Seismic retrofit of external RC beam–column joints by joint enlargement using prestressed steel angles

摘要: Abstract Reinforced concrete (RC) structures that were built prior to the 1970s generally do not meet current seismic design requirements, especially in terms of reinforcement details. An innovative and practical retrofit method is proposed for non-seismically detailed external beam–column joints existing structures, based on a two-dimensional enlargement joint using steel angles are mounted prestressed cross-ties. Seven half-scale RC subjected lateral cyclic loading increasing amplitudes. The tested specimens comprised three control units four retrofitted units. test results confirmed only resulted relocation beam plastic hinges outside panel zone but also improved bond between longitudinal column tension zone. was shown significantly enhance capacity joints, strength, stiffness, energy dissipation ductility capacity.