摘要
为了研究轴心受压等肢角钢绕截面最小轴弯曲屈曲特性,建立了一种分析方法。基于压杆无应力态下弧长不变原理求得压杆弧长状态方程。在弹性受压阶段,基于压杆中点力矩平衡微分方程求得应力-挠度相关方程。在弹塑性受压阶段,基于角钢压杆中点截面应力分布列出力与力矩平衡方程,从而导出应力-挠度-截面弹性区高度的相关方程;基于压杆中点应变所产生的曲率与轴线函数微分所求得的曲率相等关系求得截面弹性区高度表达式。最后,通过上述基本方程的联立求解,求得角钢压杆在弹性及弹塑性受压阶段的本构关系方程。利用所提出的本构关系方程,研究等肢角钢轴心压杆的屈曲特性。研究结果表明:此方法合理准确,能够有效预测等肢角钢轴心压杆的屈曲特性。
In order to study the flexural buckling properties about minor axis of section for equilateral angle steel under axial compression, an analytic method was proposed. An arc length state equation of strut was established based on the principle that the arc length of unstressed strut should be constant. In elastic compression phase, a dependent equation for stress-deflection was established on the differential equation of moment equilibrium at middle of strut. In elastoplastic compression phase, equilibrium equations of force and moment were listed based on stress distribution at the middle section, and a dependent equation of stress-deflection-section elastic height was derived. An expression of section elastic height was derived based on a relation of equality between the curvature generated by the midpoint strain of the strut and the curvature generated by the differential of axis function. Through the combination solution of fundamental equations, the constitutive relation equations in elastic and elastoplastic compression phases were established. By present constitutive relations of equilateral angle steel strut, its flexural buckling properties were researched. The research results showed that present method was reasonable and accurate, and could predict the buckling properties of equilateral angle steel strut.
作者
陈剑平
林光龙
李文斌
贺启
林俊哲
刘树堂
熊国文
CHEN Jianping;LIN Guanglong;LI Wenbin;HE Qi;LIN Junzhe;LIU Shutang;XIONG Guowen(Jiangmen Power Supply Bureau, Guangdong Power Grid Co. Ltd, Jiangmen 529000, China;Guangdong Power Transmission and Transformation Engineering Co. Ltd, Guangzhou 510160, China;Guangzhou University, Guangzhou 510006, China)
出处
《钢结构》
2019年第3期22-27,68,共7页
Steel Construction
基金
广东电网科技项目(GDKJQQ20161073)
关键词
等肢角钢
轴心受压构件
弯曲屈曲
本构关系
equilateral angle steel
axial compression member
flexural buckling
constitutive relation
