PSI - Issue 42

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 42 (2022) 420–424

© 2022 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 scientific committee of the 23 European Conference on Fracture – ECF23 Abstract Instability of theoretical rate dependencies of the stress intensity factor and fracture energy is considered from the point of view of force and energy limiting criteria formulated on the basis of the concepts of the structural-temporal approach. Applying both approaches separately, the water saturation effect on dynamic stress intensity factor and dynamic fracture energy is predicted. Using the dynamic fracture of sandstone as an example, the incubation times as a characteristic of the rate sensitivity of the material determined by the force and energy fracture are compared. © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23 Keywords: Fracture toughness, incubation time, fracture energy 1. Introduction In dynamic three-point bending tests on notched semi-circular bend specimens (Zhang and Zhao (2013), Chen et al. (2009), Gao et al. (2015)), the stress intensity factor depending on fracture toughness rate is increased. In these studies (Zhang and Zhao (2013), Chen et al. (2009), Gao et al. (2015)) the influence of hydrostatic pressure (Yao et al. (2019)), and water saturation (Zhang and Zhao (2014)) on dynamic stress intensity factor relative to static one is discussed. Unlike static experiments where static fracture toughness is a property of the material and a constant value, dynamic stress intensity factor depends on the loading history. In (Kazarinov et al. 2021), analytical results r nd 23 European Conference on Fracture - ECF23 Structural-temporal peculiarities of dynamic deformation of rock Nina Selyutina a, * a Saint Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg, 199034, Russia

* Corresponding author. E-mail address: nina.selutina@gmail.com

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of 23 European Conference on Fracture - ECF23

2452-3216 © 2022 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 scientific committee of the 23 European Conference on Fracture – ECF23 10.1016/j.prostr.2022.12.053