Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines.
Autor(a) principal: | |
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Data de Publicação: | 2021 |
Outros Autores: | , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFOP |
Texto Completo: | http://www.repositorio.ufop.br/jspui/handle/123456789/13905 https://doi.org/10.30486/GCR.2021.1908888.1033 |
Resumo: | Cave geotechnical studies have been the key to meeting the requirements of Brazilian environmental legislation for the conservation of speleological heritage in mining areas. This paper presents a methodology that classifies iron caves according to their susceptibility to structural instability called the Cave Geomechanical Index (CGI). This index combines four variables: (1) Rock Mass Rating (RMR), Bieniawski’ s geomechanical variable, which classifies the quality of the rock mass hosting the cave; (2) Hydraulic Radius (HR), an engineering variable that allows the dimension of the span to be evaluated; (3) Ceiling Shape (CS), a speleological variable that indicates whether the ceiling geometry of the cave spans is favorable or unfavorable for block formation, and (4) Ceiling Thickness (CT), a geotechnical variable that represents the depth between the ceiling of the cave and the surface of the ground regarding auto-support issues. The CGI was developed, applied and calibrated over four years, by monitoring 63 spans from 27 caves adjacent to active iron ore mines in Carajás, Pará state, Brazil, that had been authorized to be eliminated. This geomechanical classification system proved to be easy to implement and its results showed that 76% of the spans with breakdown occurrences in the caves were classified as high or very high susceptibility to structural instability, while 94% of the spans classified as low susceptibility did not show any signs of physical damage. The CGI is discussed with the focus on improving stability studies, predictability of cave breakdown mechanisms and geotechnical risk analysis of iron caves near mining operations. |
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Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines.Iron caveStability assessmentCave breakdownCave geomechanicsRisk analysisCave geotechnical studies have been the key to meeting the requirements of Brazilian environmental legislation for the conservation of speleological heritage in mining areas. This paper presents a methodology that classifies iron caves according to their susceptibility to structural instability called the Cave Geomechanical Index (CGI). This index combines four variables: (1) Rock Mass Rating (RMR), Bieniawski’ s geomechanical variable, which classifies the quality of the rock mass hosting the cave; (2) Hydraulic Radius (HR), an engineering variable that allows the dimension of the span to be evaluated; (3) Ceiling Shape (CS), a speleological variable that indicates whether the ceiling geometry of the cave spans is favorable or unfavorable for block formation, and (4) Ceiling Thickness (CT), a geotechnical variable that represents the depth between the ceiling of the cave and the surface of the ground regarding auto-support issues. The CGI was developed, applied and calibrated over four years, by monitoring 63 spans from 27 caves adjacent to active iron ore mines in Carajás, Pará state, Brazil, that had been authorized to be eliminated. This geomechanical classification system proved to be easy to implement and its results showed that 76% of the spans with breakdown occurrences in the caves were classified as high or very high susceptibility to structural instability, while 94% of the spans classified as low susceptibility did not show any signs of physical damage. The CGI is discussed with the focus on improving stability studies, predictability of cave breakdown mechanisms and geotechnical risk analysis of iron caves near mining operations.2021-11-12T14:09:24Z2021-11-12T14:09:24Z2021info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfBRANDI, I. V. et al. Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. Geoconservation Research, v. 3, n. 2, p. 134-161, jan. 2021. Disponível em: <http://www.iaujournals.ir/article_679230.html>. Acesso em: 12 set. 2021.2645-4661http://www.repositorio.ufop.br/jspui/handle/123456789/13905https://doi.org/10.30486/GCR.2021.1908888.1033This work is licensed under Creative Commons Attribution 4.0 License. Source: The article PDF.info:eu-repo/semantics/openAccessBrandi, Iuri VianaBarbosa, Marcelo RobertoSilva, Airton Barata daPaula, Rafael Guimarães deCorrea, TomasLima, Hernani Mota deOsborne, Robert Armstrongengreponame:Repositório Institucional da UFOPinstname:Universidade Federal de Ouro Preto (UFOP)instacron:UFOP2021-11-12T14:09:31Zoai:repositorio.ufop.br:123456789/13905Repositório InstitucionalPUBhttp://www.repositorio.ufop.br/oai/requestrepositorio@ufop.edu.bropendoar:32332021-11-12T14:09:31Repositório Institucional da UFOP - Universidade Federal de Ouro Preto (UFOP)false |
