Title: Long-Term and Corrosion Effects on the Punching Shear Resistance of RC Flat Slabs Subjected to Sudden Column Loss

Author(s): Simone Ravasini, Francesca Vecchi, Beatrice Belletti, and Nicolo Bonati

Publication: Symposium Paper

Volume: 357

Issue:

Appears on pages(s): 77-99

Keywords: robustness, reinforced concrete, existing structure, punching, continuous flat slab, long-term effects, corrosion.

DOI: 10.14359/51738761

Date: 4/1/2023

Abstract:
During an extreme event occurring on a reinforced concrete structure, characterized by the loss of a load-bearing element, the remaining resisting members may develop alternate load paths to resist gravity loads. However, it is recognized that reinforced concrete flat slabs are prone to punching shear failure. This issue is particularly relevant for existing reinforced concrete structures where creep, shrinkage, and corrosion effects due to environmental conditions play a fundamental role before the occurrence of the extreme event. In this paper, nonlinear pushdown and dynamic analyses were performed on an existing continuous reinforced concrete flat slab to investigate the structural response in the case of an interior column loss. Firstly, the flexural and membrane action resisting contributions were in-deeply analyzed. Secondly, the crucial effects of creep, shrinkage and corrosion on the dynamic response and punching shear resistance of the system were critically evaluated. Finally, useful insights for the structural robustness assessment of existing RC structures subjected to material deterioration were provided.