I型鋼の圧縮局部座屈について

抄録

This paper presents the results of theoretical and experimental investigations into inelastic local buckling of welded built-up I-sections with residual stresses under uniaxial compressive loads. Based on the test results on many speciments and the theoretical calculations, the following important matters were pointed out : 1. A newly developed method, the e-δ^2 method, was proposed to determine the critical strain or load of inelastic buckling from test result. When this new method is applied, the critical strain or load is tangiblly indicated without any difficulties and also much less influenced dy individuality than any other methods. 2. The results of numerical calculation showed good agreement with test results. The theoretical calculation is based on the plastic deformation theory and also the assumption that each element of I-section, web or flange, is regarded as a plate with restraint along its support, and the magnitude of restraint is evaluated by the same way as for elastic buckling. 3. According to the results of experiment presented in this paper, such breadth and thickness ratio of web or flange are much smaller than that indicated by G. Haaijer, that the critical strain attains the strain-hardening range without buckling.