Cave Geomechanical Index (CGI). classification and contribution to the conservation of natural caves in the iron mines.

Detalhes bibliográficos
Autor(a) principal: Brandi, Iuri Viana
Data de Publicação: 2021
Outros Autores: Barbosa, Marcelo Roberto, Silva, Airton Barata da, Paula, Rafael Guimarães de, Correa, Tomas, Lima, Hernani Mota de, Osborne, Robert Armstrong
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.
id UFOP_cec085cb5f8a569d238cf53383ac97b0
oai_identifier_str oai:repositorio.ufop.br:123456789/13905
network_acronym_str UFOP
network_name_str Repositório Institucional da UFOP
repository_id_str 3233
spelling 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
_version_ 1813002813918150656