钢腹杆-混凝土新型组合箱拱桥试设计

Trial-design on new-type composite box arch bridge with steel truss webs and concrete flanges

介绍了大跨度混凝土拱桥的发展现状,提出了用钢腹杆代替混凝土箱拱截面中的混凝土腹板,形成钢腹杆混凝土新型组合箱拱桥的构思.介绍了钢桁腹杆混凝土组合结构在梁桥中的应用情况.以主跨160 m的福建宁德岭兜混凝土拱桥为结构原型,进行了钢腹杆混凝土组合拱桥的试设计,并采用有限元方法进行了结构计算分析.结果表明,试设计桥梁满足设计要求且较混凝土拱桥减小拱圈自重约32%.初步研究表明,钢腹杆混凝土组合箱拱通过减轻自重,减小了拱圈内力,有利于悬臂施工,可提高抗震性能,是一种具有应用前景的新型组合拱结构.

Development of concrete arch bridges is introduced. By replacing the concrete webs to steel truss webs, a new-type composite box arch bridge with steel truss webs and concrete flanges is proposed. The application of the prestressed concrete girder bridges with steel truss webs is presented. Taking Lingdou Bridge in Ningde as a prototype, a trial-design of this new type arch bridge is carried out and its structural analysis is performed by finite element method. The results show that the trial design of the new composite arch bridge can meet the design requirement and itseff weight is below 32% compared to the concrete arch ring. The initial researches in this paper indicate that caused by decrease of the serf weight of the arch ring, the internal forces are reduced, and it is a favor to cantilever construction and enhancement of the re-seismic property. Therefore, composite box arch bridge with steel truss webs and concrete flanges is a new type composite bridge which has a good foreground of application in bridge engineering.