Collapse Distribution Scenario in Seismic Progressive Collapse of RC Buildings Caused by Internal Column Elimination

Prediction of the safety margin in the buildings against the progressive collapse mechanism due to the earthquake loads is a significant issue in the structural and earthquake engineering. In this paper, modeling of the collapse distribution and propagation in the structural elements, one after another, is investigated by tracking down the collapsed locations among the beam and column structural elements in the moment-resisting reinforced concrete short buildings, and the effects of the column removal are studied on the expansion and development of the progressive collapse due to the earthquake loads. A three-story reinforced concrete building designed with ordinary moment frames is modeled, and potential of the progressive collapse mechanism due to the internal column removal is studied using the results of nonlinear time history analyses in the presence of the two-component ground motion records proposed by FEMA_P695. According to the results, some approaches and proposals are presented to seismic optimization of the reinforced concrete short buildings against the progressive collapse mechanism. Also, a collapse distribution pattern is introduced to predict the progressive collapse propagation scenario due to the earthquake loads and the internal column removal.