千米级大跨公铁两用悬索桥结构特性及刚度指标研究

Study on Structure Characteristics and Stiffness Indexes of Thousand-Meter-Scale Road-Rail Suspension Bridges

由于铁路列车活载大、运行速度高及列车运行稳定性和旅客舒适性要求高等特点,高速重载铁路悬索桥技术标准亟待深入研究。对世界各国规范中常用的几种铁路悬索桥刚度评价指标进行分析,并与我国一般桥梁规范中的规定进行对比。对千米级公铁两用悬索桥高速(客车速度200~250 km/h,货车速度120 km/h)、重载(ZH活载,牵引质量5 000,10 000 t)关键技术进行研究。选定主跨为1 196 m的公铁两用悬索桥,通过研究悬索桥不同的支承体系、辅助墩布置方式、高跨比、宽跨比、垂跨比等参数对桥梁竖向刚度、横向刚度的影响,提出适用于千米级公铁两用悬索桥的刚度评价指标及其建议值。提出技术可行,经济合理的大跨度悬索桥方案,并具有良好的横竖向刚度、平顺性和行车舒适度。

Due to the characteristics of heavy train live loads, high speed and high demand for running security and passenger comfort, the technical standards of high-speed and heavy-haul railway suspension bridges need to be further studied. The paper analyzes stiffness evaluation indexes of railway suspension bridges adopted by the codes of various countries in the world, and compares them with the regulations in China’s general bridge codes. The key technologies of the thousand-meter-scale road-rail suspension bridges for high speed(200~250 km/h for passenger trains, 120 km/h for freight trains) and heavy load(ZH live load, traction mass 5 000 t, 10 000 t) are studied. Based on the research on the road-rail suspension bridge with main span of 1 196 m, the influences of different supporting systems, arrangement of auxiliary piers, ratio of height to span, ratio of width to span and ratio of vertical to span on the vertical and lateral stiffness of the bridge are analyzed, and the stiffness evaluation indexes and suggested values for thousand-meter-scale road-rail suspension bridges are proposed. The proposed long-span suspension bridge scheme is technically feasible, economically reasonable, and has good horizontal and vertical stiffness, smoothness and running comfort.