Analysis of Dynamic Response and Current-Carrying Capacity of Bridge-along Cable under Typhoon Load

Abstract

In order to study the structural dynamic response and dynamic load capacity of bridge-along cable under typhoon load, in this paper, the cable under two laying environments, including the steel box girder and steel platform, are taken as the research object. Shiyuan typhoon spectrum and harmonic superposition method are adopted to obtain the wind speed time history curves corresponding to different scales of typhoon wind force, then the wind-induced pulsating displacement of steel box girder and steel platform is calculated by using the wind speed time history curve. The electromagnetic-thermal-structure coupling model is established, and the obtained pulsating displacement under typhoon load is applied to the cable as a boundary condition to obtain its dynamic response characteristics. The eccentricity of XLPE insulation is used as the evaluation index of the current-carrying capacity of cable under different scales of typhoon wind force and different laying environments. The simulation results show that the maximum stress amplitude on the metal layer occurs near the clamp during cables are forced to move under typhoon load. The higher the typhoon wind force, the lower the allowable current-carrying capacity. Under wind force 10, the current-carrying capacity is not affected by the typhoon weather; under wind force 11, the current-carrying capacity dropped by 17.2%; under wind force 12, the current-carrying capacity dropped by 47.7%; under wind force 13, the cables are not recommended to work. The research results provide theoretical guidance for assessing the power supply reliability of bridge-along cables under typhoon disasters.