寒冷地区存在大量低温下承受交变荷载的钢结构构件,其发生疲劳破坏的可能性和危害性很大。按目前国内外基于线性累积损伤准则的疲劳分析方法,得出的疲劳寿命随温度降低而增加的结论往往与实际破坏状况不符。为给低温环境下钢结构的疲劳性能研究和疲劳设计提供参考依据,文中对国内外有关低温钢材疲劳性能的试验研究、计算方法以及相应规范进行了综述和分析评价,介绍了断裂力学理论在疲劳寿命评估中的应用,对基于弹塑性断裂力学的低温下疲劳寿命评估研究进行了展望,并探讨了计算机数值仿真技术用于结构疲劳寿命预估的思路和方法。
Fatigue failure has occurred and do occur in steel structure under ahemating load at low temperature. But an opposite conclusion that shows a better fatigue performance at low temperature than that at room temperature could be deduced by analysis method which is based on the principle of linear accumulated damage. In order to provide reference and basis for research on low temperature fatigue behavior and design of steel structure, the review of available literatures is made including the experimental study, calculation method and requirements in Code. The application of fracture mechanics in fatigue life evaluation is concluded. The present study provides that elastic-plastic fracture mechanics and numerical simulation should be used in further study.