are observed to be within the limits specified by guidelines and recommendations available in the published studies.