Vestnik of Samara University. Natural Science SeriesVestnik of Samara University. Natural Science Series2541-75252712-8954Samara National Research University1015410.18287/2541-7525-2021-27-2-62-69Research ArticleINFLUENCE OF CURVATURE OF THE CRACK TIP RADIUS ON STRESSESGerberY. A.<p>senior lecturer</p>yu.gerber@sibstrin.ruhttps://orcid.org/0000-0001-8846-9230NagelA. E.<p>student</p>a.nagel@edu.sibstrin.ruhttps://orcid.org/0000-0002-2656-0140TabanyukhovaM. V.<p>Сandidate of Technical Sciences, associate professor</p>tabanyukhova@sibstrin.ruhttps://orcid.org/0000-0003-3279-8160Novosibirsk State University of Architecture and Civil Engineering (Sibstrin)3105202127262693003202230032022Copyright © 2021, Gerber Y.A., Nagel A.E., Tabanyukhova M.V.2021<p>In experimental mechanics, when conducting research on models, the question often arises of whether it is legitimate to replace a crack with a cut, whether the radius of curvature of the cut will have a large effect on the magnitude of stresses near its apex. In order to understand these questions and give answers to them, a number of experiments were carried out on samples made of piezo-optical material (Plexiglass of E2 grade). In the models, the crack was simulated using a cut, then a hole was made at the top of the cut with a drill. The models were investigated in pure bending by the photoelasticity method. Stress fields were obtained in two batches of samples at different loads. The intensity of stresses near cracks-cuts at different radius of curvature of their tops was determined by using the experimental data. An assessment of the influence of the crack-cut tip radius curvature on the magnitude of stresses near it has been carried out.</p>экспериментальная механика, модели, трещины, метод фотоупругости,
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