Progressive collapse is a catastrophic structural phenomenon that can occur because of natural hazards or human-made like explosive or impulsive loads. In this event, a single local failure may cause a significant deformation which then may lead to the collapse of a structure. In this paper, progressive collapse potential of several five, eight and ten story buildings of steel and reinforced concrete structures which have been designed according to AISC-LRFD and ACI following the removal of an exterior column is evaluated. In addition, an efficient and simply method -based on the beam’s depth to length ratio (D/L)- proposed to prevent progressive collapse of structures. It is shown we can avoid from progressive collapse of steel and RC structures if the depth of the beams around the removed column choose more than L/15 and L/12 respectively
