面内弯矩作用下薄壁弯头的极限载荷估算解  

PLASTIC LIMIT LOAD EQUATIONS OF DEFECT FREE ELBOWS SUBJECTED TO IN-PLANE BENDING MOMENT

作　　者：王辰[1] 王印培[1] 陈进[1] 孙晓明[1] 李培宁[1] 

机构地区：[1]华东理工大学机械与动力工程学院,上海200237

出　　处：《热力发电》2012年第7期57-61,73,共6页Thermal Power Generation

基　　金：国家"十五"重大科技攻关资助项目(2001BA803B03-05);"十一五"科技支撑计划资助项目(2006BAK 02B02)

摘　　要：采用同时考虑材料和几何的非线性三维有限元数值分析技术,分析不同几何参数和不同弯曲模式下配直管连接薄壁弯头的弹塑性行为,研究几何参数和弯曲模式对弯头塑性承载能力的影响规律,获得了相应的极限载荷数值解,并在此基础上建立了极限载荷估算式。分析结果表明,在弯矩作用下,几何非线性对弯头塑性承载的影响显著;弯头在面内开弯载荷作用下的塑性行为与在闭弯载荷下的塑性行为差异很大,其塑性极限载荷值显著不同;弯头壁厚与其横截面半径的比值对弯头塑性承载能力的影响显著,其次为弯曲模式。Elastic-plastic behavior of elbows with various geometric parameters and under various bending modes were investigated by 3-dimensional(3D) non-linear finite element(FE) analysis,assuming material behavior was elastic-perfectly-plastic and taking geometric nonlinearity into account.The influences of geometric parameters and bending mode on plastic carrying capacities were studied systemically,and closed form equations of plastic limit loads for uncracked elbow involving effect of tangent pipes were also obtained.Non-linear finite element(FE) analysis indicates that,the influences of geometric nonlinearity on plastic carrying capacities are significant;elbow exhibits dramatically different behaviors at the elastic-plastic states when subjected to in plane opening bending moment and closing bending moment,and the plastic limit load values are varied obviously under both of the bending modes;the ratio of wall thickness and the cross-section radius is the most significant influence factor on plastic carrying capacities of elbow,followed by the bending mode.

关 键 词：薄壁弯头 极限载荷 面内弯矩 塑性承载 弯曲模式 

分 类 号：U173.2[交通运输工程] TB115[理学—数学]