Evaluation of the Dynamic Impact of a Passing Vehicle on a Bridge Deck Due to a Damaged Expansion Joint

When a vehicle passes over bridge, it may jump on the bridge due to damaged expansion joint. The sudden induces heavy dynamic impact and therefore damages deck girder. traditional amplification factor defined by current design code shows of static effects bridge. However, only concerns stable moving load induced vehicle. joint sometimes exceeds allowable load, so is important evaluate in practice. In fact, can be approximately considered as contact force between damped harmonic oscillator beam bilateral symmetry vehicle; therefore, model-based approach using midspan acceleration proposed this study force, where assumed an exponentially sine function. This typical parametric inverse problem. conjugate direction method used determine unknown parameters initial values are determined simple global search method. Since five included, simpler than conventional basis function-based methods. Numerical simulations were conducted validate Generally, performs well identify impact. particular, displacement measured directly from preferred since obtained has numerical errors; measurement noise range 1% 5% slight influence method; error frequencies mode shapes greatly affects method, especially for maximum force.