Numerical Analysis of Structural Behavior and Damage Mechanisms in Shear-Deficient Reinforced Concrete Columns Retrofitted with RC Jacketing

Designing reinforced concrete columns in adherence to earthquake-resistant design principles and ensuring proper implementation during construction are crucial factors influencing the seismic performance of reinforced concrete structures. Following the extensive damage observed in columns of reinforced concrete buildings during the February 6th Kahramanmaraş (Türkiye) earthquakes, this study aims to investigate the underlying causes of these failures. The analysis first examines the observed damages from the perspective of earthquake engineering and structural mechanics. To further investigate, numerical analyses were conducted using a representative reinforced concrete building model. Three structural models were considered: a reference model and two variations with strengthened elements. The reference model utilized C8/10 concrete with S220 reinforcement, with transverse reinforcement spacing of 300 mm. For this model, reinforced concrete jacketing was proposed as a strengthening method for elements exceeding their shear force capacity. Shear-deficient columns were identified, and the jacketing technique was applied incrementally—first to a single column and subsequently to all columns within the structure. Comparisons of the limit and demand shear forces across the three models demonstrated that reinforced concrete jacketing significantly enhanced the shear force capacity of the structural elements, providing an effective solution for improving seismic performance.