双锚拉板-锚箱索梁锚固结构设计研究及疲劳试验

Design Study and Fatigue Test of Cable-to-Girder Anchorage Structure of Double Tensile Anchor Plates and Anchor Box

铁路斜拉桥索梁锚固结构既承受着恒载索力,又有活载索力长期的反复作用,铁路活载冲击作用大,活载索力所占比重大,且构造复杂,须合理设计以解决疲劳问题。以渝利铁路韩家沱长江大桥为实例,针对铁路钢桁梁斜拉桥索梁锚固区的受力特征与抗疲劳要求,设计研究了一种新型的索梁锚固结构,即整体式双锚拉板-锚箱复合式索梁锚固结构,建立索梁锚固结构板壳有限元分析模型,进行了数值模拟分析,加工制作了1∶1足尺模型并进行了静力加载与动力疲劳试验。分析与试验验证表明,该锚固结构具有较好的受力与抗疲劳性能,在铁路钢桁梁斜拉桥上具有很好的适用性。

The cable-to-girder anchorage structure of railway cable-stayed bridge is not only subjected to the dead load cable forces, but also is acted by the long-term repeated live load cable forces and the impact of the railway live load on the structure is great. As the live load cable forces account for rather great proportion, the anchorage structure is complicated, the structure should be rationally designed so as to surmount the fatigue problem of the structure. In this pa- per, the Hanjiatuo Changjiang River Bridge on Chongqing-Lichuan Railway is cited as an example and in the light of the force condition characteristics and fatigue resistance requirements of the ca- ble-to-girder anchorage zone of the railway steel truss girder cable-stayed bridge, a type of the new cable-to-girder anchorage structure, i.e. the combined structure of the integral double ten- sile anchor plates and anchor box, is designed and studied, the plate and shell finite element mod- el for the structure is established and the numerical simulation analysis of the structure is conduc- ted. The 1 ： 1 full-scale model is fabricated as well and the static loading and dynamic fatigue tes- ting for the structure are carried out. The analysis and testing verification show that the new structure has good force conditions and fatigue resistance performance and is well adaptable to the railway steel truss girder cable-stayed bridge.