Assessment of Different Methods for Enhancing Progressive Collapse Resistance of Irregular Reinforced Concrete Buildings Using Pushdown Analysis

Abstract

AbstractEnsuring structures meet rigorous structural requirements is paramount in mitigating progressive collapse risk. In this comprehensive investigation, we scrutinize the impact of four distinct mitigation techniques on the propensity for progressive collapse in a six-story building featuring irregular structural attributes. The study adheres to the concrete building construction code ACI 318-14 and evaluates methods that include: (a) reinforcing the reinforced concrete (RC) slab with high-performance fiber-reinforced cementitious composites (HPFRCCs), (b) enhancing the RC slab with carbon fiber-reinforced polymers (CFRPs), (c) incorporating steel plate shear wall (SPSW) within specific columns, and (d) introducing an innovative approach named as the steel belt strip (SBS). In the context of 10 independent column loss scenarios conducted on the first floor, the nonlinear dynamic analysis reveals that HPFRCC effectively reduces vertical displacement under the removed column by up to 99.89% in certain scenarios. Meanwhile, the use of CFRP layers leads to reductions of up to 95% in vertical displacement, but with variations in effectiveness across scenarios. Notably, the SBS technique demonstrates remarkable potential by reducing vertical displacement by 97%, 89%, and 25.9% in different scenarios. This reduction, in conjunction with the mitigation of axial load on adjacent columns, makes the SBS a standout performer. Moreover, pushdown analysis indicates that, with the employment of these mitigation methods, the maximum loading factor can be increased up to 2.14 times in specific scenarios, significantly enhancing the structure’s resistance to progressive collapse. This pioneering research not only bolsters the resilience of irregular RC buildings but also holds profound implications for industry standards, risk assessment, and construction technology innovation.