Numerical study of dynamic buckling of steel columns subjected to underground explosion

This paper investigates the elastic-plastic dynamic buckling of steel columns subjected to underground explosion. Based on the dynamic response characteristics of columns, dynamic buckling and yielding critical conditions are proposed, and the corresponding critical Peak Particle Velocities (PPV) of ground vibrations are determined for each column. The results obtained from numerical study are compared with the experimental data, and good agreement is observed. Moreover, the effect of slenderness ratio on the dynamic buckling property of the columns is also discussed. The results indicate that the slenderness ratio of column, as expected, also plays an important role in affecting the dynamic response characteristics of columns to strong vertical ground motions. The Peak Particle Velocities of ground vibrations required to causing column buckling increases rapidly with the decrease of slenderness ratio of the column, especially when the slenderness,ratio is small.