应变准则在承压设备分析设计中的应用  

Application of Strain Criterion in Design by Analysis of Pressure Retaining Equipment

作　　者：郁杨天 姚志刚 李德知 龙斌 薛飞[1] 陈明亚[1] 余伟炜[1] 师金华 YU Yang -fian;YAO Zhi -gang;LI De -zhi;LONG Bin;XUE Fei;CHEN Ming - ya;YU Wei - wei;SHI Jin - hua(Suzhou Nuclear Power Research Institute Co.,Ltd.,Suzhou 215004,China;Yangjiang Nuclear Power Co.,Ltd.,Yangjiang 529941,China)

机构地区：[1]苏州热工研究院有限公司,江苏苏州215004 [2]阳江核电有限公司,广东阳江529941

出　　处：《压力容器》2018年第6期31-35,共5页Pressure Vessel Technology

基　　金：国家自然科学基金项目(51435012);江苏省自然科学基金项目(BK20150280;BK20171223);江苏核能源装备材料工程重点实验室开放性研究基金项目(NJ20170012)

摘　　要：介绍了分析设计中的应力分类法和弹塑性应力分析方法(直接法),应力分类法仅适用于简单荷载作用下、简单结构的分析设计和校核。与直接法中的两倍斜率等判据相比,应变准则避免了选择变形点位置绘制荷载-变形曲线等潜在人因误差,各国标准也趋于使用应变准则判据。以某核电厂使用膨胀节为例,根据应力分类等准则确定了结构的极限荷载(C_L),并依据应变准则计算了塑性失稳荷载(C_I)。研究案例中,直接法计算的C_L比应力分类法高75%以上;最大应变0.5%准则法简单易行,且其结果与零曲率点法结果一致;依据5%应变准则法更容易获取C_I,且可以使结构的极限荷载提高97.3%。The stress classification method and elastic-plastic stress analysis method （direct method） in design by analysis were introduced. The stress classification method is only applicable to the design by analysis and check of uncomplicated structures under single loads. Compared with the double slope criterion in the direct method, the strain criterion method avoids the potential human errors, such as selecting the location of deformation points to plot the load-deformation curves, and the codes of various countries also tend to use the strain criterion method. Take the expansion joint of a nuclear power plant as an exam- ple, the limit load （ CL ） of its structure was determined according to the criterion like the stress classifica- tion, etc., and plastic instability load （CI） was calculated according to the strain criterion. In the research cases, CL calculated by the direct method is more than 75% higher than that by the stress classification method ; The maximum strain 0.5 % criterion method is simple and easy to operate, and the result is in agreement with the result by the zero curvature point method ;it is easier to obtain CI according to the 5%strain criterion method and the limit load of the structure can be increased by 97.3 %.

关 键 词：应力分类法 弹塑性应力分析方法 应变准则 有限元分析 膨胀节 

分 类 号：TH49[机械工程—机械制造及自动化] TL351.6[核科学技术—核技术及应用]