#cable-stayed bridges

Cable-stayed bridges are bridges that have cables supporting the deck, these cables are all attached to one or more supporting towers, usually in a fan-like shape. While they may look similar, suspension bridges and cable-stayed bridges have quite a few structural differences. Structural design: In a suspension bridge, the main cables are suspended from tall towers and anchored at each end of…

Authored by  Shervin Maleki*

Using spatial cable arrangement to mitigate seismic responses of long cable-stayed bridges is investigated in this study. The innovative cable system strengthens the bridge using cross arrangement of secondary cables. First, a survey on the constructed cable-stayed bridges was performed to establish the dimensions of typical cable-stayed bridges for analyses. Then, a parametric study was carried out in order to achieve appropriate characteristics for the components of the spatial cable system such as, the layout of the cable system, cable effective area and post tensioning forces. Finally, twelve cable-stayed bridges with different cable layouts and main span lengths of 300, 400 and 500 meters were modeled and analyzed. Analyses were carried out using elastic nonlinear direct integration time-history method under six scaled near-fault earthquake ground motion records in the longitudinal and transverse directions, simultaneously. The main purpose of this study is to investigate the effect of supplementary spatial cable system on the seismic performance of cable-stayed bridges. Effectiveness of spatial cross system cable arrangement was assessed by the reduction observed in the seismic responses of the critical parts of the cable-stayed bridges. It was concluded that supplying cable-stayed bridges with spatial cross system cable arrangement decreases the longitudinal seismic response of the deck and it lowers the shear forces and moments in the pylons, especially in longer span cable-stayed bridges.