Abstract
During 1995 Hyogoken-Nanbu earthquake, many bridges were damaged due to bumping behavior in girders, and which mechanism has been required to be elucidated. This study investigates the damping effect of shock absorbing rubber placed between girders and the modeling of girder-absorber system based on the impedance method. An elastic rod having apparent wave characteristics was employed as the girder model, and which was suspended by steel wires in order to make clear its energy balances in the bumping experiment. It was revealed that the energy losses, which become important for investigating the damping effects of shock absorbing rubber, could be estimated with high accuracy by the impedance method. This method also enables one to estimate the arising stresses at bumping, and confirmed that the bumping stress increases as the length of girder model increases.
