نوع مقاله : علمی - پژوهشی
موضوعات
عنوان مقاله English
نویسندگان English
Progressive collapse is a critical challenge for structural performance under abnormal or unforeseen loads. This study evaluates the reliability of multi-story parking structures with special reinforced concrete moment-resisting frames against progressive collapse. Two dimensional models of 3, 6, and 9story structures with uniform 3 meter story heights were developed in ETABS, and key column removal scenarios (corner, edge, and interior) were simulated. Nonlinear static and dynamic analyses assessed collapse probability and member rotation demands. Results indicated that structural sensitivity to column loss increased with height: interior column removal raised collapse probability by 15% in the 3-story, 20% in the 6 story, and 27% in the 9 story structure. Spectral acceleration at instability (Sa) increased by 5% and 8% in the 6 and 9 story models, respectively, compared to the 3-story model, due to higher effective mass and shifts in fundamental period reflecting altered seismic demand with increasing height. Interior column removal proved the most critical scenario, revealing the system's weakness in redistributing loads after losing a central key member. In contrast, corner column removal generated a more balanced load redistribution pattern. Interior columns play a vital role in overall stability, and their loss significantly elevates progressive collapse risk. Therefore, strengthening critical members, incorporating robust lateral load resisting systems, and improving connection design can effectively reduce vulnerability in multi-story parking structures. This study underscores the importance of comprehensive approaches in initial design and retrofitting to enhance structural reliability and mitigate progressive collapse risk
کلیدواژهها English