Flexural behavior of SFRC-NC composite beams: An experimental and numerical analytical study

In this study, the flexural behavior of SFRC-NC composite beams cast with normal concrete (NC) and steel fiberreinforced concrete (SFRC) were investigated. Nine SFRC-NC composite beams were designed and tested through four-point bending (FPB) experiments, including one reference beam with normal concrete (NC) and eight beams with different SFRC layer thicknesses. The effect of the designed parameters, including the SFRC layer thickness, diameter of steel rebar, and fiber content, on the flexural behavior of the beams was investigated experimentally. Compared to beams cast with normal concrete, the experimental results showed that the application of SFRC can effectively improve the bearing capacity of RC beams. These improvements include the crack-initial load, yield load, ultimate load, and ductility. Based on the experimental results, an FE macro-model was developed, and a series of numerical analyses were conducted to investigate the flexural behavior of SFRC-NC composite beams.