针对矩形截面刚架结构极限承载力分析中存在的问题，本研究通过控制性内力 分析遴选了合适的矩形截面广义屈服函数，通过齐次化后建立了矩形截面刚架结构极限 承载力分析的弹性模量缩减法． 首先，根据回归分析和拟合误差分析建立了等效齐次广义 屈服函数; 其次，利用齐次广义屈服函数定义单元承载比，通过有策略地缩减高承载单元 弹性模量模拟结构刚度退化，进而通过线弹性迭代分析确定矩形截面刚架结构的极限承 载力; 最后，根据内力占比研究了平面及空间受力刚架的控制性内力，通过对比分析遴选 确定了合理的齐次广义屈服函数，并验证了本研究提出的方法的计算精度和效率． 结果表 明: 本研究提出的方法作为线弹性迭代方法具有很高的计算精度，且克服了传统的非线性 迭代方法的缺陷，能够取得更高的计算效率．

In order to solve the problems in the ultimate bearing capacity analysis of steel frames with rectangular sections，an appropriate generalized yield function of rectangular cross-section was selected through the control internal force analysis，and then the elastic modulus reduction method for the analysis of the ultimate bearing capacity of rectangular cross-section rigid frame structure was established through the homogenization． Firstly，the equivalent homogeneous generalized yield function was established based on regression analysis and fitting error analysis． Secondly，the element bearing ratio were defined based on the homogeneous generalized yield function，then，the elastic modulus reduction method was proposed for determining the ultimate bearing capacity of steel frame by strategically reducing the elastic modulus of the highly stressed elements to simulate the structural stiffness damage． Finally，the key internal forces of the plane and space steel frames were investigated by means of determining the internal force ratios，further，an exact homogeneous generalized yield function was determined，and the accuracy and efficiency of the proposed method was verified． The results show that the proposed method as a linear elastic iterative method has high accuracy and overcomes the limitations of the traditional nonlinear iterative method，which can achieve higher computational efficiency．