Size effect in shear failure of RC beams reinforced with CFRP sheets: Influences of CFRP adhesion angle and shear-span ratio

• Published in: Engineering structures 2025-03, Vol.326, p.119543, Article 119543
• Main Authors: Jin, Liu, Qin, Peng, Zhang, Jiangxing, Li, Dong, Jiang, Xuan-ang, Du, Xiuli
• Format: Article
• Language: English
• Subjects: Adhesion angle; CFRP reinforced RC beams; Shear performance; Shear-span ratio; Size effect
• ISSN: 0141-0296
• DOI: 10.1016/j.engstruct.2024.119543

The study investigates the influence of the shear performance and size effects of reinforced webless RC beams under the coupling of the shear-span ratio (λ = 1.0, 1.5, and 2.0) and the attachment angle (θ = 0°, 30°, 45°, 60°, and 90°) of the CFRP sheets, based on four-point bending loading test. The results show that: the damage modes exhibited by the specimens remain consistent when the shear-span ratios are equivalent; when the CFRP sheets are nearly perpendicular to the main diagonal crack, they have a stronger effect on the RC beams, but they also weaken the size effect of the reinforced beams; the CFRP sheets' strain quickly increases after the diagonal cracks show up; CFRP sheet enhances the shear capacity of RC beams without web by up to 83 percent. Finally, we propose a size effect formula for the shear strength of CFRP sheet-reinforced RC beams without web reinforcement, considering the coupled effects of the shear-span ratio and CFRP sheets' adhesion angle, based on the experimental and simulation results. •The effects of shear-span ratio on shear performance of CFRP-reinforced RC beams are investigated experimentally.•The outcomes of additional CFRP sheet adhesion angle situations are expanded and analyzed in numerical simulation.•A shear size effect law of CFRP-reinforced RC beam considering the effect of adhesion angle and shear-span ratio is proposed.