Blast-induced Progressive Collapse: Threat-independent or Threat-dependent Approach?

In this study, blast-induced progressive collapse potential is assessed in a 5-story steel moment-resisting frame. Both threat-independent and threat-dependent approaches are considered in this paper. For this purpose, first the frame was analyzed in different threatindependent column removal scenarios using alternate load path method. Then, the model structure is analyzed under different simultaneous blast and column removal scenarios. Affecting parameters such as location of explosive charge, location of initial failure and number of spans are included in numerical modeling. According to results, progressive collapse potential depends meaningfully to column removal approach; threat-dependent approach provides larger structural response. The obtained results provide better insight into the dynamic column removal in blast-loaded framed structures.