横撑布置对钢结构拱桥地震响应的影响研究

Study on the influence of the lateral brace arrangement on the seismic response of steel structure arch bridges

以一座地震区钢结构拱桥为研究背景,设计了横撑在拱顶处交叉布置,在1/4拱肋处交叉布置及在1/4拱肋处平行布置三种不同方案。首先进行模态分析,然后采用非线性时程分析对其地震响应进行研究。研究结果表明:横撑在拱顶处交叉布置能够更好的降低纵向地震作用力下拱肋的内力,横撑在1/4拱肋处平行布置能够降低横向地震作用力下拱肋的轴力,总体而言,横撑在拱顶处交叉布置能够更大限度的降低拱肋的内力响应。

Taking the steel structure arch bridge in a seismic area as the research background, three different schemes of cross bracing arranged at the vault, intersecting at the 1/4 areh rib and parallel arrangement at the 1/4 arch rib are designed. First, modal analysis was performed, and then nonlinear seismic analysis was used to study its seismic response. The results show- that the cross bracing at the vault can better reduce the internal force of the arch rib under the longitudinal earthquake force. The parallel bracing at the quarter arch rib can reduce the axial force of the arch rib under the lateral seismic force. In general, the cross struts arranged at the vaults can have a greater limit to reduce the internal force response of the arch ribs.