Based on SSI Principals Presented by Professor Jonathan P. Stewart Prof. Civil Engineering, UCLA Link to flyer here During earthquake ground shaking, earth pressures on retaining structures can cyclically increase and decrease as a result of inertial forces applied to the walls and kinematic interactions between stiff wall elements and surrounding soil. The current state of practice is based on a limit analysis approach in which a pseudostatic inertial force is applied to a soil wedge behind the wall. This…