Earthquake design of flexible soil-retaining structures

Many soil-retaining wall structures are restrained from outward sliding movements and because of this it may not be appropriate to use the commonly applied Mononobe–Okabe (MO) method to estimate the earthquake induced pressures on them. This semi-rigid or stiff wall category includes bridge abutments, building basement walls and hydraulic structures associated with hydro-power and flood control. In the present research, finite-element analyses have been completed on cantilever walls that deform by both rotation about their base and flexure in the wall stem. The wall stiffness parameters have been varied to produce pressure distributions under earthquake and gravity loads for walls that vary from rigid to sufficiently flexible for the MO method to be applicable. The paper summarises the results of these finite-element studies. An example is presented to demonstrate how the results can be applied in the earthquake design of semi-rigid or stiff walls.