某大跨度钢桥纵向约束体系锚固结构设计与优化

Design and Optimization of Longitudinal Restraint Anchorage Structure in a Long-span Steel Bridge

大跨度钢桥常采用弹性索体系作为大桥的纵向约束,其锚固结构的局部应力较大、传力路径复杂,设计中需要针对其进行专门的计算分析,以保证锚固结构的可靠性。对某大跨度异型拱桥的弹性索锚固结构建立有限元模型,计算分析了钢锚箱结构在最大索力作用下各板件的应力分布。计算结果表明,钢锚箱在最大索力作用下各板件的各项应力值均满足规范要求,结构处于弹性工作状态。同时,针对钢锚箱各板件的布置情况进行优化计算分析,得到合理的锚箱加劲板布置形式。

Flexible cable system is usually used as a longitudinal restraint in long-span steel bridges. Because of the large local stresses and complex load paths, specialized calculation and analysis must be proceeded to ensure the reliability of the anchorage structure in the design. In this dissertation, the finite element model for the anchorage structure of a long-span irregular-shape arch bridge is established to analyze the stress distribution of the steel anchor box under maximum cable force. The results show that the stresses of the steel anchor box under maximum cable force can satisfy the standard requirements and the structure remains in elastic state. The calculation and analysis of the arrangements of each panel of the steel anchor box are optimized and appropriate arrangement of anchor box stiffening plates is obtained.