Optimal seismic retrofitting of reinforced concrete columns with steel jacketing technique: a pushover-based genetic algorithm approach

Steel jacketing (SJ) of columns is widely employed as seismic retrofitting technique to provide additional deformation and strength capacity to existing reinforced concrete (RC) frame structures. The use of SJ is associated with non-negligible costs depending on the amount of structural and non-structural manufacturing and materials. The paper presents an optimization framework aimed at obtaining the optimal increase of seismic capacity/demand performance with minimization of retrofitting costs. It is shown the case study of a 3D RC frame implemented in OpenSEES and handled within the framework of a genetic algorithm. The algorithm iterates geometric and mechanical parameters configuration in order to match the optimal retrofitting solution based on static pushover analysis outcomes. Results of the proposed framework will provide optimized location and amount of steel-jacketing reinforcement, showing that the use of engineering optimization techniques can be effectively used to reduce retrofitting costs substantially unaltering structural safety.