许沟特大桥主拱结构徐变与收缩影响研究  

Study on Creep and Shrinkage of Concrete in Xugou Bridge

作　　者：姬同庚[1] 张锋 张永水[3] 

机构地区：[1]北京科技大学,北京100083 [2]河南扶项高速公路有限公司,河南周口466000 [3]重庆交通学院,重庆400074

出　　处：《公路交通科技》2006年第6期77-80,共4页Journal of Highway and Transportation Research and Development

摘　　要：针对许沟特大桥主跨220 m钢筋混凝土等截面悬链线箱形无铰拱,主拱圈采用支架上分层分段现浇施工方法属国内首创,混凝土徐变与收缩对主拱受力影响很大。通过建立合理的徐变与收缩数学模型和采用数值及有限元分析方法,研究了各加载工况下混凝土徐变、收缩对主拱主控截面内力与变形以及截面应力重分布的影响,分析了混凝土收缩对主拱圈分层浇注自应力的影响。研究结果为大桥预拱度设置及分段分层浇注方案制定和时间间隔控制提供了可靠的理论依据,并为同类桥梁的设计、施工提供借鉴指导。With reference to the 220 m hingeless reinforced concrete catenary box arch main span of Xugou bridge, the construction method of casting concrete for the arch ring in situ in layers and segments is presented for the first time in China.The effects of the creep and shrinkage of concrete on the ring are very large. Through building the mathematical model of concrete creep and shrinkage and using maths and limited element analysis method, the influences of the creep and shrinkage of concrete on the inner force, deformation and stress redistribution of the ring are studied, and the effects of shrinkage of concrete on self-stress of casting in layers are analysed too, Based on the results, the bridge ring camber setting and casting plan ＆ time interval control are determined.

关 键 词：大跨度钢筋混凝土箱形拱 混凝土收缩与徐变 应力重分布 自应力 

分 类 号：U448.223[建筑科学—桥梁与隧道工程]