Results of experimental research of steel-concrete composite beam under cyclic freezing-thawing

Abstract

One of the ways to improve the efficiency and quality of reinforced concrete structures is the development and implementation of new building structures, the use of which ensures a decrease in material consumption and cost. These effective structures include steel-concrete structures. An important problem when using steel-concrete structures is to ensure the joint work of steel and concrete, which is determined by the adhesion of materials. Reinforced concrete structures must meet the requirements for safety, serviceability and durability. The question of the operation of steel-concrete structures with external reinforcement in the form of a box section remains poorly understood. At the same time, the question of the influence of cyclic freezing and thawing on the adhesion strength between the metal shell and concrete remains open. In order to identify the features of the work of bent steel-concrete elements with external reinforcement at alternating temperatures, experimental studies were carried out, the results of which on strength and deformability are presented in this article. Investigations were carried out in two directions: first, the influence of the CFT on the change in the adhesion strength between the metal shell and concrete under compression; the second influence of CFT on the joint work of concrete and metal in bent steel-concrete elements.