Abstract
Dynamic response of a main structure of highway bridge under moving vehicles has been analyzed by using 2-dimensional models for a bridge and vehicles in relation to impact coefficients in design codes of bridges. In this study, 3-dimensional analytical procedure for traffic-induced vibrations of bridges is proposed for investigating the dynamic response of concrete slab and reaction force of plate girder bridge. Finite elements are used modeling girders, concrete slabs and floor systems of a bridge, and 8-degree-of-freedom system with one front and two rear axles is formulated for a heavy dump truck. Simultaneous differential equations for a coupling vibration of a bridge and moving vehicles are derived by means of modal analysis, and are solved by direct numerical integration. Numerical results of time history of dynamic response of concrete slabs and reaction force showed good agreement with field test results.
