Dynamic Responses of Super-Long-Span Suspension Bridge with CFRP Cables under Different Structural Design Parameters

In order to research the dynamic responses of a super-long span suspension bridge with CFRP cables, a super-long-span suspension bridge with CFRP (carbon-fibre reinforced plastic) cables and having a span of 3 500 m was designed by taking a strait as engineering background. Based on the ANSYS software, its dynamic responses and the effects of structural design parameters on the dynamic responses were analyzed. These structural design parameters are rise-span ratio, main cable safety factor, restraint systems of the stiffening girder and bridge tower stiffness. The research results show that torsional-bending frequency ratio increases proportionately with rise-span ratio, and the main cable safety factor has a little effect on the dynamic responses, and a long span decreases the effect of the restraint system of stiffening girder on the dynamic responses and increases the bending stiffness of bridge tower in the axial direction of bridge and the torsional stiffness are benefit to raise the vertical vibration fundamental frequency and torsional vibration fundamental frequency.