Vertical vibration analysis of rigid footings on a soil layer with a rigid base

A simple semi-analytical method is developed to compute the response of a rigid footing subjected to a harmonic excitation and resting on a layered soil deposit with a noncompliant rock or rock-like material at the base. The method is based on variational principles and minimization of energy using Hamilton's principle. Nondimensional equations are developed for a rigid strip and circular footings resting on a layered soil media with constant or variable modulus lying on a rigid rock at the base. The method is relatively simple to use and has the ability to provide variable elastic modulus of the soil with depth. Dynamic response characteristics are plotted using nondimensional parameters.