PSI - Issue 2_B

Oleg B. Naimark / Procedia Structural Integrity 2 (2016) 342–349 Author name / Structural Integrity Procedia 00 (2016) 000–000

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roads corresponding to the “spall dynamic branch” regime; scaling analysis of fragmentation statistics based on the “in-situ” recorded fracture luminescence signals in dynamically loaded glass and ceramic rods and analysis of fragment mass statistics in recovered samples. It was shown that crack branching dynamics, failure wave, multicenter spall failure, fragmentation statistics are related to the specific class of the universality for multiscale damage localization phenomena – the excitation of multiscale blow-up collective modes of defects, which can be considered as the independent collective variables. Morphological image of these modes on the fracture surface is the mirror zones. The failure wave and “dynamic branch” phenomena correspond to the case of “resonance excitation” of blow-up regime of damage localization with pronounced features of “delayed failure” Qualitative changes in the fragmentation statistics (both temporal and fragment size distribution) were found: transition from exponential to power law statistics with increasing of load intensity. This result supported theoretical prediction concerning self-criticality scenario of fragmentation caused by multiscale blow-up damage localization kinetics Acknowledgements Research was supported by the Russian Science Foundation (grant no. 14-19-01173). References Belyaev, V., Naimark , O., 1990. Localized blow-up structures in failure of solid under intensive loading, Sov . Phys. Dokl. 312,289-293. Bellendir, E., Belyaev, V., Naimark,O., 1989. Kinetics of multicenter failure in spall conditions. Sov. Tech.Phys. Lett. 15, 90-93. Davydova, M., Naimark, O., Leontiev, V., Uvarov, S., 2010a. Scaling properties of crack branching and brittle fragmentation, European Physical Journal Web of Conferences, 10 (2010)00037p.1-00037p.4, URL http://www.epj.org DOI: 10.1051/epjconf/20101000037. Davydova, m., Uvarov, S., Naimark, O., 2014b. Scale invariance in dynamic fragmentation Physical Mesomechanics 17,81-88. Grady, D., 2010. Length scales and size distributions in dynamic fragmentation. Int.J.Fracture 163,85-99. Naimark, O., 2004a. Defect Induced Transitions as Mechanisms of Plasticity and Failure in Multifield Continua, In: G.Capriz and P.Mariano (Eds.), Advances in Multifield Theories of Continua with Substructure, Birkhauser Inc., Boston, 75-114. Naimark, O., Uvarov,S., 2004b. Nonlinear crack dynamics and scaling aspects of fracture (experimental and theoretical study. Int. J. Fracture 128,285-292. Naimark, O., Uvarov, S., Radford, D., Proud, W., Field, J., Church, P., Cullis, I., Andrews, T., 2003c. The failure front in silica glasses. In: A.Delpuech (Ed.), Behavior of Dense Media under High Dynamic Pressures, Cambridge, .2, 65-74. Plekhov, O., Eremeev, D., Naimark, O., 2000. Failure wave as resonance excitation of collective burst modes of defects in shocked brittle materials. J. Physique IV Colloq C, 10,811-816. Rasorenov, S., Kanel, G., Fortov, V., Abasenov, M., 19 91. The fracture of glass under high-pressure impulsive loading. High Press. Res. 6,225-232.