PSI - Issue 32

Available online at www.sciencedirect.com Available online at www.sciencedirect.com Sci nceD rect Structural Integrity Procedia 00 (2021) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2021) 000–000

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Procedia Structural Integrity 32 (2021) 3–9

© 2021 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 XXIIth Winter School on Continuous Media Mechanics” Abstract This article discusses the effect of explosion pulse on the process of cracking in a rock mass and shows the possibility of calculating the radius of a cracking zone by the theoretical value of the dynamic strength of rocks, based on their main physical and mechanical characteristics. © 2021 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 XXIIth Winter School on Continuous Media Mechanics” Keywords: explosion pulse; strain; damping; strength; radius of a crack formation zone; radial clearance 1. Introduction When driving mine workings in outburst-hazardous rocks, the rock mass in front of the face is torpedoed to a certain predetermined depth to bring this rock mass into a safe state [1]. Torpedoing is performed with elongated explosive (E) charges in order to create a continuous crack zone over a section exceeding the section of the mine and providing degassing of outburst-hazardous rocks. To calculate the parameters of torpedoing, it is necessary to estimate the radius of the cracks around a single torpedo charge. The importance and responsibility of these works leads to the need to determine the value of this radius by experimental blasting. However, when conducting experimental blasting, it is required to precalculate the value of the crack zone radius, and, in some cases, it is necessary to focus only on the reference values of this quantity. Despite the existence of a number of fundamental works on this issue, the problem of engineering calculations of the crack radius with an elongated charge remains urgent [2-5]. Abstract This article discusses the effect of explosion pulse on the process of cracking in a rock mass and shows the possibility of calculating th radi s of a cracking zon by the theor tical value f the dyn mic strength of rocks, based n their main physical and mechanical characteristics. © 2021 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 u der re ponsibility of scientific committe of the XXIIth Winter School on Continuous Media Mechanics” Keywords: explosion pulse; strain; damping; strength; radius of a crack formation zone; radial clearance 1. Introduction When driving mine workings in outburst-hazardous rocks, the rock mass in front of the face is torpedoed to a certain predetermined depth to br g this ock mass into a safe state [1]. Torpedoi g is performed with el ngated explosive (E) charg s in order to create a continuou crack zone over a section exceeding th section of e mi e an provid ng degassing of utburst-hazardous rocks. To alculate the paramet rs of torpedoing, it is necessary to estimate the radius of the crack aroun a ingle torpedo charg . The importance and responsibil y of these works leads o t need t d termine the value of this ra ius by xperimental blasti g. However, when conducting experimental blasting, it is required to pr calculate the value of the crack zone radius, and, in some ases, it is nec ssary o focu only on th ref rence values of his quantity. Despite the existence of umber of fundamental work on his issue, the probl m of engineering calculatio s of the crack radius with an elongat d charge re ains urgent [2-5]. XXIIth Winter School on Continuous Media Mechanics Calculation of crack formation radius by modeling the explosive charge with a radial clearance S.S. Andreiko,V.M. Maltsev,V.V. Anikin*, Е.А. Nesterov XXIIth Winter School on Continuous Media Mechanics Calculation of crack formation radius by modeling the explosive charge with a radial clearance S.S. Andreiko,V.M. Maltsev,V.V. Anikin*, Е.А. Nesterov Mining Institute Ural Branch Russian Academy of Sciences, Sibirskaya str., 78-a , Perm, 614007, Russia Mining Institute Ural Branch Russian Academy of Sciences, Sibirskaya str., 78-a , Perm, 614007, Russia

* Corresponding author. Tel.: +7-961-754-33-69; fax: +7-342-216-75-02. E-mail address: anikin-59@yandex.ru * Corresponding author. Tel.: +7-961-754-33-69; fax: +7-342-216-75-02. E-mail address: anikin-59@yandex.ru

2452-3216© 2021 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 XXIIth Winter School on Continuous Media Mechanics” 2452-3216© 2021 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 u der responsibility of t e scientific committee of the XXIIth Winter School on Continuous Media Mechanics”

2452-3216 © 2021 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 XXIIth Winter School on Continuous Media Mechanics” 10.1016/j.prostr.2021.09.002