Experimental and numerical simulation research on the flexural performance of beams reinforced with GFRP bars and three-sides UHPC layer

This paper presents the results of the experimental investigation and numerical investigation conducted to study the flexural response of reinforced concrete beams reinforced with glass fiber reinforced polymer (GFRP) bars using three-sides ultrahigh performance concrete (UHPC) layer. The interface treatment of bubble wrap was applied in the internal surface of UHPC layer to ensure the enough interfacial bond behavior between UHPC layer and original concrete. Three tested beams, including two beams reinforced with three-sides UHPC and a reference beam, were studied through four-point bending tests and the effectiveness of flexural strengthening scheme associated with three-sides UHPC layer was evaluated. The results showed that the cracking load and ultimate load of beams reinforced with UHPC increased by 36.7%, 55.3%, and 30.0%, 42.7%, respectively, relative to the reference beam. The employment of UHPC layer could effectively control the development of surface crack width in beams. In addition, parametric studies were conducted to investigate the effects of the height of the UHPC, the thickness of the UHPC on both sides, and the longitudinal length of the three-sided UHPC layer using finiteelement (FE) analysis. The results of numerical simulation were good agreement with the experimental results, indicating that the proposed finite element model could accurately predict the flexural responses of beams.