Diagrams of Deformation of Cement Composites Reinforced with Steel Wire Fiber

Abstract

Modern construction practice acquires such a tendency, at which it is required to use materials with increased physical, mechanical and operational characteristics, and at the same time, do not require significant material, labor and energy costs for their production. One of the most promising building materials that meet the requirements is fiber-reinforced concrete. However, the increase in the volume of its use is limited by the insufficient degree of study of its properties and characteristics. This problem is aggravated by the constantly expanding range of reinforcing fibers, which can give composites produced on their basis, completely different properties and characteristics.
 One of the most important characteristics of fiber-reinforced concrete is crack resistance. The most informative method of research of this characteristic is the construction and analysis of deformation and fracture diagrams of samples obtained during bending tensile strength tests. At the initial stage of the described study, several series of fiber-reinforced concrete samples were tested. During the tests, a standard method for assessing the fracture toughness of heavy and fine-grained concretes, governed by the requirements of GOST 29167, was used. A device specially designed for testing fiber-reinforced concrete was used.
 As a result of the tests, a general view of the deformation diagrams of fiber-reinforced concrete samples was established, strength and energy characteristics of crack resistance, as well as the modulus of elasticity were found, and the labor intensity of the tests was high.
 In this paper we describe a possible way of obtaining fracture patterns for fiber-reinforced concrete by calculation. The resulting diagrams of deformation of fiber-reinforced concrete samples are built on several key points, the determination of which coordinates is made by calculation.
 The paper compares the experimental and calculated fracture toughness characteristics of fiber-reinforced concrete manufactured using steel wire fiber. Comparison of the data presented indicates a satisfactory agreement between the calculated and experimental data, which proves the validity of the proposed method for obtaining fiber-reinforced concrete deformation diagrams.