Abstract
Static loading tests on steel columns and composite columns were carried out in order to investigate basic properties of torsion. Moreover, the results of loading test were compared with theoretical analysis and F.E.M. (Finite Element Method) analysis, considering nonlinear material properties. From the comparative works, following conclusions were obtained. At the test, the failure of steel columns was determined by local buckling. Composite columns had much higher bearing capacity than steel columns because local buckling of steel column was prevented by filled concrete. Torsional moment on yield point and torsional rigidity in the theoretical analysis and the results of F. E. M. analysis had almost corresponded to those of loading tests.
