IMPACT ANALYSIS OF CABLE-STAYED BRIDGES

An impact analysis of cable-stayed bridges due to a vehicle moving across rough bridge decks is presented. In the study, the vehicle was simulated by a nonlinear vehicle model with seven degrees of freedom according to the HS20-44 truck. The cable-stayed bridge was modeled as a planar bar system. The road surface roughness of the approach roadways and bridge decks was generated from power spectral density function for very good, good, and average roads according to International Organization for Standardization (ISO) specification. The geometric nonlinearities arising from cable sag and the effect of the axial forces on the stiffness of members were taken into account. The dynamic behavior and impact percentages of these different types of bridges were studied. Furthermore, the influence of damping ratio was discussed. The results obtained are applicable to the design of cable-stayed bridges.