Abstract
The acturl load-deformation curves of steel structural members show sometimes rather different features from that be predicted by simple plastic theory based upon the elasto-plastic stress-strain relation of the material. The role of the strain-hardening is significant in compact sections, and it is important to estimate the true strength of members to secure the unified factor of safety of the structures In this paper, the method of analysis of the ultimate strength of structural members based upon the whole stress-strain relation of the material including the strain-hardening range is presented. In compression members, especially, the new concept on their stability in plastic range seems to be able to develop by the proper evaluation the role of the strain-hardening of the material. The calculation of moment-curvature relationship and curvature integration is readily accomplished by electronic digital computor and be applicable to any practic section
