Rational Design of Composite Strengthening of Reinforced Concrete Elements for Experimental Research

In recent years, due to the increase in design loads in operated buildings, there is a need to strengthen their load-bearing structures. The use of high-modulus composite materials contributed to the further development of reinforcement methods. The analysis of the works related to the composite reinforcement of reinforced concrete bendable structures showed the need for experiments with a variation in the ratio of the length of the composite reinforcement to the calculated length of the element. This paper presents a preliminary calculation and selection of options for strengthening reinforced concrete bendable elements, including their inclined sections, for further field experimental studies using normative methods. Reinforced concrete beams made of concrete of strength class B15 were selected as the studied samples. The reinforcement is made in the form of a flat frame using rods of classes B500 and A400. Composite reinforcement is made using SikaWrap carbon tapes. The location of the breakage of the composite reinforcement in the stretched zone of the element is determined when plotting the load-bearing capacity of the non-reinforced element and the bending moments from the maximum possible load of the reinforced elements. An increase in the bearing capacity may lead to a change in the pattern of destruction of the sample, which requires additional calculation and design of composite reinforcement of inclined sections of the element.