Regulatory support for the use of composite rod reinforcement in concrete structures

Abstract

Currently, regulatory documents for the design of reinforced concrete structures with composite rod reinforcement do not contain unambiguous provisions for the purpose of the design resistances of the reinforcement, there are no instructions for the design of structures to ensure fire resistance. The article presents an analysis of technical documentation and experimental studies to determine the mechanical characteristics of rod composite reinforcement. As a result of the research conducted by the authors, it was found that the tensile strength of rebar decreases in some cases by 35% when the diameter of rebar rods increases from 5 mm to 10 mm. When analyzing technical documentation and test results, the coupling of composite reinforcement rods with screw winding with concrete up to 14.0 MPa is provided. It is proposed to take a value of 50 °C below the glass transition temperature of the matrix polymer as the maximum permissible temperature for heating rebar rods in a concrete structure. The directions of further improvement of the regulatory framework for the design of reinforced concrete structures with composite rod reinforcement are outlined.