Effect of whisker toughening on the dynamic properties of hybrid fiber concrete

In the present study, the test analyzed the effect of calcium carbonate whisker powder on the properties of hybrid fiber concrete incorporated with basalt and mesh polypropylene fibers. Mixed and single fiber concrete were set up for comparative study. The strain rate, pore change, and morphology of concrete were tested by split Hopkinson pressure bar (SHPB), NMR, and SEM, respectively, and the action mechanism of the calcium carbonate whisker hybrid fiber concrete was analyzed. The study showed that the addition of whiskers and hybrid fibers to concrete can effectively improve the compressive and flexural strengths compared with ordinary and single fiber concrete. The porosity optimization of the whisker toughening hybrid fiber concrete was remarkably optimized, and the strength and toughness are particularly improved. The strain rate was enhanced by improving the impact resistance under the impact load. Results also revealed that whiskers and two kinds of fibers have different sizes and physical and mechanical properties, which enable their functioning in different dimensions and damage stages to improve the strength and toughness of the concrete.