Identification of a bridge's structural damage and vehicular parameters based on dynamic response sensitivity analysis

Here, both local damages in a bridge's deck and parameters of moving vehicles were identified with a bridge-vehicle coupled system's dynamic responses induced by vehicles moving on the top of the bridge deck. The local damage is simulated by a reduction in the elemental flexural rigidity of the beam. The dynamic model of the bridge-vehicle coupled system was established using the finite element method and the dynamic responses of the system were obtained using Newmark direct integration method. In the inverse analysis, a dynamic response sensitivity-based finite element model updating approach was used to identify both local damages of the bridge deck in element level and parameters of vehicles. The solution was obtained iteratively with the penalty function method and the regularization from the measured structural dynamic responses. A multi-span continuous beam was studied as an numerical example to illustrate the correctness and efficiency of the proposed method. The effects of measurement noise, and measurement time duration on the identification results were investigated. The results indicated that the proposed method is efficient and robust for both damage identification and vehicular parametric identification; good identified results can be obtained with time histories of several measurement points. © 2016, Editorial Office of Journal of Vibration and Shock. All right reserved.