Seismic performance of RC buildings: Field lessons, standards and research needs

Based on observations from recent seismic events, many existing RC buildings are at risk of poor performance in future earthquakes. This vulnerability can be attributed to several factors, including deficiencies in the original design methodology, inherent structural irregularities, inadequate detailing, and the significant influence of nonstructural elements on the overall seismic response. Additionally, corrosion plays an important role in seismic response of existing buildings. It substantially affects damage states, failure mechanisms, flexural capacity, and energy dissipation. The reduction of the structural seismic performance of RC structures due to corrosion effects is often associated with the shift in the collapse modality. This work seeks to present a comprehensive overview of the damages observed in recent seismic events, especially due to RC structural irregularities, assessment of the infill walls disposition and the combined effect of corrosion and vertical irregularity impact in RC structures´ seismic response. All this justifies the necessity of continuous refinement of seismic design codes and regulations, considering rigorous yet manageable design guidelines that minimize the potential for misinterpretation and application errors by design professionals.