钢桁梁悬索桥整体节点疲劳损伤演化分析

Fatigue Damage Evolution Analysis of Whole Joint of Steel Truss Girder Suspension Bridge

文中依托白洋长江大桥工程项目,针对该桥的疲劳最不利整体节点,通过疲劳试验获取其缩尺模型的疲劳寿命,并根据试验结果推导损伤演化方程.结果表明:单个缩尺模型的疲劳试验结果为42.3万次循环,接近50万次循环的设计寿命,因此实桥整体节点的疲劳性能满足要求.根据试验结果推导的损伤演化方程具有明显的三阶段特征,其持续时间分别占总寿命的10%、85%、5%,产生的损伤分别为20%、30%、50%.与英国规范BS5400计算的理论损伤度相比,具有更好的准确性和经济性.

Based on the project of Baiyang Yangtze River Bridge,the fatigue life of its scale model was obtained through fatigue test,and the damage evolution equation was deduced according to the test results.The results show that the fatigue test result of a single scale model is 423 thousand cycles,which is close to the design life of 500 thousand cycles,so the fatigue performance of the whole joint of the real bridge meets the requirements.The damage evolution equation derived from the test results has obvious three-stage characteristics,the duration of which accounts for 10%,85%and 5%of the total life,and the damage generated is 20%,30%and 50%respectively.Compared with the theoretical damage degree calculated by British standard BS5400,it has better accuracy and economy.