Combined influence of wave and earthquake loading on external stability of waterfront reinforced soil wall

Waterfront reinforced soil walls (WRSWs) are susceptible to various modes of failure mechanism under dynamic loading conditions developed by earthquakes and water waves near the coastal regions. This study presents an external stability analysis of WRSWs founded on cohesive-frictional soil strata, subjected to both earthquake and wave forces. A simple pseudostatic approach was used for the stability analysis of wall and to assess the minimum reinforcement length required against different failure modes using a limit equilibrium method for various design parameters including horizontal and vertical seismic acceleration coefficient (k h and k v ), pore pressures ratio (r u ), cohesion of soil (c), wave height (h 1 ) and wavelength (l). Critical stability was defined when the safety factor reached unity. From the analysis, it is observed that the requirement of geosynthetic reinforcement increases with an increase in the level of water in the backfill along with an increase in the ratio of wave height to the depth of water and increment in the value of k h and k v . Conversely, an increase in cohesion component in backfill soil (c 0 ) demonstrates a significant reduction in the total required reinforcement length 74.65% and 80.46% for ϕ m = 25° and 35° respectively at k h = 0.1 and other constant parameters. This research addresses a critical gap by exploring the combined effect of seismic and wave loading on the external stability of WRSWs.