보-기둥 접합부에서 강섬유보강 콘크리트의 효율성에 관한 연구

Abstract

For the sufficient strength and ductile behavior of RC beam-column joints, closely-spaced lateral confinement reinforcement is required by seismic design codes. However, such seismic design often hinders the economic efficiency and constructability of a structure. The use of steel fibers in RC beam-column joints can improve the cost effectiveness and overcome fabrication complications, such as congested reinforcement details and associated poor concrete placement, without altering its seismic performance. To investigate the effect of steel fibers in RC beam-column joints, an experimental study was carried out under seismic loading conditions. A total of six half-scale joint specimens with seismic details or replacing steel fibers were subjected to three reversed cycles at each drift level up to 6% lateral drift ratio. The variables studied in this investigation are the joint transverse reinforcement amount and steel fiber volume fraction (0, 1, and 1.5%). The results of tests show that lateral load capacity, energy dissipation capacity, shear strength and ductility, and drift capacity are improved with the application of steel fibers of 1.5% but with the same configuration for the rest of the details. Also, a detailed analysis of both global and local data reveals the possibility of substituting steel fibers for some of the transverse reinforcement