钢桥腐蚀疲劳的研究现状

Research Status of Corrosion Fatigue of Steel Bridge

钢材由于其良好性能已广泛应用于桥梁结构中,疲劳和腐蚀是钢桥面临的两大问题。在查阅国内外关于钢桥腐蚀疲劳研究基础上,对钢桥腐蚀类型和规律进行了介绍,并阐述了钢桥腐蚀疲劳寿命评估方法和可靠度分析理论。钢桥腐蚀深度与时间存在幂指数关系,点蚀坑形状和尺寸是影响疲劳性能的主要因素;疲劳曲线需要考虑腐蚀损伤的修正,焊接和腐蚀导致的应力集中可以分别通过疲劳缺口系数和腐蚀疲劳缺口系数来表征;为了简化计算,基于断裂力学的腐蚀疲劳寿命预测方法通常将蚀坑等效为形状规则的裂纹或缺口。最后,指出了钢桥腐蚀疲劳未来的研究方向。

Steel has been widely used in bridge structure because of its good performance,fatigue and corrosion are the two major problems faced by steel bridges.Based on the research on corrosion fatigue of steel bridges at home and abroad,the corrosion types and rules of steel bridges are introduced,and the evaluation method of corrosion fatigue life and reliability analysis theory of steel bridges are expounded.There is a power exponential relationship between corrosion depth and time,and the shape and size of pits are the main factors affecting the fatigue performance.The correction of corrosion damage is needed to consider for fatigue curve.The stress concentration caused by welding and corrosion can be characterized by fatigue notch coefficient and corrosion fatigue notch coefficient respectively.In order to simplify the calculation,corrosion fatigue life prediction methods based on fracture mechanics usually equate the pits as cracks or notches with regular shape.Finally,the future research directions of corrosion fatigue of steel bridge are pointed out.