Influence of seismic input characteristics on dissipating devices for bridge structures

The response of a bridge equipped with elasto-plastic dissipating devices to different types of input excitation has been studied through a stochastic analysis. Several input base acceleration time histories have been generated, according to the generalized Kanai-Tajimi model, through a Monte Carlo technique. For each time history parameters characterising the input base motion have been evaluated and correlated to the structural response. Influence of time history duration, frequency content and maximum amplitude on the structural response has been investigated in terms of maximum displacement, maximum force and dissipated energy. The behaviour of the dissipating elato-plastic device is modelled by the hysteretic differential Bouc-Wen model. The model parameters are estimated basing on results of full scale tests on the device.