نوع مقاله : مقاله پژوهشی
موضوعات
عنوان مقاله English
نویسنده English
Progressive collapse is a structural failure phenomenon where local damage spreads progressively, leading to partial or total collapse. It has gained attention due to recent incidents under abnormal loads such as impact, explosion, and earthquake. According to the U.S. Department of Defense (DoD) and the Unified Facilities Criteria (UFC), the loss of a column’s load-bearing capacity is a key scenario for evaluating structural behavior under such conditions. In this study, a 9-story steel moment-resisting frame was modeled in three dimensions. Columns were removed at different heights and locations to assess the structure’s response. Nonlinear time-history analyses were performed following the DoD guidelines and the Alternative Path Method (APM) to determine the maximum vertical drift and relate it to the performance levels of plastic hinges. The results indicated that removing a corner column produces the most critical condition, leading to greater deformation and reduced structural capacity. Moreover, removing a column at the top floor resulted in higher vulnerability compared to lower floors. This suggests that as building height increases, the risk of progressive collapse due to sudden column loss becomes more significant. In some cases, especially when removing corner columns at intermediate or upper levels, the structure exceeded life-safety performance criteria.
کلیدواژهها English
