PSI - Issue 65

ScienceDirect Structural Integrity Procedia 00 (2024) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2024) 000–000 Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 65 (2024) 102–108

The 17th International Conference on MECHANICS, RESOURCE AND DIAGNOSTICS OF MATERIALS AND STRUCTURES (MRDMS 2023) On complex deformations of underground pipelines in permafrost environment D.S. Ivanov a , G.S. Ammosov a , Z.G. Kornilova a, *, A.A. Antonov a a V.P. Larionov Institute of the Physical-Technical Problems of the North of the Siberian Branch of the RAS, Yakutsk, Russia, 677980,Oktyabrskaya str., 1. In the Northern regions, pipelines operate in extreme climatic and engineering-geological conditions. Permafrost soils affect the operational stability of the buried pipelines, causing their excessive wear . Frost heaving, as one of the most dangerous processes in the permafrost, can lead to tight bends in pipelines, sagging of individual sections, and displacements, sometimes with loss of stability. Our long-term annual monitoring of the underground pipeline has revealed sections with complex deformations in the form of several arches evolving into another without intervals. In six months, the gap in the high-altitude position reaches up to two meters. This article presents a method for assessing the stresses in the highly deformed sections of a pipeline. The obtained equation describes the vertical position of an underground pipeline, depending on the weight of the soil above and the reactions from below. We have used a numerical method to determine the soil response and the gradient descent method for its correction. © 2024 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 MRDMS 2023 organizers Keywords: complex deformations of the pipeline, planned-high-altitude position, underground pipeline, frost heaving, permafrost soil, gradient descent method. The 17th International Conference on MECHANICS, RESOURCE AND DIAGNOSTICS OF MATERIALS AND STRUCTURES (MRDMS 2023) On complex deformations of underground pipelines in permafrost environment D.S. Ivanov a , G.S. Ammosov a , Z.G. Kornilova a, *, A.A. Antonov a a V.P. Larionov Institute of the Physical-Technical Problems of the North of the Siberian Branch of the RAS, Yakutsk, Russia, 677980,Oktyabrskaya str., 1. Abstract In the Northern regions, pipelines operate in extreme climatic and engineering-geological conditions. Permafrost soils affect the operational stability of the buried pipelines, causing their excessive wear . Frost heaving, as one of the most dangerous processes in the permafrost, can lead to tight bends in pipelines, sagging of individual sections, and displacements, sometimes with loss of stability. Our long-term annual monitoring of the underground pipeline has revealed sections with complex deformations in the form of several arches evolving into another without intervals. In six months, the gap in the high-altitude position reaches up to two meters. This article presents a method for assessing the stresses in the highly deformed sections of a pipeline. The obtained equation describes the vertical position of an underground pipeline, depending on the weight of the soil above and the reactions from below. We have used a numerical method to determine the soil response and the gradient descent method for its correction. © 2024 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 MRDMS 2023 organizers Keywords: complex deformations of the pipeline, planned-high-altitude position, underground pipeline, frost heaving, permafrost soil, gradient descent method. © 2024 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 MRDMS 2023 organizers Abstract

* Corresponding author. Tel.: +7-914-225-8379. E-mail address: zoya_korn@mail.ru * Corresponding author. Tel.: +7-914-225-8379. E-mail address: zoya_korn@mail.ru

2452-3216 © 2024 D.S. Ivanov, G.S. Ammosov, Z.G. Kornilova, A.A. Antonov, 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 MRDMS 2023 organizers 2452-3216 © 2024 D.S. Ivanov, G.S. Ammosov, Z.G. Kornilova, A.A. Antonov, 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 MRDMS 2023 organizers

2452-3216 © 2024 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 MRDMS 2023 organizers 10.1016/j.prostr.2024.11.016