dc.title.none.fl_str_mv |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
title |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
spellingShingle |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. Brandi, Iuri Viana Iron cave Stability assessment Cave breakdown Cave geomechanics Risk analysis |
title_short |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
title_full |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
title_fullStr |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
title_full_unstemmed |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
title_sort |
Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. |
author |
Brandi, Iuri Viana |
author_facet |
Brandi, Iuri Viana Barbosa, Marcelo Roberto Silva, Airton Barata da Paula, Rafael Guimarães de Correa, Tomas Lima, Hernani Mota de Osborne, Robert Armstrong |
author_role |
author |
author2 |
Barbosa, Marcelo Roberto Silva, Airton Barata da Paula, Rafael Guimarães de Correa, Tomas Lima, Hernani Mota de Osborne, Robert Armstrong |
author2_role |
author author author author author author |
dc.contributor.author.fl_str_mv |
Brandi, Iuri Viana Barbosa, Marcelo Roberto Silva, Airton Barata da Paula, Rafael Guimarães de Correa, Tomas Lima, Hernani Mota de Osborne, Robert Armstrong |
dc.subject.por.fl_str_mv |
Iron cave Stability assessment Cave breakdown Cave geomechanics Risk analysis |
topic |
Iron cave Stability assessment Cave breakdown Cave geomechanics Risk analysis |
description |
Cave geotechnical studies have been the key to meeting the requirements of Brazilian environmental legislation for the conservation of speleological heritage in mining areas. This paper presents a methodology that classifies iron caves according to their susceptibility to structural instability called the Cave Geomechanical Index (CGI). This index combines four variables: (1) Rock Mass Rating (RMR), Bieniawski’ s geomechanical variable, which classifies the quality of the rock mass hosting the cave; (2) Hydraulic Radius (HR), an engineering variable that allows the dimension of the span to be evaluated; (3) Ceiling Shape (CS), a speleological variable that indicates whether the ceiling geometry of the cave spans is favorable or unfavorable for block formation, and (4) Ceiling Thickness (CT), a geotechnical variable that represents the depth between the ceiling of the cave and the surface of the ground regarding auto-support issues. The CGI was developed, applied and calibrated over four years, by monitoring 63 spans from 27 caves adjacent to active iron ore mines in Carajás, Pará state, Brazil, that had been authorized to be eliminated. This geomechanical classification system proved to be easy to implement and its results showed that 76% of the spans with breakdown occurrences in the caves were classified as high or very high susceptibility to structural instability, while 94% of the spans classified as low susceptibility did not show any signs of physical damage. The CGI is discussed with the focus on improving stability studies, predictability of cave breakdown mechanisms and geotechnical risk analysis of iron caves near mining operations. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-11-12T14:09:24Z 2021-11-12T14:09:24Z 2021 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
BRANDI, I. V. et al. Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. Geoconservation Research, v. 3, n. 2, p. 134-161, jan. 2021. Disponível em: <http://www.iaujournals.ir/article_679230.html>. Acesso em: 12 set. 2021. 2645-4661 http://www.repositorio.ufop.br/jspui/handle/123456789/13905 https://doi.org/10.30486/GCR.2021.1908888.1033 |
identifier_str_mv |
BRANDI, I. V. et al. Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines. Geoconservation Research, v. 3, n. 2, p. 134-161, jan. 2021. Disponível em: <http://www.iaujournals.ir/article_679230.html>. Acesso em: 12 set. 2021. 2645-4661 |
url |
http://www.repositorio.ufop.br/jspui/handle/123456789/13905 https://doi.org/10.30486/GCR.2021.1908888.1033 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
This work is licensed under Creative Commons Attribution 4.0 License. Source: The article PDF. info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
This work is licensed under Creative Commons Attribution 4.0 License. Source: The article PDF. |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFOP instname:Universidade Federal de Ouro Preto (UFOP) instacron:UFOP |
instname_str |
Universidade Federal de Ouro Preto (UFOP) |
instacron_str |
UFOP |
institution |
UFOP |
reponame_str |
Repositório Institucional da UFOP |
collection |
Repositório Institucional da UFOP |
repository.name.fl_str_mv |
Repositório Institucional da UFOP - Universidade Federal de Ouro Preto (UFOP) |
repository.mail.fl_str_mv |
repositorio@ufop.edu.br |
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1813002813918150656 |