Progressive Collapse Mitigation of Hospital Buildings Using Different Retrofit Strategies

Growing global concern about progressive collapse in building structures un-der abnormal loads has driven extensive research on enhancing resistance through advanced design and retrofit solutions. This paper introduces inno-vative retrofit strategies using steel bracing and rooftop outrigger-belt truss systems tailored for hospital buildings. These systems improve vertical stiff-ness and strength with minimal additional mass and sections, enabling rapid, low-impact, and reversible implementation while maintaining uninterrupted building operations during retrofitting. Nonlinear dynamic analyses of real hospital buildings highlight significant improvements in load redistribution and collapse resistance, offering an efficient and sustainable solution for critical infrastructures.