Abstract
The deformation of wide flange sections subjected to a normal compressive force and bending moments in the elasto plastic range is studied with an assumption that the flange is concentrated in its gravity centre. An illustrative result obtained through a numerical integration by a computer is given in two charts, which may be correspond to the modified slope deflection coefficients. Then the effects of the cross sectional shape and of the yield strength in materials are discussed with those coefficients. Finally the design criterion of columns unrestricted to side sway is roughly estimated with elasto-plastic deformation characteristics and is compared with the AISC design formula for the plastic design. It may be found that there is afair coincidence between those criteria.
