Reduction factors of strength for RC squat infill walls with or without a central square opening due to localized corrosion

Abstract

For typical low-rise reinforced concrete (RC) buildings, which are very common in Taiwan, this work focuses on RC squat infill walls with and without openings. A site investigation revealed localized corrosion near the top of RC infill walls, caused by double curvature and poor concrete quality. This work investigates the mechanical behavior of four RC infill wall specimens with two corrosion zones. Unlike previous approaches, the designed corrosion ratio of the steel bars within the specimens has been increased from 10 % to 15 %. Additionally, this research examines the mechanical behavior of RC infill walls with localized corrosion and a central square opening by designing two specimens with such an opening. An SST model is introduced to determine the ultimate shear strength of an RC infill wall with localized corrosion and a central square opening. Furthermore, the model incorporates considerations for both the mechanical properties of corroded reinforcing steel bars and the concrete softening resulting from corrosion-induced cracks. Finally, this work concludes with strength reduction factors that can be used to estimate the ultimate shear strength of a corrosion-localized RC wall, with or without a central square opening, for preliminary seismic assessments.