|
Title |
Plastic Rotation Capacity of Lightweight Aggregate Concrete Beams considering Unit Weight of Concrete
|
|
Authors |
양근혁(Keun-Hyeok Yang) ; 문주현(Ju-Hyun Mun) ; 임채림(Chae-Rim Im) |
|
DOI |
https://doi.org/10.4334/JKCI.2021.33.1.031 |
|
Keywords |
보; 곡률 연성비; 변위 연성비; 경량골재 콘크리트 beams; curvature ductility ratio; displacement ductility ratio; lightweight aggregate concrete |
|
Abstract |
This study proposes simple models of curvature () and displacement () ductility ratio to reliably assess the plastic rotation capacity of reinforced concrete (RC) beams with different unit weights of concrete (). The plastic rotation capacity of RC beams is examined using the concept of and that were derived from the strain compatibility and force equilibrium at the critical section and curvature distributions idealized along the beam length. The analytical models indicate that and of RC beams decrease by approximately 47 % and 28 %, respectively, with decreases of 2,300 kg/m3 to 1,400 kg/m3. This implies that lower plastic rotation capacity is expected for lightweight aggregate concrete (LWAC) beams than for normal-weight concrete (NWC) beams at the same longitudinal reinforcement index (). In comparisons with 120 data sets compiled from the existing beam tests, the previous models proposed by Pam et al. and Arslan and Cihanli tends to overestimate of beams. This overestimation is more notable for concrete beams with lower . Meanwhile, the proposed model accurately assesses of RC beams, regardless of the variations of and , revealing that the mean and standard deviation of ratios between experiments and predictions are 0.98 and 0.20, respectively.
|