重载铁路混凝土梁常见病害分析及处理对策研究

Analysis and Treatment of Common Concrete Beam Damages of Heavy Haul Railway

以朔黄铁路近2000孔混凝土梁为研究对象,开展重载运输对既有铁路混凝土梁的影响分析、常见病害统计及原因分析,并提出相应的加固处理对策。结果表明:重载运输导致桥梁结构主梁、墩台基础、支座等结构横向、竖向和纵向受力大幅增加,活载储备量降低,振动和疲劳加剧,进而引起混凝土梁体开裂、挠度过大、横向振动加剧、梁端顶死等一系列病害大量出现并迅速扩展,轴重和运量的大幅提高是病害快速出现和发展的直接原因,通过采取体外预应力加固、辅助钢梁加固和裂缝灌封等措施,可以达到提高混凝土梁结构承载能力、抗裂性能和耐久性能的目的。

With reference to nearly 2000 concrete beams on Shuo-huang Railway, the impact of heavyhaul transportation on the existing railway concrete beams, and the causes of damages are analyzed, andcorresponding countermeasures are proposed. The results show that the heavy haul transportation causesthe horizontal, vertical and longitudinal forces of bridge girder, pier foundation and support structure toincrease significantly, reduces the reservation of live load, exacerbates the vibration and fatigue, andresults in such damages as concrete cracking, heavy deflection and vibration and beam end blocking. Thesubstantial increase of load and traffic volume leads directly to the damages and deteriorations. Thepurpose of improving the bearing capacity, crack resistance and durability of concrete structure can beachieved by means of external prestressed reinforcement, auxiliary steel beam reinforcement and crackencapsulation.