根据广义屈服准则定义了杆系和板壳结构的单元承载比,建立了承载比均匀度和基准承载比的计算表达式,然后通过弹性有限元迭代分析系统地缩减高承载比单元的弹性模量,使得结构中的单元承载比逐渐缩减,进而求得极限荷载下限,从而建立了以单元承载比为控制参数的弹性模量缩减法,并应用于构件截面几何尺寸或材料性能不同的复杂结构的极限承载力分析中,扩大了弹性模量调整法的应用范围。利用该方法计算了梁、刚架、桁架、板和壳等结构的极限承载力,并分析了结构的失效模式和影响因素。通过和弹塑性增量法的比较,证明了弹性模量缩减法具有较强的适应性、较高的计算精度和计算效率。 According to the generalized yield criterion, the unit bearing ratio of the rod system and the plate shell structure is defined, and the calculation expression of the bearing ratio uniformity and the reference bearing ratio is established. Then the elastic finite element iterative analysis system is used to reduce the elastic modulus , So that the unit bearing ratio in the structure is gradually reduced, and then the lower limit of the ultimate load is obtained. Thus, the elastic modulus reduction method with the unit bearing ratio as the control parameter is established and applied to the complicated structures with different cross-sectional geometric dimensions or material properties In the analysis of ultimate bearing capacity, the application range of elastic modulus adjustment method is expanded. Using this method, the ultimate bearing capacity of beams, rigid frames, truss, slab and shell structures was calculated and the failure modes and influencing factors were analyzed. By comparing with elasto - plastic incremental method, it is proved that the elastic modulus reduction method has strong adaptability, high computational accuracy and computational efficiency.