Pang Miao, Shi Sensen, Hu Han, Lou Tiejiong
Department of Civil Engineering, Zhejiang University, Hangzhou 310058, China.
Hubei Key Laboratory of Roadway Bridge & Structure Engineering, Wuhan University of Technology, Wuhan 430070, China.
Materials (Basel). 2021 Nov 9;14(22):6746. doi: 10.3390/ma14226746.
This paper investigates the feasibility of replacing steel bars with carbon-fiber-reinforced polymer (CFRP) bars in continuous reinforced concrete (RC) beams. A numerical model is introduced. Model predictions are compared with the experimental results that are available in the literature. A comprehensive numerical investigation is then performed on two-span CFRP/steel RC beams with = 0.61-3.03% and / = 1.5, where and are tensile bar ratios (ratios of tensile bar area to effective cross-sectional area of beams) over positive and negative moment regions, respectively. The study shows that replacing steel bars with CFRP bars greatly improves the crack mode at a low bar ratio. The ultimate load of CFRP RC beams is 89% higher at = 0.61% but 7.2% lower at = 3.03% than that of steel RC beams. In addition, CFRP RC beams exhibit around 13% greater ultimate deflection compared to steel RC beams. The difference of moment redistribution between CFRP and steel RC beams diminishes as increases. ACI 318-19 appears to be conservative, and it leads to more accurate predictions of moment redistribution in CFRP RC beams than that in steel RC beams.
本文研究了在连续钢筋混凝土（RC）梁中用碳纤维增强聚合物（CFRP）筋替代钢筋的可行性。介绍了一个数值模型。将模型预测结果与文献中现有的试验结果进行了比较。然后对跨高比为1.5、拉筋配筋率（拉筋面积与梁有效截面积之比）在正、负弯矩区分别为0.61% - 3.03%的两跨CFRP/钢RC梁进行了全面的数值研究。研究表明，在低配筋率情况下，用CFRP筋替代钢筋可显著改善裂缝形态。当拉筋配筋率为0.61%时，CFRP RC梁的极限荷载比钢RC梁高89%，但当拉筋配筋率为3.03%时，比钢RC梁低7.2%。此外，与钢RC梁相比，CFRP RC梁的极限挠度大约大13%。随着拉筋配筋率的增加，CFRP和钢RC梁之间的弯矩重分布差异减小。ACI 318 - 19规范似乎较为保守，与钢RC梁相比，它能更准确地预测CFRP RC梁中的弯矩重分布。
