多主桁空腹拱形桁架钢桥设计

Design of Multi-main Truss Open-web Arched Truss Steel Bridge

摘要:

主要介绍多主桁空腹拱形桁架钢桥结构设计特点。以长春市西安桥改造为工程背景，介绍其总体布置和结构设计，并采用空间有限元程序MIDAS Civil建立总体计算模型，对四主桁下承式简支空腹拱形桁架结构进行了计算分析，研究其空间力学行为。结果表明：四主桁结构受力空间效应明显，空腹拱形桁架整体受力性能和失稳模态均接近于系杆拱。计算分析表明，设计方案合理，多主桁结构满足城市宽幅多车道的桥梁布置要求，为同类型结构设计和方案比较提供了理论依据和实践经验。

Abstract:

The design characteristics of muti-main truss open-web arched truss steel structural bridge are mainly introduced. Taking the reconstruction of Xi'an Bridge in Changchun as the engineering background, its overall layout and structural design are introduced, and the spatial finite element software MIDAS/Civil is used to establish the overall calculation model for the calculation and analysis of four-main truss through simple-supported open-web arched truss structure. Its spatial mechanical behavior is studied. The results show that the force-bearing spatial effect of four-main truss structure is obvious. The overall force-bearing feature and the instability mode of open-web arched truss are close to that of bowstring arch. The calculation and analysis show that the design of this bridge is reasonable, and the multi-main truss structure meets the layout requirements of the urban wide multi-lane bridges, which provides the theoretical basis and practical experience for the design and scheme comparison of the similar structures.