Dynamic pressures on a pair of rigid walls experiencing base rotation and retaining poroelastic soil

The dynamic response of a pair of rigid retaining walls to horizontal harmonic ground shaking is studied analytically. The two walls are elastically constrained against rotation at their base. The retained material is idealized as a uniform, fully saturated poroelastic layer of soil of constant thickness obeying Biot’s dynamic poroelastic theory. In the analysis, emphasis is given to the calculation of the wall rotation angle. The parameters examined include mainly the rotational flexibility of the wall constraint, the properties of the retained medium and the distance between the walls. The response quantities considered include the displacement of the wall, the wall pressures, and the associated forces. It is shown that, for a system experiencing base rotation, the maximum wall forces are much lower than those obtained for fixed-based rigid walls for any combination of the soil permeability and porosity and any distance between the walls.