|
Title |
Evaluation of Bond Strength of L-Shaped Steel with Welded Deformed Reinforcing Bars in RC and SFRC
|
|
Authors |
양성주(Sung-Ju Yang) ; 서창우(Chang-Woo Seo) ; 박해용(Hae-Yong Park) ; 김승훈(Seung-Hun Kim) |
|
DOI |
https://doi.org/10.11112/jksmi.2025.29.1.52 |
|
Keywords |
ㄱ형강; 푸쉬아웃 실험; 이형철근; 부착강도; 강섬유 L-shaped steel; Push-out test; Deformed reinforcing bars; Bond strength; Steel fiber |
|
Abstract |
This study evaluated the bond performance of small L-shaped steel members with deformed bars welded as shear reinforcement in RC (reinforced concrete) and SFRC (steel fiber-reinforced concrete). Experimental results showed that most specimens exhibited splitting failure, with cracks forming along the flange edges of the L-shaped steel members. Furthermore, as the concrete cover thickness and bond area increased, the maximum load also increased. When the cover thickness was increased by approximately 1.7∼2.3 times, the bond stress improved by 55.4∼116.7%. However, when the bond area doubled, the bond stress decreased by approximately 17.0∼19.3%. Steel fiber reinforcement had a greater impact on preventing rapid stiffness degradation after the maximum load than on the bond stress itself. The lower 5% bond stress of all test specimens was evaluated as 1.75 MPa, which is 2.65 times higher than the bond stress specified in KDS 14 31 80. Based on the push-out tests, a nominal bond strength (Rn_k) design formula was proposed for small L-shaped steel members with deformed bar shear reinforcement details, considering the lower 5% bond stress.
|