|
Title |
Evaluation of Anchorage Performance of SD700 Headed Bars Anchored at Beam Ends
|
|
Authors |
박상아(Sang-Ah Park) ; 정민기(Min-Gi Jung) ; 김승훈(Seung-Hun Kim) |
|
DOI |
https://doi.org/10.11112/jksmi.2025.29.1.43 |
|
Keywords |
확대머리 철근; 고강도 철근; 정착; 강섬유 보강 콘크리트; 스트럿-타이 모델 Headed bar; High-strength reinforcement; Anchorage; Steel fiber reinforced concrete; Strut-tie model |
|
Abstract |
This study conducted shear tests to evaluate the mechanical anchorage performance of SD700 high-strength reinforcement at the ends of reinforced concrete (RC) and steel fiber-reinforced concrete (SFRC) beams. A total of eight specimens were fabricated, with variables including the anchorage method of the main reinforcement, development length, presence of shear reinforcement, and steel fiber content. The experimental results revealed that initial flexural cracks formed beneath the loading points in all specimens. Subsequently, diagonal cracks developed, and the final failure modes were identified as either anchorage failure or shear-compression failure. Compared to the S-series specimens with straight anchorage, the H-series specimens anchored with headed bars exhibited significantly higher anchorage stresses, ranging from 7.6% to 44.6%, indicating improved anchorage performance due to the headed bars. The theoretical nominal shear strength of specimens was evaluated using the strut-and-tie model. The failure mode of all specimens by the strut-and-tie model was the anchorage failure of the tensile reinforcements in the node region at beam ends. The experimental maximum shear strength to theoretical nominal shear strength ratio ranged from 1.9 to 4.37, suggesting that the development lengths specified in the current standards may be overestimated.
|