PSI - Issue 32

Anatoly M. Bragov et al. / Procedia Structural Integrity 32 (2021) 340–344 Author name / Structural Integrity Procedia 00 (2019) 000–000

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each test to construct empirical dependencies. These dependences are shown in Figure 4. It is seen that an increase of the values of the energy characteristics with an increase of the strain rate can be described by a linear function of the form E = A έ+ B , where the coefficients A and B are given in Table 1. In addition, an increase of energy absorption E occurs due to a more intense growth of the post-fracture energy E 2 compared to an increase of the pre-fracture energy E 1 in the process of deformation and subsequent fracture. Similar patterns were revealed by Bragov et al. (2015) during dynamic tests of fine-grained concrete. 4. Conclusions The deformation diagrams of sand-lime brick obtained under uniaxial dynamic compression were used to estimate its deformation energy capacity. The plotted specific energy absorption plots had a non-linear form. It showed that necessary to do a lot of work to achieve a certain strain value with an increase of the strain rate. The constructed dependences of the energy characteristics showed its linear growth with an increase of the strain rate. The growth of the post-fracture energy occurs more intensively than growth of the pre-fracture energy. A similar nature of the change of the considered mechanical properties was noted not only for the investigating material but also for the previously studied brittle media (fine-grained concrete).

Acknowledgements

The experimental study of brick was carried out at the expense of a grant from the President of the Russian Federation for state support of young Russian scientists No. MK-3526.2021.4 (Agreement No. 075-15-2021-256). The energy absorption analysis was carried out with the financial support of the Russian Science Foundation (grant 21-19-00283).

References

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