Study of Direct Finite Element Method of Analysing Soil–Structure Interaction in a Simply Supported Railway Bridge Subjected to Resonance

Abstract

This paper presents the dynamic soil–bridge interaction under high-speed railway lines, under different soil stiffness conditions. Starting from the analysis of a simply supported Euler–Bernoulli beam model subjected to moving loads, a three-dimensional multi-body (soil–abutment–bridge–ballast–sleeper–rail) model formulated in the time domain to study the vibrations induced due to the passage of moving concentrated loads was analysed using the direct finite element method of soil–structure interaction analysis. The high-speed train was considered to be a set of concentrated loads, the rail was modelled as a Euler–Bernoulli beam (frame element), and the sleepers, ballast, bridge, abutments and soil were modelled using eight-node solid (brick) elements. Layered soil stratum’s effects on the dynamic response of the bridge deck and variation of stresses were studied. From this study, it was observed that the direct method of FE analysis can be an effective tool to solve the complex dynamic soil–structure interaction problems.