Buffeting-Induced Fatigue Damage Assessment of a Long-Span Bridge under a Changing Climate Scenario

Abstract

With the continuous increase of bridge spans, wind-induced vibrations will pose serious problems to structural integrity and serviceability. Among the many vibration sources of long-span bridges, buffeting, which results from impinging turbulence, affects the fatigue life of the bridge structure, and when coupled with other wind-induced loads, might lead to severe structural problems. With climate change, buffeting-induced fatigue might significantly increase due to higher wind speeds and turbulence intensities. Therefore, it is important to assess the cumulative fatigue damage generated by buffeting loads under changing climate scenarios. In this study, the buffeting response of a single-span suspension bridge is investigated in the frequency domain under the Worst-case climate scenario RCP8.5. A simplified bridge model will be used to capture key dynamic and aerodynamic characteristics, with a time-dependent Weibull distribution accounting for nonstationarity in wind speed. The analysis of fatigue damage accumulation under buffeting will involve the rain-flow cycle counting method and the Palmgren–Miner damage law. Three Canadian cities, Montreal, Toronto, and Vancouver, will be included in the study to assess how location, along with the climate scenario, influences the life-cycle buffeting-induced accumulated damage over a 100-year period.