The influence of steel corrosion on the seismic performance of RC heritage structures: The Stadio Flaminio in Rome case study

The Stadio Flaminio is a remarkable Reinforced Concrete (RC) sport facility designed in the late 1950’s by Pier Luigi and Antonio Nervi for which a conservation plan was recently developed by one of the Authors. In this context, a Finite Element (FE) linear model of the entire structure was developed for a preliminary assessment of the structural capacity. Due to its significance as modern heritage asset, the Flaminio has recently undergone extensive studies and experimental investigations including in situ material properties testing, 3D massive survey, and ambient vibration measurements. In this context, detailed in-situ deterioration survey was carried out revealing signs of reinforcement corrosion in some structural elements. This study investigates the effects of this detrimental phenomenon on the seismic performance of the structure, aiming to raise awareness on its current status and its potential evolution. To this end, advanced nonlinear modelling techniques are used to perform pushover analyses of the East Grandstand frames. Specifically, the complex geometry of the frames and nine corrosion scenarios with different spatial patterns and deterioration intensities are modeled in detail by a fiber-based approach. The analyses show that, in the scenario which approximates the current corrosion state, the structure has a residual capacity essentially equivalent to the undamaged one. However, the other scenarios studied as possible evolutions of the present deterioration state may produce, at high corrosion intensity, significant reductions in capacity both in terms of strength and ductility.