Seismic performance upgrade of RC frame buildings using precast bolt-connected steel-plate reinforced concrete frame-braces

摘要

This paper presents a new strengthening method for existing frames by using outside sub-structures, namely, precast bolt-connected steel-plate reinforced concrete (PBSPC) frame-braces. The working principles, numerical methods, and design procedures are presented, and case studies are carried out. The simulation results were consistent with the results from previous experiments, indicating the effectiveness of the numerical model. The design objective and procedure were put forward, and during the process, a coefficient 71 that considers the precast influences was considered. A practical engineering retrofitting was performed based on the proposed numerical model and design process, where the structure was subjected to the design basis earthquake (DBE) and maximum considered earthquake (MCE). The analyses demonstrated that the structural demands were clearly reduced within the thresholds, and the inner force was transferred from the existing building to the external substructure after strengthening. The incremental dynamic analysis (IDA) and fragility curves were plotted, illustrating the greater reliability in structural capacity and the lesser possibility of structural damage with the new upgrading form.