Comparative analysis of calculation of the stress intensity factor based on the results of equilibrium and non-equilibrium tests
https://doi.org/10.31659/0005-9889-2022-612-613-4-5-46-51
Abstract
The practical use of methods for determining the stress intensity factor (SIF) at normal separation was studied: eccentric compression of notched cubes and four-point bending of a notched beam. During non-equilibrium tests, the SIF value was calculated from the value of the breaking load. During quilibrium tests, the SIF value was determined from the complete equilibrium deformation diagram, taking into account the energy indicators of destruction. The test used nanofiberconcrete, in which carbon nanotubes are used as crack propagation inhibitors at the level of the cementing agent, and various macro-sized fibers are used at the level of fine-grained concrete. As a result of the tests, it was found that the methods for determining the SIF from cubes with a notch and from deformation diagrams showed a good degree of convergence. Fiber reinforcement has an effect on the fracture toughness of a nano-cement composite, and a high-modulus fiber has a greater effect on the fracture toughness index than a low-modulus one. The stress intensity factor is a good indicator for comparing different types of fiber reinforcement in terms of their effect on fracture toughness.
About the Authors
E. A. SadovskayaS. N. Leonovich
Belarusian National Technical University; Qingdao University of Technology
Belarus
Belarus
Doctor of Sciences (Engineering), Professor, Foreign Academician of RAACS
e-mail: snleonovich@yandex.ru, CEF@bntu.by
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Review
For citations:
Sadovskaya E.A., Leonovich S.N. Comparative analysis of calculation of the stress intensity factor based on the results of equilibrium and non-equilibrium tests. Concrete and Reinforced Concrete. 2022;612-613(4-5):46-51. (In Russ.) https://doi.org/10.31659/0005-9889-2022-612-613-4-5-46-51
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