INVESTIGATION OF THE BEHAVIOR OF SUPPORT ZONES OF CONTINUOUS REINFORCED CONCRETE BEAMS UNDER REPEATED AND LOW-CYCLE ALTERNATING LOADS

Abstract

Based on the authors' and other researchers' experimental studies, this article presents an analysis of the behavior of inclined sections in the support zones of single-span and continuous reinforced concrete beams under low-cycle loads and changes in the stress-strain state depending on the shear span of the external load application.

The calculation of reinforced concrete beams inclined crack is due to many interdependent factors. Beam testing attempts to identify the main criterion for the strength of the inclined section and, based on this, proposes a method for calculating inclined sections.

The accuracy of calculating the strength of inclined sections of reinforced concrete beams on the action of the transverse force and bending moment according to the methods, according to methods based on the theory of concrete strength fully depends on the reliability of the assumptions made and functional expression of tangent stresses and normal stresses taking into account factors, considering the factors that characterize the behavior of the reinforced concrete element in the shear span.

If we compare these calculation methods with the method based on the equilibrium of limiting forces, the latter is the least labor-intensive for designers.

Current regulatory documents [1] propose a method for calculating inclined sections using a strut-and-tie model (truss analogy of the new European standards [2]), which also has a number of difficulties in actual calculations of the transverse sections of beams. In this case, bent bars in beams can be used as transverse reinforcement in combination with vertical transverse bars.