Experimental Investigation of High-performance Fiber-reinforced Cementitious Composite and its Effect on RC Beams by Numerical Method

Abstract

In the present study, experimental investigations were initially conducted on high-performance fiber-reinforced cementitious composite (HPFRCC). A total of 9 samples were examined and subjected to a 4-point bending test. The sample lengths were standardized at 500 and 1700 mm. The variables under scrutiny included the impact of Micro Steel, Macro Steel, and polyvinyl alcohol fibers. Furthermore, the models were scrutinized under two conditions: with and without glass fiber reinforced polymer (GFRP) bars. The number of samples was 9. In the second part of the article, subsequent to verifying the experimental samples from the current study alongside a concrete beam, numerical analyses were carried out to assess the influence of HPFRCC on the behavior of RC beams. Similarly, the impact of GFRP diameter, as well as the height of HPFRCCs, on the seismic performance of RC beams, was investigated by conducting 36 numerical analyses. The analyses were carried out using nonlinear static methods, with monotonic loading. The model outputs encompass elastic stiffness, ultimate strength, relative stiffness, and energy dissipation. The experimental results showed that the use of macro steel fibers in models without GFRP rebars has better results on the flexural behavior of HPFRCC. Moreover, by reinforcing RC beams with HPFRCC, a 70% increase in energy dissipation was observed. The elastic stiffness and ultimate strength of the strengthened beam are directly proportional to the ratio of the HPFRCC's elastic flexural stiffness to that of the original beam. These results increase proportionally as this ratio rises.