公铁双层矮塔斜拉桥塔区遮蔽效应研究OA

[Objective]This study aims to study the shielding effect of the bridge tower in a double-deck rail-cum-road cable-stayed bridge with low towers.[Methods]Computational fluid dynamics(CFD)was utilized to simulate the wind environment in the tower region.Two critical parameters,namely the wind speed coefficient and the instantaneous wind speed fluctuation rate,were introduced to analyze the wind environment in the tower region under the tower-beam consolidation system and to examine the influence of various bridge tower cross-sections on the wind environment.The results revealed significant differences in the wind environments between the highway and railway tower regions.[Results]The wind environment in the highway tower region was more stable than that in the railway tower region,and the instantaneous wind speed fluctuation rates in both regions exhibited relatively small changes with height.The shielding effect of the bridge tower on the highway bridge deck intensified with increasing height,with lane 3 being the most adversely affected.The wind speed coefficient on the railway bridge deck did not vary significantly with height,and the downline was most impacted by the shielding effect in the tower region,which had a significant impact on driving safety.[Conclusion]In the highway wind environment,rounded bridge towers can mitigate abrupt changes in the wind speed coefficient in the tower region.In the railway wind environment,both rounded and chamfered bridge towers can effectively reduce such abrupt changes in the wind speed coefficient within the tower region.