Fluctuating Wind Field Analysis Of Vehicle-bridge United System Under Crosswinds

The wind resistance ability of the train-bridge coupled system is put under higher demand as the span of the bridge being longer and train speed being higher.To facilitate the analysis wind response of the wind-train-track-bridge coupled system,the current thesis derived a fluctuating wind spectrum model based on Taylor's frozen turbulence hypothesis and isotropic hypothesis.By combining this model of a moving train with that of a static point,a multivariate random process algorithm of the fluctuating wind field of the highspeed vehicle-bridge was established.The main contents are listed as follows:1)Current research status concerning wind spectrum of a moving vehicle and multivariate random process algorithm is summarized together with relevant research methods.The research backgrounds and significances are illustrated.2)Based on Taylor's frozen turbulence hypothesis and isotropic hypothesis,by considering the correlations of different points in the same wind field,the coherence function was adopted to derive a wind spectrum model of a moving vehicle.A parameter study was carried out to evaluate the influence of parameters such as coherence function models as long as the decay parameters and vehicle speed on the wind spectrum.3)A wind tunnel experiment with moving slides was carried out to simulate the wind field of a moving vehicle in wind tunnel conditions.The analytical model was validated by the experimental results.4)A wind field simulation algorithm of the vehicle-bridge united system was established by integrating the wind spectrum of a moving point to the already existed SRM method.The fluctuating wind histories of both the bridge and vehicle was simulated for the scenario of a vehicle operating on a simply supported beam bridge with the total span of 20×32m.