Evaluation of the effect of fibers on the strength characteristics of concrete

The article presents the results of research of different fibers on the effect of strength characteristics of fine-grained concrete. The basic characteristics of the types of fibers used for the manufacture of fiber concrete are given. The results of laboratory research of polypropylene and basalt fibers for dispersion reinforcement of concrete are given. To estimate the strength changes the samples were made and tested in compression at the age of 3, 14 and 28 days of normal-moist hardening. The results of determining the compressive strength of fine-grained fiber concrete without adding fiber (control composition) and with the addition of polypropylene fiber 0.1, 0.5, 1.5, 2.5% of the mass of cement and basalt fiber 0.05, 0.1, 0.2, 0.5% of the mass of cement are given. It is shown that the most optimal limits of the introduction of polypropylene fiber in the mixture can be considered 0.5% of the weight of cement, which leads to an increase in compressive strength up to 9.09%, compared with the control composition. The introduction of basalt fiber in the mixture of fine-grained concrete in an amount of 0.1% of the weight of cement can increase the compressive strength by 11.4%.