The Analysis And Discussion Of Flexural-torsional Buckling Of Thin-walled Steel Beam

By means of theoretic analysis and digital imitation, an investigation about the flexural-torsional buckling of thin-walled steel beam is made in this paper.A comprehensive investigation on the two different flexural-torsional buckling of thin-walled steel beam existing in domestic research these days is made .On the base of the general theory of thin-walled members, we deduce a new critical moment formula of steel beam under transverse loads which pass the shear center and parallel to the main axis. By means of ANSYS software, we build the shell model and imitate the flexural-torsional buckling of thin-walled steel beam. We compute the critical moment of steel beam in different span and different site and form of load. Then compare the result of theoretic analysis and digital imitation. Some suggestion are given to the design of stability of steel beam: The numeration of parameter C₁,C₂, C₃ should be adjusted in engineering.On the base of the general theory of thin-walled members, we deduce a critical moment formula of steel beam under transverse loads which deviate the shear center but parallel to the main axis. A validation is carried by the ANSYS software, it indicates that the theoretic result is similar to the digital result. Then the formula is compared with the similar one given by《Technical code of cold-formed thin-walled steel structure》(GB50018-2002) and《Specification for the Design of Cold-Formed Steel Structural》(AISI 96).It indicates that《Technical code of cold-formed thin-walled steel structure》(GB50018-2002) is most conservative.