Mazurak R. Anchoring of rod reinforcement in fiber concrete

The dissertation is dedicated to the study of the anchoring of rod reinforcement of class A500C in fiber concrete reinforced with steel fiber with bent ends of the HE1050 type of Ukrainian production and the development of proposals for the calculation of normal stresses in the loaded ends of the rods and tangential stresses between the rods and steel fiber concrete at various stages of work during their extraction, as well as proposals regarding the determination of the basic and estimated length of anchoring. The performed research work contains the results and analysis of experimental and analytical methods, as well as mathematical modeling methods, which are used to evaluate the adhesion of rod reinforcement with fiber concrete. The conducted studies included the study of the influence of concrete strength, the ratio of the anchoring length of the rod to its diameter, the coefficient of fiber reinforcement by volume and the diameter of the rods on the development of shifts and stresses in the rods and tangential stresses between the rods and fiber concrete. A full four-factor experiment plan (plan 24) was used and regression equations were obtained to determine the stresses in the rods for the initial displacement, for a displacement of 0.1 mm and for the maximum stress values, as well as the corresponding tangential stresses between the rods and fiber concrete. Based on the experimental data obtained using a full four-factor experiment, a methodology for calculating normal and tangential stresses is proposed. Based on the theoretical analysis of the conducted studies, taking into account the available normative sources and the conducted experimental studies, an analytical dependence is proposed for calculating the ultimate stresses of the connection of rods with fiber concrete and an algorithm for determining the estimated anchoring length.