Strengthening of partially ductile RC beam–column connections

Majority of mid-rise RC framed structures are constructed with partially ductile beam–column connections (PDC). Column hoop reinforcement is provided in joint core, however, beam rebars are not fully anchored beyond the face of column. These joints are vulnerable to flexural failure when subjected to reversed cyclic loading. Thus, it is imperative to avoid such situations by strengthening the PDC with a suitable method. A retrofitting technique is proposed in this paper to strengthen such connections or joints. Twelve scaled-down (1:3) specimens comprising 3 types of connection subassemblies are tested. Reversed cyclic loading is applied and performance of these joints is monitored. It is observed that strengthened subassemblies show enhancement in the load-carrying capacity, ductility, cumulative energy dissipation and stiffness. Based on the experimental results, recommendations are proposed for connection strengthening technique. Proposed solution will be useful to strengthen soft storey frames and bare staging frames of an elevated service reservoir (ESR). © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.