Rocking Vibration of Rigid Ring Foundations

Abstract

A comprehensive analysis is made of the harmonic rocking response of massless, rigid, ring foundations supported at the surface of a homogeneous elastic half‐space. The parameters considered include the thickness‐to‐radius ratio for the ring, the frequency of the exciting force and the resulting steady state response, and Poisson's ratio for the supporting medium. The response quantities examined include the stiffness and damping coefficients of the system in an equivalent spring‐dashpot representation of the supporting medium, the rotation of the foundation, and the normal pressure at the foundation‐medium interface. The results in each case are compared with those obtained for a solid disk foundation having the same radius as the outer radius of the ring. The reported data are computed by a method of analysis which takes account of the mixed boundary conditions at the surface of the half‐space and are believed to be of high accuracy.