Buffeting Reliability Analysis of Long-span Cable-stayed Bridges by the First Passage Mechanism

摘要

This paper presents a framework for performing buffeting reliability analysis of the deck system of long-span cable-stayed bridges with different wind directions. The buffeting reliable probability for a specific cross-section of the bridge deck subjected to a strong wind attack is studied by the first passage mechanism with considering the joint probability distribution function of the mean wind velocity and wind directions during the bridge design reference period. Then, the upper and lower bounds of the buffeting reliable probability for the whole bridge deck system of long-span cable-stayed bridges are developed on the basis of the series model. The buffeting reliability of a long-span cable-stayed bridge, with a main span of 628m, is studied for the vertical stiffness of the deck system during its design reference period. It is found that the buffeting reliability of the deck vertical stiffness is decreased with the duration of the mean wind speed.