Progressive collapse resisting capacity of tube-type structures

In this study, the progressive collapse potential of tube-type buildings, such as diagrid and tubular structures, composed of lateral load-resisting perimeter frames and internal pin-connected gravity frames, was evaluated by nonlinear static and dynamic analyses. To this end, 36-and 54-storey structures were designed as analysis models and progressive collapse analyses were carried out by removing first-storey columns. According to the analysis results, the progressive collapse of tube-type analysis model buildings occurred when perimeter columns corresponding to more than 11% of all member cross-sectional areas were removed from one side of the structures. When the diagonals located around a corner were removed, the ratio was reduced to 8%. It was observed that the corner columns in the diagrid system helped prevent the propagation of member failure all around the perimeter.