混合型自锚式悬索桥连接部位传力研究

The force transmission at the joint of composite self-anchored suspension bridge

某大桥是目前世界上最大跨径的钢与混凝土混合梁自锚式悬索桥,主跨350 m,钢-混结合段是该桥设计的关键技术之一。介绍了目前国内外混合梁主要的结合形式,针对大桥钢-混结合段设计制作了1∶4缩尺模型,并进行有限元分析和试验,研究了钢-混结合段的位移、附近区域的应力分布、结合面处钢与混凝土之间的相对滑移以及混凝土梁表面的裂缝发展。结果表明:钢-混结合段构造合理,刚度过渡平缓匀顺,传力顺畅,结合可靠,有很强的承载力;结合段采用的新型剪力连接件PBL键连接可靠,作用牢固。试验为该桥设计提供了依据,并可为类似设计提供技术储备。

There is a steel and concrete mixed girder self- anchored suspension bridge. Its major span is 350 m which is the largest span of the same type of bridge in the world. The joint between steel and concrete is one of the key of its design. The major types of joint structure in the world is introduced, a 1：4 model was made with numerical analysis and experience. This paper analysis the vertical displacement, the stress, the slippage of the joint, and the development of the crack on the surface of concrete box - girder. The results show that the structure of the joint is reasonable, the stiffness variation is even, the force transmission is smooth, the combination is reliable and capable of bearing heavy weigh. The new type shear connector - perfobond strip workes properly and well. The experiment results provide a basis for the design of the joint, prepares some resourse for the similar design in the future.