STABILITY ANALYSIS OF BENDING DAMAGED COLUMNS OF LIGHT-WEIGHT STEEL UNDER ELEVATED TEMPERATURES

The existing damages for lightweight columns due to large deformations such as the results of blast loading might reduce vertical stability as they are exposing themselves to elevated temperatures. In the paper, the stability capacity of a light weight steel column under the condition of various degrees of initial damages is theoretically and numerically researched. The critical stress formula with initial bending damage under elevated temperature was set up by using flexural small deformation condition, and then the stability coefficient was determined and the method for evaluating the limit temperature of the column was put forward. The theoretical result is compared with that of the finite element method (FEM). The results both showed that the stability capacity for the damaged column is dramatically reduced as the temperature increasing. Meanwhile, under the same elevated temperature, the stability capacity will decrease with the increasing of the damage level.