Quasi-brittle fracture of a structurally inhomogeneous material with a circular hole under compression
https://doi.org/10.31242/2618-9712-2020-25-2-11
Abstract
The paper presents results of experimental and theoretical studies on fracture of gypsum plates containing a circular hole and subjected to non-uniformly distributed compression. The tested specimens were made of high-strength gypsum, and from gypsum plaster. The specimens of high-strength gypsum were broken in the brittle manner, while the specimens of gypsum plaster demonstrated quasi-brittle fracture. To calculate the critical load, amodified nonlocal fracture criterion is proposed, which is the development of the average stress criterion, and which contains a complex parameter that characterizes the size of the fracture process zone and accounts not only for the material structure, but also for the plastic properties of the material, geometry of the specimen, and its loading conditions. The calculation results are in good agreement with the experimental data. In addition, the application of the modified nonlocal criterion makes it possible to explain the change in the character of fracture from brittle to ductile with an increase in the size of the hole, observed in the experiment. The results obtained are of great practical significance for assessment on the strength of materials and structures with stress concentration.
Keywords
Supporting agencies: The research was financially supported by the Russian Foundation for Basic Research under grant number 18-05-00323.
About the Author
S. V. Suknev
Chersky Institute of Mining of the North SB RAS
Russian Federation
Russian Federation
SUKNEV Sergey Viktorovich, doctor of technical sciences, head of laboratory
43 Lenina pr., Yakutsk, 677980
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Review
For citations:
Suknev S.V. Quasi-brittle fracture of a structurally inhomogeneous material with a circular hole under compression. Arctic and Subarctic Natural Resources. 2020;25(2):137-146. (In Russ.) https://doi.org/10.31242/2618-9712-2020-25-2-11
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