Dynamic soil structure interaction model for beams on viscoelastic foundations subjected to oscillatory and moving loads

A new method for dynamic analysis of Euler-Bemoulli beams resting on multi-layered viscoelastic soil is presented. The governing differential equations for beam and soil displacements are obtained using the extended Hamilton's principle, and these equations are solved using one-dimensional finite element method and analytical solutions. An iterative solution algorithm is used in conjunction with an implicit time integration scheme to obtain beam and soil responses as functions of time. The developed model resembles the traditional two-parameter spring foundation model but the analysis shows that the traditional foundation spring parameters cannot be prescribed a priori but determined as part of the solution. The model produces accurate beam response as illustrated by comparisons with equivalent two-dimensional finite element analysis. A few problems are analyzed that illustrate the novel features of the dynamic foundation model.