Exploratory study of adopting longitudinal column reinforcement details as a design-controllable tool to seismic behavior of exterior RC beam-column joints. (1st November 2018)

• Record Type: Journal Article
• Authors: Fahmy, Mohamed F.M.; Farghal, Omar A.; Sharobeem, Girgis F.G.
• Is Part Of: Engineering structures. Volume 174(2018)
• Page Start: 95
• Page End: 110
• Publication Date: 2018-11-01
• Subjects: Bond-based control -- Exterior joint -- Joint distortion -- Lap-splice -- BFRP rebars -- Seismic; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2018.07.050
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Column reinforcement details control the lateral response of beam-column joints. Well-detailed lap-splice ensures the development of a sole resisting mechanism. Well-detailed lap-splice + FRP rebars lead to a reduction in the joint deformability. Code provisions for splicing longitudinal column reinforcement should be revised. Abstract: This study presents the test results of seven exterior beam-column joints with different longitudinal reinforcement details for the columns. The test program included a beam-column joint designed to serve as a control specimen, in which column reinforcement was continuous ribbed steel bars. The other six specimens were divided into two groups, three specimens for each group. In the first group, the longitudinal column reinforcement was detailed with well-confined lap-splice longitudinal bars: two specimens were reinforced with lap-splice deformed steel bars and the later was with lap-splice plain steel bars. The same reinforcement details were used for the second group but additional longitudinal basalt fiber reinforced polymer (BFRP) rebars were placed at the joint and extended to the upper and lower columns. The test results showed that splicing the longitudinal column reinforcement successfully reduced the contribution of the joint to the deformability of the beam-column joint. Furthermore, adding BFRP rebars to the beam-column joint could be applied as damage controllable bars reducing both the damage level at the serviceability state and the shear deformability of the joint up to failure. A sole strut resistant mechanism was realized by the joints of all test specimens detailed with lap-spliced longitudinal column reinforcement. Ultimately, the test results point to a probability to the renunciation of the ACI 318-11 requirements for splicing longitudinal column reinforcement at column mid-height.