正交异性钢桥面板栓焊接头疲劳性能研究

针对正交异性钢桥面板栓焊连接细节,设计制作两个足尺试验构件,进行了静载、疲劳试验,并建立了有限元计算模型.计算分析发现:纵肋螺栓接头中面外弯矩影响明显,内侧拼接板受力大于外侧;拼接板中纵向应力呈鞍状分布,两个试验构件的疲劳裂纹均在内侧拼接板的中间区域首先出现.建议栓焊接头按Eurocode中的71级或铁路桥梁钢结构设计规范中IX细节进行疲劳设计.通过有限元模拟计算,对拼接板进行优化设计,改善了栓焊接头的疲劳性能.

Fatigue Behaviour of Bolt-Welded Joints for U-Ribs in Orthotropic Steel Bridge Decks

Two orthotropic steel decks with on site bolt welded U rib connection detailing were designed and fabricated. Static and fatigue tests were then conducted. A finite element(FE) model of the bolt welded joints was proposed. The FE analysis showed that the longitudinal stresses on the inner connection plate were larger than those on the outer plate, and the stresses were influenced by the out plane bending in the joints. Stress distributed along the connection plate in saddle like shape. The stresses in the middle region were larger than those in the end, and fatigue cracks appeared earlier in the middle region of the inner connection plate in the both specimens.The fatigue strength of bolted U ribs joint is proposed based on the design curve of category 71 in Eurocode or the design curve of category IX in the Design Code of Steel Railway Bridges. A parameter study was developed to optimize and improve the fatigue performance.