Abstract:In order to investigate the antiblast performance of Hsection steel columns at blast and prefabricated fragments, the damage effect of the combined blast and fragments loads on the Hsection steel column is simulated by arranging the prefabricated fragments around the cylindrical TNT based on the nonlinear finite element software ANSYS / LSDYNA .The difference of dynamic response of Hsection steel columns at blast load, fragments load, and combined blast and fragments load is analyzed. Meanwhile, the influence of axial compression ratio, steel strength, slenderness ratio, and cross section type on the dynamic response of the steel column at combined blast and fragments load is investigated by using the parametric analysis method. The research indicates that the combined effect of blast and prefabricated fragments under adjacent explosion has a superposition enhancement effect and the combined load is bigger than the linear superposition of single load effect. In the antiblast design of steel columns, the value of the axial pressure should be controlled, and when the steel strength grade is Q235 the axial compression ratio should not be bigger than 0.4. It is reasonable to choose steel strength instead of blindly choosing highstrength steel. By changing the column height to change the slenderness has little effect on the steel column. Tubular crosssection steel column has the best antiblast ability, followed by Hsection and box section.