Transverse free vibrations of continuous bridges with abutment restraint

This paper analyzes the dynamic behaviour of continuous bridges with transverse abutment restraint. These are a particular class of multi-span bridges whose transverse motion is restrained at the abutments. The transverse dynamic behaviour of these partially-restrained bridges is described by a model consisting of a two-dimensional simply-supported beam with intermediate visco-elastic restraints. A minimal set of characteristic problem parameters that completely describe the dynamic response is initially identified and an analytical solution is developed for particular configurations. The influence of these characteristic parameters on the properties of the dynamic systems are analyzed by considering the undamped and the damped free vibrations separately. Successively, in order to cover more general and complex configurations of realistic bridges, an extension of the definition of the characteristic parameters is proposed. The results obtained considering selected case studies are finally presented.