基于非线性累积损伤理论的起重机桁架臂K节点疲劳寿命研究  

Analysis of the Fatigue Life for K-nodes of Crane Based on the Non-linear Cumulative Damage Theory

作　　者：蔡福海[1] 王欣[1] 彭黎 赵福令[1] 

机构地区：[1]大连理工大学,大连116023 [2]常州益利亚重工机械科技有限公司,常州213164

出　　处：《机械科学与技术》2014年第9期1287-1292,共6页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家科技支撑计划项目(20112011BAF04B01);国家质检总局科技项目(2013QK168);江苏省产学研联合创新资金项目(BY2012089)资助

摘　　要：起重机桁架臂焊缝数量多、受力状况复杂,K节点的疲劳寿命采用线性Palmgren-Miner(PM)法则进行计算的精度较差。提出了基于虚拟样机技术的"实测+仿真+比对+统计"组合策略的载荷谱获取方法,可以极大幅度降低实测应力谱的工作量和成本。首次将Huffman非线性累积损伤理论应用于桁架臂K节点疲劳寿命分析,通过设定焊接构件不同的初始损伤,得到了使计算疲劳寿命趋于适度保守的初始损伤建议值。疲劳试验结果表明:此方法比PM法则计算精度更高,由于只需要循环应力-应变曲线和常幅应变寿命曲线等少量的材料性能数据,计算简单,工程应用价值较大。There are large numbers of welds on cranes＇ lattice booms with notably complicated force conditions.The calculation accuracy of fatigue life for the K nodes of crane is low based on the linear Palmgren-Miner（ PM）rule. A new stress spectrum acquisition method named＂measured simulated compared statistics＂integrated strategy of crane K-nodes is proposed based on the virtual prototype technology. The method can reduce the work amount and cost significantly of the spectra acquisition working. The Huffman non-linear cumulative damage theory is applied first time to calculate the fatigue life for the K-nodes of crane. By setting different initial damage conditions,the initial damage suggestion value is proposed that the calculation result of the fatigue life can be moderately conservative. The fatigue test indicates that the calculation accuracy of the non-linear method is higher than the PM rule. As the Huffman non-linear cumulative damage theory requires the cyclic stress-strain curve and the constant amplitude strain-life curve,it could therefore be more suitable for engineering applications.

关 键 词：起重机 桁架臂 K节点 载荷谱 疲劳寿命 非线性累积损伤理论 

分 类 号：TH114[机械工程—机械设计及理论]