In this study, the effect of steel fibres reinforced concrete (SFRC) jacketing on the flexural performance of coarse recycled aggregate reinforced concrete (CRARC) beams is studied. A total of 48 reinforced concrete beams, in two categories, were manufactured and tested. In the first category, 16 reinforced concrete (RC) beams were tested, then strengthened with a jacket and tested again. In another category, 16 specimens were strengthened with a jacket and then tested. All specimens were tested using a four-point flexural setup. Coarse recycled aggregate (CRA) was used at two mass replacement ratios, 0% and 100%, in both RC beams and concrete jackets (CJs). Steel fibres (SF) was also added at 0% and 2% (by volume) in both beams and CJs. In these tests, the flexural capacity, maximum displacement at mid-span and the ductility of specimens were measured. Moreover, a new modified model was proposed to predict the flexural behaviour of SF jacketed CRA and coarse natural aggregate (CNA) beams. The obtained outcomes indicate that the maximum flexural strength and displacement of 100% CRARC beams increased substantially by strengthening RC with 2% SF reinforced CJs.

在这项研究中，研究了钢纤维增强混凝土（SFRC）护套对粗再生骨料增强混凝土（CRARC）梁抗弯性能的影响。总共制造并测试了两类48条钢筋混凝土梁。在第一类中，先对16条钢筋混凝土（RC）梁进行了测试，然后用护套对其进行了加固，然后再次进行了测试。在另一类中，用外套加固了16个标本，然后进行了测试。所有样品均使用四点弯曲装置进行测试。在RC梁和混凝土护套（CJ）中，粗再生料（CRA）以两种质量替换率（0％和100％）使用。在梁和CJ中，钢纤维（SF）的添加量也分别为0％和2％（按体积计）。在这些测试中，抗弯能力 测量了跨度的最大位移和样品的延展性。此外，提出了一种新的改进模型来预测SF护套CRA和粗天然骨料（CNA）梁的弯曲行为。获得的结果表明，通过用2％SF增强的CJ加固RC，可以大大提高100％CRARC梁的最大抗弯强度和位移。