混合梁自锚式悬索桥钢混接合段结构形式的对比试验研究

Experimental study of different structure forms of steel-concrete joint section of hybrid self-anchored suspension bridge

广东佛山平胜大桥为我国首座混合梁自锚式悬索桥,钢混接合段是该桥设计的关键技术之一。为确保该桥钢混接合段连接的安全可靠,设计了3种不同结构形式的接合段接头模型,对3种接头模型进行了空间有限元分析和对比模型试验。结果表明:钢混接合段刚度的匀顺过渡可减小应力集中,使传力顺畅;平胜桥钢混接合段设计中对接合面处钢箱梁段作局部加强,对混凝土梁段设置刚度过渡,即采用与本文模型3类似的结构形式比较合理,接合段有足够的承载力;平胜桥钢混接合段采用PBL键连接或采用栓钉连接都是可行的。

Guangdong Foshan Pingsheng Bridge （PSB） was the first self- anchored bridge with hybrid girder in our country. The steel - concrete joint section was one of the key techniques for the design of the bridge. In order to ensure the safety of the steel - concrete joint section of PSB, 3 joint models for the joint section with different structural forms were put forward, and 3D FEM analysis and contrastable model experiments were carried out for the 3 models. The results show that even transition of rigid for the joint section can minish the stress concentration and make the force transfer smoothly; in the design of the steel - concrete joint section of PSB, it is comparative reasonable to strengthen the steel box girder near the joint section locally or set rigid transition parts in the concrete girder, namely, adopt the model No. 3, thus, the joint section has enough beating capability; either PBL shear connectors or studs is applicable for the steel - concrete joint section of PSB.