High velocity compressive response of metallic corrugated core sandwich columns

The high velocity compressive response of metallic corrugated core sandwich columns was characterized. One end of a column was compressed, either perpendicular-to-corrugations or parallel-to-corrugations, at a uniform velocity up to 100 m/s whereas the other end was held fixed. Numerical simulations revealed that the response differs from the low velocity response dominated by inertial stabilization; the perpendicular-to-corrugations compressive response was characterized by repetitive densification in a unit cell while the parallel-to-corrugations one occurred during one-way trip of stress wave. The effects of geometric imperfections, column length, compression velocity were investigated through the analysis on rate independent Al6061-T6 corrugated core sandwich columns. On the other hand, the influence of material strain-rate sensitivity was numerically assessed for SS304 corrugated core sandwich columns. As a result, the front end reaction forces increased with imposed velocity while the peak reaction forces on the back end remained invariant. No significant effect of geometric imperfections was observed, and the column length effect was associated with the time scale: the arrival time of stress wave and reaction force variation. Consequently, the analytical expressions for the response were given in terms of sandwich geometric dimensions and loading intensity.