Evaluation of the response sensitivity of a cable bridge with a seismic isolation to material variation under a near fault earthquake

Several factors can affect the responses of structures under seismic loads. The properties of the materials can be different from the parameters required in the design of the structures. This difference can affect the response of the structures. In this research, it is tried to investigate the effect of changing the characteristics of materials on the seismic response of a suspended cable bridge equipped with a RNC separator whit sensitivity analysis. A cable bridge with and without an RNC isolator has been analyzed dynamically nonlinear after initial modeling under a San Fernando record. Then, the effect of random variables on the response of these structures was investigated using Monte Carlo sensitivity tests and the second-order second moment (FOSM). Finally, the accuracy of the FOSM analysis method is evaluated in a Monte Carlo method. Two basic parameter, maximum deck displacement and maximum base shear was considered as structural responses. The results show that, among the specification of concrete strength materials, the yield stress of the reinforcement and the modulus of elasticity of the cables, the most effect on the seismic response of these structures. Also, the sensitivity of these parameters to the isolated bridge is less than the bridge without isolation.