基于顺序法的起重机疲劳寿命预测方法研究及应用

摘要

Considering the situation that cranes are generally in service under the random cyclic load and bear cyclic alternating stress, the paper puts forward a life prediction method for crane based on sequential method, with establishment of the order cyclic damage stress model. According to the measured stress process data of the crane, the number of stress cycles is figured out by the rain-flow counting method, with the cycle times corresponding to different stress amplitudes obtained , and with a cyclic loading spectrum developed. Based on this spectrum, the crane life is estimated using the order cyelic damage stress model. The estimated result and the one worked out based on Miner lodel and Carten-Dolan model are compared and analyzed, which shows that the proposed order cyclic damage stress model is feasible for prediction of crane's fatigue life, providing a new idea for research on crane's fatigue life.%针对起重机一般作业于随机循环载荷下,承受循环交变应力的实际情况,提出了基于顺序法的起重机寿命预测方法,建立了起重机顺序循环应力损伤模型.根据起重机实测应力历程数据,利用雨流计数法统计出应力循环次数,获得不同应力幅对应的循环次数并编制循环载荷谱,再根据编制的载荷谱利用顺序循环应力损伤模型对该起重机进行寿命估算.将估算结果与根据Miner模型、Carten-Dolan模型的估算结果进行对比分析.对比分析表明:所提出的顺序循环应力损伤模型对起重机疲劳寿命预测是可行的,为起重机疲劳寿命预测研究提供了一种新的思路.