Life cycle sustainability assessment and optimization of seismic retrofit solutions for RC frame structures

The recent catastrophic seismic hazards have emphasized the crucial need for retrofitting structures built before adopting modern seismic building codes. This study presents a life-cycle sustainability assessment framework to evaluate various seismic retrofit strategies for reinforced concrete (RC) frame structures in earthquake-prone regions. The framework integrates life-cycle economic, social, and environmental domains, alongside seismic safety and functional performance, to enable a holistic decision-making process for identifying the most effective retrofit solution. A non-linear finite element analysis is performed to evaluate the seismic capacity enhancement of various retrofit strategies, including steel jacketing, RC jacketing, and engineered cementitious composite (ECC) jacketing. The proposed cradle-to-grave life cycle assessment reveals that RC jacketing offers the most balanced performance across all impact domains, while ECC jacketing demonstrates strong performance despite challenges related to global warming potential and recycling issues. This integrated approach bridges gaps in the current literature by combining performance-based assessments, life cycle sustainability implications, and multi-criteria decision-making. The findings gained herein offer adaptable guidance for policymakers and stakeholders, paving the way for future research and practices aimed at improving the safety and sustainability of existing structures in high seismic regions.