Experimental investigation of reinforced concrete beams using post- tension

The paper presents the results of an experimental investigation of statically determinable pre-stressed concrete beams with tension on concrete (using post-tension). The authors consider the existing practice of applying post-tension in reinforced concrete structures, the current regulatory documents of the Russian Federation containing information on the strength and deformation properties of post-tension. The paper contains information about the loading pattern, beam-fixing conditions, geometric characteristics of a reinforced concrete beam, physical characteristics of concrete and reinforcement of an experimental sample, technical characteristics of pre-stressed reinforcement. The authors present the research results using graphs of structural deflection changes under load, the distribution of relative strain along the depth of a concrete cross-section, as well as cracking and failure schemes of experimental samples. The research presented in the paper showed that the destruction of the samples occurred along a standard cross-section and was brittle. As a result of processing the results of experimental data, loads of crack formation and critical crack width were determined. The authors confirmed the effect of pre-stressing on crack resistance and the magnitude of the deflection of bent reinforced concrete elements.