Simplified model for assessing progressive collapse resistance of reinforced concrete frames under an interior column loss

Abstract

The key to the research of progressive structural collapse is to perform an in-depth investigation into the structural collapse mechanism at the onset of structural component failure due to accidental events and the demand of progressive collapse resistance for the remaining substructures. According to existing research findings, both beams and floors are important anti-progressive structural collapse components. However, the most common available methods for analyzing progressive collapse adopt the empirical coefficient assumption, which lacks the theoretical basis and neglects the contribution of floor resistance. This assumption leads to discrepancies between design and practice and causes unnecessary construction costs. This paper builds the resistance-deformation theoretical framework for the entire progressive collapse of framed structures under an interior column failure scenario based on yield line theory, where the contribution of floor resistance in the structural collapse is taken into consideration. By comparing experimental results to a finite element model, the simplified models are validated from aspects of both experimental and numerical simulations. To further validate the model, a set of beam-slab progressive collapse tests were designed in accordance with the Code for Design of Concrete Structures. Finally, simplified models accounting for floor resistance in the load-carrying and deformation capacities of RC structures to resist progressive collapse were developed to provide a quantitative estimation for practical applications in the design of frame structures.