摘要
针对车体设计过程中以确定性模型分析焊点的焊接强度造成的分析结果局限性过大问题,提出了一种基于有限元理论和可靠性理论的焊点强度评估方法.考虑车体的结构尺寸和焊核直径等设计参数的不确定性,采用APDL语言建立参数化的有限元模型.基于AWS C1.1M/C1.1:2012标准编制Tcl脚本文件提取焊点的综合剪切强度,并结合D-最优试验设计,建立焊点强度与设计参数之间的函数关系.在此基础上,运用证据理论计算设计参数的样本点在相应区间的基本可信度分配,并根据可靠性理论进行焊点强度的可靠性分析.结果表明:在设计阶段考虑车体加工制造过程中的不确定性因素,弥补了基于确定性模型相对保守的缺陷,能够更加真实地反映列车的焊点强度;可靠性分析结果可为合理地设计焊点的安全系数提供了理论依据.
Aiming at the problem that the analysis results caused by the welding strength of the welding spot are too large for the deterministic model in the car body design process,a method for evaluating the welding spot strength based on finite element theory and reliability theory is proposed.Considering the uncertainties of design parameters such as structure size and weld nugget diameter of car body,a parameterized finite element model is established by using the APDL language.The comprehensive shear strength of the welding spot is extracted from the Tcl script file based on the AWS C1.1M/C1.1:2012 standard,and combined with D-optimal experimental design,the functional relationship between welding spot strength and design parameters is established.On this basis,the basic probability assignment of sample points for design parameters in corresponding intervals is calculated by using evidence theory,and the reliability analysis of welding spot strength is carried out according to reliability theory.The results show that the uncertainty factors in the car body manufacturing process are considered in the design stage,which makes up for the relatively conservative defects based on the deterministic model,and can more accurately reflect the welding spot strength of the train.The reliability analysis results can provide a theoretical basis for the rational design of the safety factor of welding spot.
作者
智鹏鹏
李永华
陈秉智
ZHI Pengpeng;LI Yonghua;CHEN Bingzhi(School of Mechanical Engineering,Dalian Jiaotong University,Dalian 116028,Liaoning,China;School of Locomotive and Rolling Stock Engineering,Dalian Jiaotong University,Dalian 116028,Liaoning,China)
出处
《中国工程机械学报》
北大核心
2019年第2期159-165,共7页
Chinese Journal of Construction Machinery
基金
国家自然科学基金资助项目(51875073)
辽宁省教育厅科学研究项目(JDL2016001)
辽宁省自然科学基金资助项目(20170540112)
关键词
不锈钢点焊车
不确定性分析
证据理论
焊点强度
stainless steel spot welding car body
uncertainty analysis
evidence theory
welding spot strength
