Analysis on Failure Modes of Light Steel Columns with Different Cross Sections under Fire and Explosion: Fid-Bau Portal

Analysis on Failure Modes of Light Steel Columns with Different Cross Sections under Fire and Explosion

Qi, B. X. / Yan, S. / Zhang, W. X. / Jiang, X. L.

At present, light steel structures for residential buildings are widely constructed. Light steel columns used as important supporting members are often applied in practical engineering. These columns are very sensitive to blast and fire which may occur together. The bottom column failure may lead to progressive collapse of the structure under fire and explosion. In this paper, light steel columns with different sections of H-type, rectangle and round are numerically analyzed to clarify influences of different temperatures and blast loading on the dynamic responses and failure modes. The element model of light steel columns considering high temperature thermal and high strain rate coupling effects is established by finite element software ANSYS/LS-DYNA. Dynamic responses and failure modes of light steel columns are numerically analyzed to develop mechanical behaviors and failure mechanisms. The results show that the light steel column with rectangle section has better capacity under fire and explosion than that of others, and the light steel column with H-section is the weakest among them. The failure modes of light steel columns may be summarized as three types of bending failure, direct shear failure and bending shear combination failure. The relevant research will establish a firm foundation for the analysis method of light steel columns under fire and explosion.