Lee Eun-Taik, An Jae-Hyoung, Song Jun-Hyeok, Hong Yu-Sik, Eun Hee-Chang
Department of Architectural Engineering, Chung-Ang University, Seoul 06974, Korea.
Department of Architectural Engineering, Kangwon National University, Chuncheon 24341, Korea.
Polymers (Basel). 2022 Aug 31;14(17):3596. doi: 10.3390/polym14173596.
Structures constructed before seismic design standards in Korea were enacted are being seismically and structurally strengthened for structural performance. The jacket method has been used to enhance the shear load-carrying capacity and ductility of reinforced concrete columns. This study investigated the effect of glass fiber-reinforced polyurea (GFRPU) on the enhancement of shear strength and ductility. It was shown that the GFRPU spraying technique played an important role in enhancing the column because of the material characteristics of the GFRPU, that is, high-tensile strength and elongation. The reinforcement effect of GFRPU on the shear-span ratio and axial-force ratio of six reinforced concrete (RC) column specimens was evaluated. The experimental results demonstrated that the lateral-reinforcement effect and energy-dissipation capacity were improved. The H-series and S-series specimens reinforced by the GFRPU with an axial-load ratio of 0.1 exhibited higher shear strength, of about 30% and 18%, than the specimens without reinforcement. The shear-load-carrying capacity of the S-series specimen with the axial-load-force ratio of 0.2 increased by 4%. The design method representing the lateral-resistance ability of the GFRPU was represented by an empirical formula reflecting the experimental results.
在韩国抗震设计标准颁布之前建造的结构，正通过抗震和结构加固来提高结构性能。外套法已被用于增强钢筋混凝土柱的抗剪承载能力和延性。本研究调查了玻璃纤维增强聚脲（GFRPU）对提高抗剪强度和延性的影响。结果表明，由于GFRPU的材料特性，即高抗拉强度和伸长率，GFRPU喷涂技术在增强柱体方面发挥了重要作用。评估了GFRPU对六个钢筋混凝土（RC）柱试件的剪跨比和轴力比的增强效果。试验结果表明，其横向加固效果和能量耗散能力得到了改善。轴向荷载比为0.1的GFRPU加固的H系列和S系列试件，其抗剪强度比未加固的试件分别高出约30%和18%。轴向荷载力比为0.2的S系列试件的抗剪承载能力提高了4%。反映GFRPU抗侧力能力的设计方法由一个反映试验结果的经验公式表示。
