高震区大跨度上承式CFST拱桥桥面系分联和约束体系研究

Division and constraint system of the bridge deck system of long-span deck CFST arch bridges in high-intensity seismic regions

摘要:

为研究高震区的上承式钢管混凝土拱桥合理的桥面系分联和约束体系,以一座净跨径400 m的公路桥梁为例,采用非线性时程分析方法,对不同分联的桥面系和支座体系下的结构响应进行对比分析。结果表明:1联桥面系显著降低了联端位移及交界墩弯矩,且立柱弯矩均匀;钢支座体系拱顶段和联端剪切力显著增大,交界墩及立柱弯矩较大且分布不均匀;高阻尼橡胶支座体系交界墩及立柱弯矩均显著减小且分布趋于均匀。当采用1联桥面系和高阻尼橡胶支座约束体系时,立柱、支座和交界墩受力协同度高,各构件内力的均值和标准差的差距均显著减小,说明该结构设计的合理性。

Abstract:

This study explores the reasonable division and constraint system of the bridge deck for deck concrete-filled steel tubular arch bridges in high-intensity seismic regions using a highway bridge with a net span of 400 meters. A nonlinear time-history analysis method was applied to compare and analyze the structural responses under various deck systems and bearing systems. The findings reveal that the bridge deck system with one continuous unit significantly reduces the displacement of the unit end and the bending moment of the juncture pier, and the bending moment of columns is uniform. The shear forces at the vault section and unit end of the steel bearing system significantly increase, and the bending moments at the juncture pier and column are large and very uneven. The bending moments at the juncture pier and column of the high-damping rubber bearing system are significantly reduced and tend to be uniform. By using the bridge deck system with one continuous unit and the high-damping rubber bearing constraint system, the column, bearing, and juncture pier have good cooperative force, and the mean value and standard deviation of internal forces for each component are significantly decreased, showing that the structural design is reasonable.