: 212-217
Lviv Polytechnic National University, Department of Architectural Environment Design
Department of Materials Strength and Structural Mechanics
Lviv Polytechnic National University, Department of building construction and bridges
Lviv Polytechnic National University, Department of building construction and bridges

The research of reinforced concrete beams, in which there is some damage or defects are scare. This is especially applies to studies in which defects arise under the influence of the load, which is due to the complexity of such studies. This article describes a method for performing damage to stretched rebar in bending reinforced concrete elements under load. There were eight samples tested: four specimens tested as controls and four – with injuries. Control samples with a stretched rebar of 16 and 20 mm in diameter are reinforced. Damaged beams with rebar 20 mm in diameter are reinforced. Damage was carried out by drilling the hole diameters 5.6 mm in the stretched armature. The remaining area of the tensile rebar with the hole corresponds to the cross-sectional area of the reinforcement Ø16. There were simulated pointing damage of stretched reinforcement. As a result, the type of beam’s destruction was changed. Exhaustion of the bearing capacity occurs abruptly, with the breakdown of the beam into two parts. The convergence of the results of the carrying capacity of the twin samples showed a deviation of the results in the range of 3–13%.

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