<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Back in the early 1980s, coal deposits occurring at depths of ~700 m below surface were already regarded as large-depth deposits. Meanwhile, today the borderline depth of large-depth mining has extended to >1,000 m. Design, excavation and maintenance of mining roadways at the depth of >1,000 m have, therefore, become crucial issues in a practical perspective in recent years. Hence, it is now extremely important to intensify research studies on the influence of large depths on the behaviour of rock mass and deformation of support in underground excavations. The paper presents the results of the study carried out in five mining excavations at depths ranging from 950 to 1,290 m, where monitoring stations with measurement equipment were built. The analysis of data from laboratory and coal mine tests, as well as in situ monitoring, helped to formulate a set of criteria for stability assessment of underground excavations situated at large depths. The proposed methodology of load and deformation prediction in support systems of the excavations unaffected by exploitation is based on the criteria referring to the depth of excavation and the quality of rock mass. The depth parameter is determined by checking whether the analysed excavation lies below the critical depth, whereas the rock mass quality is determined on the basis of the roof lithology index (<italic>W<sub>L</sub></italic>) and the crack intensity factor (<italic>n</italic>)</p></abstract>

Back in the early 1980s, coal deposits occurring at depths of ~700 m below surface were already regarded as large-depth deposits. Meanwhile, today the borderline depth of large-depth mining has extended to >1,000 m. Design, excavation and maintenance of mining roadways at the depth of >1,000 m have, therefore, become crucial issues in a practical perspective in recent years. Hence, it is now extremely important to intensify research studies on the influence of large depths on the behaviour of rock mass and deformation of support in underground excavations. The paper presents the results of the study carried out in five mining excavations at depths ranging from 950 to 1,290 m, where monitoring stations with measurement equipment were built. The analysis of data from laboratory and coal mine tests, as well as in situ monitoring, helped to formulate a set of criteria for stability assessment of underground excavations situated at large depths. The proposed methodology of load and deformation prediction in support systems of the excavations unaffected by exploitation is based on the criteria referring to the depth of excavation and the quality of rock mass. The depth parameter is determined by checking whether the analysed excavation lies below the critical depth, whereas the rock mass quality is determined on the basis of the roof lithology index (WL) and the crack intensity factor (n)

Stability Assessment of Mining Excavations: the Impact of Large Depths

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

{"article-title":"Stability Assessment of Mining Excavations: the Impact of Large Depths"}

Back in the early 1980s, coal deposits occurring at depths of ~700 m below surface were already regarded as large-depth deposits. Meanwhile, today the...

Stability Assessment of Mining Excavations: the Impact of Large Depths

Article Category: Research Article

Published Online: Oct 24, 2018

Page range: 180 - 187

Received: Mar 21, 2018

Accepted: Jul 05, 2018

DOI: https://doi.org/10.2478/sgem-2018-0021

Keywords
great depth, coal mine roadway stability, underground in situ monitoring

© 2018 Tadeusz Majcherczyk et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Stability Assessment of Mining Excavations: the Impact of Large Depths

Article Category: Research Article

Published Online: Oct 24, 2018

Page range: 180 - 187

Received: Mar 21, 2018

Accepted: Jul 05, 2018

DOI: https://doi.org/10.2478/sgem-2018-0021

Keywordsgreat depth, coal mine roadway stability, underground in situ monitoring

© 2018 Tadeusz Majcherczyk et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
great depth, coal mine roadway stability, underground in situ monitoring