大跨度上承式钢管混凝土拱桥整体稳定性研究  

Study on Overall Stability of Long-span Deck Concrete-filled Steel Tubular Arch Bridge

作　　者：陈佳[1] 胡文军[2] CHEN Jia;HU Wenjun(Research Institute,China Railway Major Bridge Reconnaissance&Design Institute Co.Ltd.,Wuhan 430056,China;The Second Design Institute,China Railway Major Bridge Reconnaissance&Design Institute Co.Ltd.,Wuhan 430056,China)

机构地区：[1]中铁大桥勘测设计院集团有限公司科研院,武汉430056 [2]中铁大桥勘测设计院集团有限公司第二设计院,武汉430056

出　　处：《铁道建筑》2020年第8期16-19,共4页Railway Engineering

摘　　要：以一座500 m跨度的四线铁路桥梁为例,采用双单元法建立了有限元模型,分析对比了第一类稳定和第二类稳定的安全系数、失稳模态,探讨了初始缺陷、混凝土强度、拱肋截面含钢率等因素对上承式钢管混凝土拱桥稳定性的影响。研究结果表明:结构稳定安全系数满足规范要求,第二类稳定安全系数为2.15,与第一类稳定安全系数之比为1/5.8;第一、二类稳定安全系数的计算结果趋势相同,包含横向风的荷载组合比包含纵向风的荷载组合更为不利;混凝土强度和截面含钢率对结构稳定性能影响较大,初始缺陷则影响很小。Afinite element model was established using the double elements method for a 500 m span four-line railway bridge.The safety factors and instability modes of the first and the second type of stability performance were analyzed and compared,and the influence of initial defects,concrete strength and steel ratio of arch rib section were discussed.The results show that the safety factor of structural stability meets the requirements of the code.The safety factor of the second type is 2.15,and its ratio to the factor of the first type is 1/5.8.The trend of calculation results of the two types of stability safety factors is the same,and the load combination including transverse wind is more unfavorable than that with longitudinal wind.The concrete strength and steel ratio of arch rib section have great influence on the structural stability,while the initial defects have little.

关 键 词：铁路桥梁 结构稳定 理论分析 大跨度钢管混凝土拱 初始缺陷 混凝土强度 截面含钢率 

分 类 号：U448[建筑科学—桥梁与隧道工程]