中文摘要：

以沪昆高速铁路长沙段三跨（112＋80＋32）m独塔斜拉桥为研究对象,利用自主研发的车桥耦合振动分析软件TRBF-DYNA开展斜拉桥维修卸索施工期间的桥梁动力响应及列车走行性分析。采用多刚体动力学方法建立31个自由度的车辆模型,采用有限元方法建立轨道—斜拉桥模型,轮轨间竖向采用Hertz非线性接触模拟,横向采用蠕滑理论模拟。分析结果表明：卸索对桥梁刚度的影响不大,对桥梁自振频率的影响在5%以内;卸索期间车致桥梁振动响应略有增加,其中桥面主跨竖向振动位移最大增加了10.8%,但其他参数增幅较小;桥塔以纵向振动为主,不同卸索工况对桥塔纵向振动影响显著;各卸索工况主要影响车辆竖向加速度,对列车其他运行安全性指标影响较小;在卸索期间,列车的行车安全性和平稳性指标均满足规范要求。

英文摘要：

Taking the cable-stayed bridge with single tower and three-span （112＋80＋32） m in Changsha section of Shanghai-Kunming high speed railway as the research object, the dynamic responses of bridge and train running performance during cable removal period were studied with the self-developed software TRBF-DYNA for analyzing vehicle-bridge coupling vibration. The vehicle model with 31 degrees of free- dom was established by multi-rigid-body dynamics method and the track-cable-stayed bridge model was es- tablished by finite element method. The vertical and lateral dynamic interaction between wheels and rail was simulated by Hertz nonlinear contact and creep theory respectively. Analysis results showed that cable removal had little effect on bridge stiffness and the natural frequencies of bridge changed within 5%. The train-induced bridge dynamic response was slightly increased during cable removal. The maximum increase in the vertical vibration displacement of the bridge deck on the main span was 10.8~ but less increase for other parameters. The vibration of bridge tower was mainly the longitudinal vibration and was significantly affected by different conditions of cable removal. Except the vertical acceleration, other running safety in- dexes of train were less affected by cable removal. All the indexes for train running safety and stability met the code requirements during the period of cable removal.