城市大跨度人行钢桥主梁结构设计优化研究

Study on the Optimization of the Structure Design of the Main Beam of Urban Long-Span Pedestrian Steel Bridge

在城市大跨度人行钢桥传统设计过程中,通常采用钢桁架或钢箱梁的结构形式,但由于受城市高架桥、立交桥等构筑物的限制,天桥设计时往往因主梁结构高度较高而无法满足要求。论文结合钢桁架及钢箱梁的结构受力特点,提出一种新型的组合结构形式,即采用钢桁架与钢箱组合的结构形式,用钢桁架来替代普通的天桥栏杆,从而达到降低主梁结构高度的目的。通过对比验算分析表明,采用钢桁架—钢箱组合结构既可有效减小人行钢桥的结构高度,同时又能满足人行天桥规范要求。

In the traditional design process of urban long-span pedestrian steel bridge,the structural form of steel truss or steel box girder is usually adopted.However,due to the restrictions of urban viaduct,flyover and other structures,the design of flyover often fails to meet the requirements due to the high height of the main girder structure.Combining with steel truss and the structure characteristics of the steel box girder,this paper puts forward a new kind of composite structure form,that is the sttructural form of steel truss combined with steel box.The steel truss is used to replace the common bridge railing so as to reduce the height of the girder structure.The comparative analysis shows that the combined structure of steel truss and steel box can not only effectively reduce the structural height of pedestrian bridge,but also meet the requirements of pedestrian bridge code.