高速铁路下承式钢桁结合桥研究

Study of Through Truss Composite Bridges on High Speed Railways

下承式钢桁结合桥跨度大、建筑高度低、刚度大、噪声小、施工快捷,在法国和日本高速铁路上已有应用,我国目前还没有一座这样的桥梁。本文通过有限元分析和模型试验,对下承式钢桁结合桥的结构体系、桥面系结合形式、有限元分析方法、节间长度及纵梁根数对桥面系受力状态的影响、混凝土板裂缝宽度控制等问题作了研究,认为因地制宜地选取下承式钢桁结合桥的合理结构形式用于我国高速铁路建设和既有线提速改造可收到较好的经济效益和社会效益。

Through truss composite bridges have many advantages, such as long span, low construction height, high stiffness, low noise and rapid fabricating. This type of bridges has been used in TGV and high-speed railways of Japan. But there is none in China. Using the finite element method and model test, the structure system, comprising method of the floor system, finite element analysis method, and influence of the panel length and number of stringers on the stress state of the floor system, control of crack widths of slabs are studied. The conclusion is that good economic and social benefits can be obtained if reasonable types of through truss composite bridges are chosen according to local conditions in high-speed railway construction and speed-raising reconstruction of existing lines.