高温下受压钢构件考虑屈曲的有限元本构模型  

CONSTITUTIVE MODEL FOR FINITE ELEMENT ANALYSIS OF STEEL ELEMENTS WITH BUCKLING CONSIDERED AT HIGH TEMPERATURES

作　　者：杨帆[1] 钱稼茹[1] 张微敬[2] 

机构地区：[1]清华大学土木工程系,北京100084 [2]北京工业大学建工学院,北京100124

出　　处：《力学与实践》2010年第6期27-32,共6页Mechanics in Engineering

基　　金：十一五科技支撑计划资助项目(2006BAJ13B03-02)

摘　　要：为计算大空间钢结构高温下的力学性能,需考虑受压钢构件屈曲.将钢构件屈曲特性反映在材料的本构模型中,进行高温下大空间钢结构有限元计算.通过研究轴心受压钢构件在不同温度下的弯曲变形,推导出考虑长细比、初始缺陷、临界力等因素的受压钢构件名义轴向刚度;通过能量等效,用等效刚度代替名义轴向刚度,得到高温下受压钢构件考虑屈曲的钢材两折线应力-应变本构模型,数值计算验证了模型的正确性.In order to study the fire behavior of large space steel structures,the buckling of steel components would be taken into consideration.In this paper,a constitutive model with buckling property of steel component is established for finite element analysis of large space structures at high temperature.By studying the bending deformation of axially loaded steel components at various temperatures,the nominal axial stiffness of the steel components with buckling property is theoretically derived.Influence of slenderness ratio,initial imperfection, and critical load on the nominal axial stiffness is discussed.Using the energy balance method,the nominal axial stiffness is replaced by the equivalent stiffness.Then a bilinear stress-strain constitutive model of steel materials for steel components with buckling property is established.The model is verified by the numerical calculation.

关 键 词：钢构件 屈曲 高温 等效轴向刚度 应力-应变本构模型 

分 类 号：O342[理学—固体力学] TU391[理学—力学]