Dynamic Properties of SFRC Made on the Basis of Waste Sand

The article presents the results of non-destructive testing of steel fiber reinforced concrete (SFRC) based on waste sand. Fiber concrete beams with different steel fiber content were subjected to two types of free vibrations: torsional and flexural vibrations. Based on the tests and Fourier analysis, the frequencies of these vibrations were determined. They were used to determine the dynamic modulus of elasticity (Young’s modulus), the dynamic shear modulus (modulus of rigidity) and the dynamic Poisson’s ratio. In the next stage, the influence of steel fibers on these parameters was determined. The tests have shown that the addition of steel fibers increases the value of dynamic modulus of elasticity and the dynamic shear modulus up to a certain critical fiber content, beyond which the values of these moduli decrease; moreover, steel fibers do not affect the value of the dynamic Poisson’s ratio.