Seismic Internal Stability Analysis of Modular Block Reinforced Earth Retaining Wall

In India, Mechanically Stabilized Earth (MSE) walls are used extensively for flyovers in highways, slope protection works, and railway and airport projects. Recently, many failures of MSE walls have been reported and these wall failures resulted in excessive deformations or collapsed altogether. The primary causes could be insufficient or improper design and construction. In particular, a focus on stability analysis and design is needed. This study focuses on detailed static and seismic stability analysis taking into consideration the effect of various vital parameters. This study mainly aims at numerical modeling using FEM and analytical calculations as per the guidelines of AASHTO, BS8006, and China railway code TB10025. Parametric analysis has been carried out using a numerical tool GEO5, considering the effect of soil type, wall-fascia inclination, the vertical spacing between reinforcements, soil reinforcement interaction, the tensile strength of reinforcement, and surcharge magnitude. Internal stability results of Modular Block Reinforced earth retaining wall (MBW) obtained from AASHTO, BS 8006, and China Railway code TB 10025 design guidelines, show that safety factors against pullout and rupture are in close range. Backfill soil with well-graded gravel (GW), well-graded sand (SW), and poorly graded gravel (GP) has yielded good results for internal stability. The Factor of Safety (FS) against pullout failure is reduced by 15–50%, as the inclination angle increases from 50 ° to 90 ° . FS values against pullout, rupture and slip are higher for a greater number of reinforcements. FS values against pullout, rupture and slip are higher for a greater number of reinforcements. Pullout and slip resistance in the reinforcement is independent of the tensile strength of the reinforcement. For lesser magnitudes of surcharge, FS against pullout, slip, and rupture is maximum. The conclusions derived from the results of this study give a better idea of understanding the behavior of the MSE wall associated with geotechnical materials.