aseaThe objective of the rerch reported in this paper was to evaluate the effect of CFRP sheets, externally confining HSC beam-column joints, on the bond strength and ductility of the mode of failure of hooked bars anchored in the HSC joints. To date, there has been no research work in this area. Previous research performed at the AUB indicated a positive contribution of external confinement of FRP sheets to the bond strength of tension lap splices in NSC and HSC beam structures. It was significant to investigate if such an improvement would extend to the bond performance of hooked bar anchorages and the ductility of the failure mode of HSC beam-column connections. Such improvement would encourage the use of CFRP technology in strengthening and retrofitting distressed HSC beam-column joints, especially in earthquake-damaged and blast-damaged reinforced concrete structures.
of the mode of failure of hooked bars anchored in the HSC joints. To date, there has been no research work in this area. Previous research performed at the AUB indicated a positive contribution of external confinement of FRP sheets to the bond strength of tension lap splices in NSC and HSC beam structures. It was significant to investigate if such an improvement would extend to the bond performance of hooked bar anchorages and the ductility of the failure mode of HSC beam-column connections. Such improvement would encourage the use of CFRP technology in strengthening and retrofitting distressed HSC beam-column joints, especially in earthquake-damaged and blast-damaged reinforced concrete structures.
EXPERIMENTAL PROGRAM Twelve full-scale beam-column specimens were constructed and tested using the strong floor-reaction wall testing facility in the Materials Testing Laboratory at the AUB. The specimen simulated the rigid connection of a vertical cantilever beam to a base column. The variables were bar size: 16, 25, or 32 mm (No. 5, No. 8, or No. 10), anchorage mode of the beam bars in the beam-column joint, and whether the beam-column joints were externally confined with CFRP sheets or not. Specimens where the beam bars were anchored within the base column reinforcement cage are referred to as confined specimens, whereas specimens where the beam bars were anchored outside the column reinforcement cage are referred to as unconfined specimens. For each bar size and confinement mode of the beam bars, two companion specimens were tested, identical except for whether the beam-column joint was externally wrapped with CFRP sheets or not. The test specimens are identified in Table 1. The specimens are categorized in three groups each with a different bar size. A four-part notation system was used to identify the variables in each specimen. The first part indicates the anchorage confinement mode of the beam bars in the column reinforcement cage: U for unconfined mode (beam bars outside the column reinforcement cage) and C for confined mode (beam bars within the column reinforcement cage). The second part indicates the size of the beam bars: 16, 25, or 32 mm (No. 5, No. 8, or No. 10), the
of the mode of failure of hooked bars anchored in the HSC joints. To date, there has been no research work in this area. Previous research performed at the AUB indicated a positive contribution of external confinement of FRP sheets to the bond strength of tension lap splices in NSC and HSC beam structures. It was significant to investigate if such an improvement would extend to the bond performance of hooked bar anchorages and the ductility of the failure mode of HSC beam-column connections. Such improvement would encourage the use of CFRP technology in strengthening and retrofitting distressed HSC beam-column joints, especially in earthquake-damaged and blast-damaged reinforced concrete structures.
EXPERIMENTAL PROGRAM Twelve full-scale beam-column specimens were constructed and tested using the strong floor-reaction wall testing facility in the Materials Testing Laboratory at the AUB. The specimen simulated the rigid connection of a vertical cantilever beam to a base column. The variables were bar size: 16, 25, or 32 mm (No. 5, No. 8, or No. 10), anchorage mode of the beam bars in the beam-column joint, and whether the beam-column joints were externally confined with CFRP sheets or not. Specimens where the beam bars were anchored within the base column reinforcement cage are referred to as confined specimens, whereas specimens where the beam bars were anchored outside the column reinforcement cage are referred to as unconfined specimens. For each bar size and confinement mode of the beam bars, two companion specimens were tested, identical except for whether the beam-column joint was externally wrapped with CFRP sheets or not. The test specimens are identified in Table 1. The specimens are categorized in three groups each with a different bar size. A four-part notation system was used to identify the variables in each specimen. The first part indicates the anchorage confinement mode of the beam bars in the column reinforcement cage: U for unconfined mode (beam bars outside the column reinforcement cage) and C for confined mode (beam bars within the column reinforcement cage). The second part indicates the size of the beam bars: 16, 25, or 32 mm (No. 5, No. 8, or No. 10), the
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