VEHICLE-BRIDGE INTERACTION ANALYSIS: AN UNCOUPLED APPROACH

A formulation of the coupled equations of motion for the bridge-vehicle dynamic interaction problem is proposed. This is based on the assumption that at the bridge-vehicle interface the systems are always in contact and accounts for the pavement roughness. The equations are forcibly uncoupled, moving the coupling terms to the RHS of the equations as forcing terms. The equilibrium condition at the interface is imposed through an iterative solution in the time domain, considering separate and uncoupled mechanical models for the vehicle and the bridge. Two procedures, iterative in principle, are devised: one iterates over the whole time-history and the other over the single time step, making use of a staggered strategy. The former relies on a general purpose FE code for the structure; the latter is implemented in an ad hoc developed code. The numerical studies, performed on a simply supported RC bridge, considering two 3D vehicle models, show the good performance of the two procedures.