Michałowska-Maziejuk Dorota, Goszczyńska Barbara
Faculty of Civil Engineering and Architecture, Department of Strength Materials and Building Structures, Kielce University of Technology, al. Tysiąclecia Państwa Polskiego 7, 25-314 Kielce, Poland.
Materials (Basel). 2023 Jul 6;16(13):4847. doi: 10.3390/ma16134847.
The article analyses the results obtained from tests of preloaded reinforced concrete beams strengthened with carbon fibre strips bonded into the concrete reinforcement cover (NSMR method). Adhesive (thixotropic epoxy resin) bonding takes 7 days at 23 °C. The strengthening process was accelerated by heating the strip using a prototype heating device. Tests on the reinforced concrete members confirmed that accelerating the strengthening process is feasible and allowed the selection of the optimal heating temperature to provide the greatest strengthening level. The study primarily aimed to analyse the effectiveness of strengthening applied to the bottom of reinforced concrete beams under sustained loading throughout the adhesive curing process, simulating real conditions on site. Significantly higher strengthening efficiency was achieved with the use of strip heating, which accelerated adhesive cure time and reduced the strengthening execution time from 7 days to 1.5 h. The analysis included the evaluation of the effect of the steel and composite reinforcement ratios on strengthening effectiveness.
本文分析了采用粘贴碳纤维板加固混凝土保护层中的钢筋(NSMR方法)对预加载钢筋混凝土梁进行测试所获得的结果。在23°C下,胶粘剂(触变环氧树脂)粘结需要7天时间。使用原型加热装置对碳纤维板进行加热,加速了加固过程。对钢筋混凝土构件的测试证实,加速加固过程是可行的,并且可以选择最佳加热温度以提供最大的加固水平。该研究的主要目的是分析在胶粘剂固化过程中持续加载情况下,对钢筋混凝土梁底部进行加固的有效性,模拟现场实际情况。使用碳纤维板加热显著提高了加固效率,加速了胶粘剂固化时间,并将加固执行时间从7天缩短至1.5小时。分析包括评估钢材和复合加固比例对加固效果的影响。