According to regulatory requirements, the Khakassia Republic is characterized by high seismicity, and therefore reliability and safety requirements are imposed on buildings and structures in accordance with SP 14.13330.2014 “Construction in seismic regions”. It is necessary to significantly reduce or eliminate the likelihood of an emergency, to ensure the necessary margin of safety and durability of buildings. It is possible to achieve such a multifaceted effect, including through the introduction of construction technologies using fiber-reinforced concrete. The experience of Russian and foreign researchers shows that the use of fiber-reinforced concrete in various structures makes it possible to achieve higher tensile strength, no shrinkage and resistance to cracking, as well as high impact strength and plasticity. In this regard, the study of the possibility of using fiber-reinforced concrete in the conditions of the Khakassia Republic is relevant. The purpose of this work is to study structures using fiber-reinforced concrete based on basalt fiber, which has increased strength, as well as to analyze the stress-strain state of models of various structures. The article presents the results of determining the optimal percentage of concrete reinforcement with basalt fiber based on the study of the kinetics of changes in strength in compression and bending. The paper presents the dependences of changes in strength and shrinkage deformations on the percentage of reinforcement. It is shown that concretes with 2% fiber content are characterized by the best performance. It is noted that an increase in the percentage of fiber reinforcement does not always lead to an increase in strength due to the uneven distribution of fiber throughout the volume. The authors investigated the stress-strain state of bending elements (slabs, beams) based on fiber-reinforced concrete. It is shown that when using basalt fiber, there is a decrease in the percentage of reinforcement with working reinforcement of reinforced concrete elements to 26–57 %.

Keywords: Fiber concrete, basalt fiber, percentage of reinforcement, bending element, shrinkage, deformation, stress-strain state, compressive strength, flexural strength, steel economy