广西柳州凤凰岭大桥抗震设计

以广西柳州凤凰岭大桥建设工程为例,采用两水平的抗震设计方法,对含有桥上建筑的大跨度连续梁桥在E1、E2地震作用下采用反应谱和非线性时程方法,进行地震反应分析与验算,最终给出结构的抗震性能安全性评价,对该类桥梁的抗震设计提供了有益的参考。

Seismic Design of Phoenix Valley Bridge in Liuzhou, Guangxi

There is a certain diffusion angle for the axial force transfer of the stayed cable in the main girder section of the central-plane concrete cable-stayed bridge, which affects the effective distribution width of the section and cannot be ignored for the design and calculation. The analysis method is studied and determined. The concepts of diffusion length and axial force hysteresis coefficient are introduced. Based on Fengshuba Bridge Project, the axial force hysteresis coefficients of the roof and floor at different diffusion distances are calculated. The transmission law of the axial force of stayed cables in the roof and floor is analyzed, and at the time, the diffusion angle of the axial force of stayed cables in the roof and floor is calculated. In addition, the influence of diaphragm setting on the diffusion angle of cable force is analyzed, which shows that the diffusion angle of axial force of stayed cable in the roof is about 29.3°, the diffusion angle in the floor is about 17.15° and the diffusion velocity of axial force of stayed cable in the roof is 1.71 times of that in the floor. The change of the number of diaphragms of the main girder improves the axial lag coefficient little and has no effect on the diffusion angle.