薄板钢构件火灾下的变形能力和承载能力分析

钢结构塑性设计和抗震设计中都要求组成钢结构的板件有足够的局部变形能力,以防止板件局部的屈曲而降低钢板件的承载能力.结合常温状态下钢板件变形和承载能力分析的基本原理和方法,用非线性有限元法,对钢结构中常用的四边支撑钢板件在高温下的屈曲性能进行分析,着重考虑了板件宽厚比、边界约束和初始缺陷等因素对板件变形能力和承载能力的影响.此外,通过参数的分析,还给出了板件宽厚比与变形能力和承载力的相关关系. 

Deformation capability and load-carrying capability of steel plate element under high temperature

In the plastic design and anti-seismic design of steel structures,It is demanded that the component plates undergo large local deformations for the plastic hinge to develop and the load-carrying capability doesn't decrease because of local buckling of the plates.Based on the basic principles and methods which are used to analyze the deformation capability and load-carrying capability of steel plates under normal temperature condition,the nonlinear finite element method was used to analyze the buckling behaviors of four-edge supported plates under uniform uniaxial compression and high temperature.The width-to-thickness ratio,constraint conditions of boundary and initial geometric imperfections were all considered.The relationships among the width-to-thickness ratio,deformation capability and the load-carrying capability were carefully studied.Furthermore,the formulas and the relationships among width-to-thickness ratio,deformation capability and load-carrying capability were also showed according to the parameter analysis,which can be used to evaluate the ductility of steel plates under high temperature.