起重机结构疲劳剩余寿命评估方法研究

Research on Method for Fatigue Life Estimation of Hoisting Machine Structure

针对机械结构的主要破坏形式——疲劳破坏,以桥式起重机焊接箱形主梁为研究对象,根据断裂力学Paris-Erdogan方程,结合Miner疲劳损伤累积理论,应用实验所得数据,推导出疲劳剩余寿命公式。采集不同类型,不同额定起重量起重机一段时间内相应起重量的工作次数数据,以模拟出危险点处相应的载荷谱。以VC++为开发平台,研制完成桥式起重机疲劳剩余寿命评估软件。该软件可模拟实现普通、铸造桥式起重机的疲劳剩余寿命估算,并与实验结果进行比较,表明具有较高的吻合性和实用性。

Aiming at the main destruction form of mechanical structure - - fatigue destruction, taking the welded box girder of a bridge crane as the subject, a formula used to estimate fatigue life was deduced according to Paris-Erdogan equation along with Miner fatigue accumulation theory and the result of fatigue experiment on the welded box girder. Load spectrum of danger points was simulated by collecting the working frequency of different types of cranes in a period time. A kind of software was developed to estimate the fatigue residual life of bridge cranes based on software V ＋＋ Compared with experimental result, it shows that it is of high value in application.