en سازه Body structure پژوهشي Research Thin-walled columns are frequently employed in vehicle structures to diminish the damages resulting from vehicle collisions. In this research, the effect of hole shapes and dimensions on crushing behavior of octagonal multi-cell columns subjected to longitudinal loading is studied. Rectangular, hexagonal and elliptical holes are assumed on the octagonal multi-cell columns, and crushing parameters (i.e. specific energy absorption <em>SEA</em> and maximum crushing force <em>F_max</em>) are then obtained by performing numerical analyses in LS-DYNA. The results demonstrate that creation of holes on column walls improve crushing capability significantly, such that creation of rectangular, hexagonal and elliptical holes on the octagonal multi-cell columns increases the value of <em>SEA</em> by 37%, 42% and 39%, respectively in comparison to the plain octagonal column. On the other hand, presence of holes on the octagonal columns results in reduction of <em>F</em>_max (as a negative crushing indicator).<br> <br> &nbsp; Thin-walled columns, Crushing capability, Hole shape, Octagonal multi-cell column 3534 3546 http://ase.iust.ac.ir/browse.php?a_code=A-10-323-1&slc_lang=en&sid=1 Sadjad Pirmohammad s_pirmohammad@uma.ac.ir 180031947532846003420 180031947532846003420 Yes Mechanical Engineering Department, Faculty of Engineering, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran. Sobhan Esmaeili Marzdashti sobhanesmaeili90@gmail.com 180031947532846003421 180031947532846003421 No Mechanical Engineering Department, Faculty of Engineering, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran. Elnaz Vosoghifard Vosoghifard.el@gmail.com 180031947532846003422 180031947532846003422 No Mechanical Engineering Department, Faculty of Engineering, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran.