PSI - Issue 28

ScienceDirect Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2020) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2020) 000–000 Available online at www.sciencedirect.com Procedia Structural Integrity 28 (2020) 2026–2031

www.elsevier.com/locate/procedia

www.elsevier.com/locate/procedia

1st Virtual European Conference on Fracture Calculation of fracture location in multiple spalling 1st Virtual European Conference on Fracture Calculation of fracture location in multiple spalling

N. V. Mikhailova a1 , Yu. V. Petrov a N. V. Mikhailova a1 , Yu. V. Petrov a a Saint Petersburg University, Universitetsk ya nab 7/9, Saint Petersburg, 199034, Russia

a Saint Petersburg University, Universitetskaya nab 7/9, Saint Petersburg, 199034, Russia

© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Abstract The paper proposes a model that allows us to determine the fracture location in case of multiple spalling. The incubation time criterion was used to predict fracture in material. Modeling was performed for spall fracture performed on concrete rods. Comparison of the calculation results with experimental data was carried out which showed the coincidence of the predicted fracture zone with spall sections in the samples. © 2020 Th Authors. Publish d by ELSEVIER B.V. This is an open access art cle under the CC BY-NC-ND license (https://creativec mmons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Keywords: spall fracture, dynamic strength, incubation time, multiple spalling. Introduction Material strength under dynamic impact is an urgent problem to this day. The high speed of the fracture process and its instability cause difficulties in the study of dynamic strength. In order to be able to control the process of dynamic fracture, as well as to use simplified formulations of problems in its modeling, special experimental techniques have been developed. Some of the most important of them are based on the phenomenon of spall fracture. This technique makes it possible to test the material by tensile impact, as well as, to control the rate and other parameters of the loading impulse. Spall fracture is realized either by a collision of plates (Williams et al., 2012; Bie et al., 2015; Mokrushin et al., 2015) or performed on rod samples, modifying split Hopkinson pressure bar (SHPB) setup (Diaz-Rubio et al., 2002; Schuler and Hansson, 2006; Schuler et al., 2006; Kubota et al., 2008; Zhang et al., 2009; Li et al., 2017; Savinykh et al., 2019). This paper presents a method that allows predicting dynamic fracture in case of multiple spalling. The proposed model uses a structural-temporal approach which sets the fracture condition (Petrov and Utkin, 1989; Petrov and Morozov, 1994; Petrov, 2007). Application of this approach to predict fracture has shown good results (Petrov et al., 2010; Bragov et al., 2012, 2013; Evstifeev et al., 2018; Petrov and Kazarinov, 2018; Smirnov and Konstantinov, 2020) The aim of this work is to modelling fracture occurring in multiple locations. Multiple fracture can often be seen in Abstract The p per proposes a model that allows us to determine the fracture location in case of multiple spalling. The incubation time criterion was used to predict fracture in material. Modeling was performed for spall fracture performed on concrete rods. Com rison f the calculation results with experim ntal data was carri d ut which showed the coincidence of the predicted fractur zon with spall ctions in the samples. © 2020 The Aut ors. P bl shed by ELSEVIER B.V. This is an o en ac ess article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under espons bility of the uropean Structural Integrity Society (ESIS) ExCo Keywords: spall fracture, dynamic str ngth, incubation time, multiple spalling. 1. Introduction Material strength under dynamic impact is an urgent problem to this day. The high speed of the fracture process and its instability cause difficulties in the study of dynamic strength. In order to be able to control the process of dynamic fracture, as well as to use simplified formulations of problems in its modeling, special experimental techniques have been developed. Some of the most important of them are based on the phenomenon of spall fracture. This technique makes it possible to test the material by tensile impact, as well as, to control the rate and other parameters of the loading impulse. Spall fracture is realized either by a collision of plates (Williams et al., 2012; Bie et al., 2015; Mokrushin et al., 2015) or performed on rod samples, modifying split Hopkinson pressure bar (SHPB) setup (Diaz-Rubio et al., 2002; Schuler and Hansson, 2006; Schuler et al., 2006; Kubota et al., 2008; Zhang et al., 2009; Li et al., 2017; Savinykh et al., 2019). This paper presents a method that allows predicting dynamic fracture in case of multiple spalling. The proposed model uses a structural-temporal approach which sets the fracture condition (Petrov and Utkin, 1989; Petrov and Morozov, 1994; Petrov, 2007). Application of this approach to predict fracture has shown good results (Petrov et al., 2010; Bragov et al., 2012, 2013; Evstifeev et al., 2018; Petrov and Kazarinov, 2018; Smirnov and Konstantinov, 2020) The aim of this work is to modelling fracture occurring in multiple locations. Multiple fracture can often be seen in 1.

1 * Corresponding author. E-mail address: n.v.mikhailova@spbu.ru 1 * Corresponding author. E-mail address: n.v.mikhailova@spbu.ru

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.11.026 2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 2452-3216 © 2020 The Aut ors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo