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The research contains the results of experiments for determination of the level of adhesion to concrete for both fiberglass and metal reinforcement, to formulate the corresponding dependences of the tangential adhesion-displacement stresses. The object of the study is the slip value of fiberglass composite reinforcement HARD+ with and without additional sand coating, as well as standard metal reinforcement of class A400. The research of the level of adhesion between reinforcement and concrete were carried out by the beam method, which involves testing of concrete beams special samples, with specified geometric parameters, for bending in the laboratory. During the tests it was determined that the slip value of fiberglass reinforcement, in the moment of beam destruction, correlates with similar values for metal reinforcement. The experimental slip value of fiberglass reinforcement with sand coating, in the moment of destruction, is less than that of fiberglass reinforcement without sand coating, due to the higher adhesion of this type of reinforcement with concrete. The results of these research can be used in the design of load-bearing concrete structures using composite reinforcement, as well as for further development and improvement of existing Ukrainian building codes. [ABSTRACT FROM AUTHOR]

The paper presents information on the effect of polymer modifiers on the variation in production conditions and the main operational properties of filled acrylic systems, cured by the mechanism of radical polymerization. By preliminary injection and dissolution in the monomeric phase of modifiers - suspension polystyrene and its copolymers (with methyl methacrylate, methyl methacrylate and acrylonitrile) acrylic compounds were obtained with acceptable indicators of technological viscosity and the ability to adjust its viability under normal conditions. The combination of manufacturability and realizable physical characteristics of modified acrylic polymers made it possible to carry out on their basis the directed development of filled adhesive compositions with improved adhesion characteristics. According to the experimental data of relaxation spectroscopy and the calculated values of linear dilatometry, it was evaluated that when a filler is injected into the acrylic system, a supramolecular structure with a characteristic surface layer is formed, which makes a significant contribution to the variation in the macrophysical characteristics of the material (an increase in the dynamic shear modulus from 1.6 to 2.4 GPa). Therefore, mobilization to preserve the resource of the adhesive contact (not less than 18 MPa) with permissible amounts of filler (from 10 to 30 mass parts in polyacrylate) and thicknesses of the adhesive layer occurs due to the total contribution of the dispersed phase to the strengthening of the polymer. The superposition of various factors, and first of all, a decrease in the density of the polymer phase in the filled system, contributes to a slight drop in the adhesion strength of acrylic glue to a metal substrate, which in general should provide an acceptable degree of reliability of adhesive building constructions. [ABSTRACT FROM AUTHOR]