铁路钢筋混凝土低高度梁刚度加固分析

既有铁路合九线跨度为8.0 m的钢筋混凝土低高度梁由于梁体挠度超限、竖向刚度不足的问题,影响到该铁路线的列车提速运营。为提高该类桥梁的竖向刚度,拟采用施加体外预应力和贴钢板的方案进行梁体加固。文中采用有限元方法并结合现场实测数据研究了该低高度梁加固前后的挠度、频率等参数的变化情况,对两种不同加固方案的加固效果进行了分析比较,为同类低高度梁的刚度加固措施提供参考。

Stiffness Strengthening Analysis of Railway Bridges with Low-Height Reinforced Concrete Beams

The low-height reinforced concrete beams of Hefei-Jiujiang Railway with span 8.0 m are often faced with the problems such as the middle-span deflection exceeds the limit and the vertical rigidity is insufficient,which will impact on the speedup of the railway.In order to improve the vertical rigidity of this kind of bridges,the proposal of pasting steel plates and exerting external prestress was suggested to be adopted.The change of deflection and frequency resulting from the strengthening was studied by FEM analysis and measured data.The research provided a full assessment of stiffness strengthening effect about this two methods,and it provides reference for the stiffness strengthening project about low-height reinforced concrete beams of the same kind.