Influence of non-breaking wave force on seismic stability of seawall for passive condition

Proper design of seawall in earthquake prone region is one of the major concerns in geotechnical earthquake engineering. This paper presents the stability analysis of seawall under the combined action of earthquake forces, non-breaking wave force, hydrostatic and hydrodynamic forces and uplift force. Stability of seawall is assessed in terms of its factor of safety against landward sliding and landward overturning modes of failures. Seismic passive earth resistance has been calculated using pseudo-static approach. A detailed parametric study has been conducted to study the effect of non-breaking wave height, depth of water on seaward and land ward sides, soil and wall friction angles, and horizontal and vertical seismic accelerations. The factor of safety against overturning mode of failure decreases by about 52%, for a change in the ratio of non-breaking wave height to the depth of water on seaward side from 0 to 0.60. Present study shows that the seismic stability of seawall is more sensitive to non-breaking wave height, soil friction angle, wall friction angle and horizontal seismic acceleration. Proposed closed-form solutions and design charts can be used for the seismic design of seawall for passive case under the combined action of earthquake and non-breaking wave forces. •Non-breaking waves influence significantly on seismic stability of seawalls.•Pseudo-static passive earth pressure with hydrodynamic condition is taken.•Both sliding and overturning modes of failures of seawalls are considered.•Closed-form design solutions for factor of safety of wall are proposed.•New solutions for combined seismic and non-breaking waves on seawalls.