基于随机有限元法分析塔机动载荷下的疲劳可靠性  

FATIGUE RELIABILITY ANALYSIS OF TOWER CRANE UNDER DYNAMIC LOADS BASE ON STOCHASTIC FINITE ELEMENT METHOD

作　　者：郭茫茫 杨静[1] 王宇佳 韦疆宇 GUO MangMang;YANG Jing;WANG YuJia;WEI JiangYu(Xi'an University of Technology,Xi'an 710048,China;China Construction First Building (Group)Corporation Limited,Beijing 100061,China)

机构地区：[1]西安理工大学机械与精密仪器工程学院,西安710048 [2]中国建筑一局(集团)有限公司,北京100061

出　　处：《机械强度》2018年第6期1389-1394,共6页Journal of Mechanical Strength

基　　金：陕西省科学技术研究发展计划(2014TG-01);西安市科技计划项目(2017080CG/RC043(XALG036))资助~~

摘　　要：为了计算塔机在随机动载荷作用下的疲劳可靠度,考虑影响塔机可靠度的各输入参数的分布,如塔机动载荷参数的分布,采用随机有限元法得到各疲劳校核点的应力-时间历程,经雨流计数得到应力谱,基于Miner线性疲劳累积损伤理论计算其剩余强度;考虑到塔机结构的复杂性,无法得到其结构可靠性功能函数的显式表达,基于应力-强度干涉理论,采用随机有限元法对塔机的疲劳可靠度进行计算,得到了塔机各年份的可靠度,并对超载对可靠度的影响进行了定量分析,结果表明可靠度随使用年份增加逐渐下降,由于累积疲劳损伤,到一定年份急剧下降;超载对塔机的可靠度影响很大。由于考虑了影响塔机可靠度的各个输入参数的分布,并模拟了塔机工作中的所有可能工作情况,因此结果比现有方法更与实际相符,可以为塔机的疲劳可靠性评估提供参考。In order to calculate the fatigue reliability of tower crane under random dynamic loads,this paper consider the distribution of the input parameters affect the tower crane reliability,such as distribution of maneuver load parameters,using stochastic finite element method to calculate stress-time history of tower crane fatigue check points,using rain flow counting method to get the load spectrum of the check points,the residual strength is calculated based on Miner linear fatigue cumulative damage theory.Considering the complexity of the structure of tower crane,it is unable to get the explicit expression of the reliability function.Based on stress-strength interference theory,this paper uses stochastic finite element method to calculate the tower crane reliability,and.the influence of overload on reliability is analyzed quantitatively.The results show that with the use of tower crane,its reliability decreased gradually and due to the cumulative fatigue damage there is a sharp decline of the reliability after a certain period of time,and overload has a great effect to the tower crane reliability.Due to the distribution of all input parameters influence the reliability of the tower crane were considered,and all possible conditions in the work of the tower crane were simulated,the results are more consistent with the actual than existing methods,which can provide reference for the evaluation of fatigue reliability of tower crane.

关 键 词：塔式起重机 分布参数 应力谱 疲劳可靠度 随机有限元 

分 类 号：TH122[机械工程—机械设计及理论]