Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines

With the steady increase in the size, intensification, and modernization of coal production enterprises, the deep coal resources in large coal bases are gradually entering the mining stage. When the coal mining reaches the deep zone, the interactions between various underground dynamic hazards begin...

Full description

Saved in:
Bibliographic Details
Main Authors: Haitao Sun, Linchao Dai, Yanbao Liu, Hongwei Jin
Format: Article
Language:English
Published: Wiley 2021-01-01
Series:Geofluids
Online Access:http://dx.doi.org/10.1155/2021/6655443
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832568582903431168
author Haitao Sun
Linchao Dai
Yanbao Liu
Hongwei Jin
author_facet Haitao Sun
Linchao Dai
Yanbao Liu
Hongwei Jin
author_sort Haitao Sun
collection DOAJ
description With the steady increase in the size, intensification, and modernization of coal production enterprises, the deep coal resources in large coal bases are gradually entering the mining stage. When the coal mining reaches the deep zone, the interactions between various underground dynamic hazards begin to occur. These interactions are affected by the engineering geological environment and can lead to the occurrence of severe compound hazards. When coal and gas outbursts occur and destabilize the mining area, the high geostress causes the multiphysical coupling effect of the laminated overburden system to become more pronounced. Therefore, we analyzed the development path of a coal-rock system under instability conditions from the perspective of coal–rock coupling, constructed a model of the coal-rock combination system’s structure, and proposed three directions (i.e., strain softening, limit equilibrium, and dynamic instability) for the development of coal-rock system instability. Then, we established a model for the critical conditions of the system’s failure process and elucidated that the release of the rock’s elastic energy promoted the instability of the coal. Furthermore, we verified the established critical conditions through laboratory tests on a coal-rock combination structure and obtained the patterns of the rock energy transferring into the coal seam during the instability failure process of the coal–rock combination structure. When the coal–rock combination structure failed, the rock strain reached its maximum value and the strain rebound phenomenon occurred. The stored elastic strain energy released by the rock into the combination system accounted for 26% to 53% of the accumulated energy in the rock itself, and the released elastic energy and the new surface area of the crushed coal sample followed a logarithmic relationship. The findings of this study provide theoretical support for the identification and quantitative analysis of instability due to the dynamic hazards of coal-rock gas in deep mines.
format Article
id doaj-art-895143a317b149268a8665b2d2fd0130
institution Kabale University
issn 1468-8115
1468-8123
language English
publishDate 2021-01-01
publisher Wiley
record_format Article
series Geofluids
spelling doaj-art-895143a317b149268a8665b2d2fd01302025-02-03T00:58:50ZengWileyGeofluids1468-81151468-81232021-01-01202110.1155/2021/66554436655443Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep MinesHaitao Sun0Linchao Dai1Yanbao Liu2Hongwei Jin3State Key Laboratory of the Gas Disaster Detecting, Preventing and Emergency Controlling, Chongqing 400037, ChinaState Key Laboratory of the Gas Disaster Detecting, Preventing and Emergency Controlling, Chongqing 400037, ChinaState Key Laboratory of the Gas Disaster Detecting, Preventing and Emergency Controlling, Chongqing 400037, ChinaSchool of Safety Engineering, Xi’an University of Science and Technology, Xi’an, Shanxi 710054, ChinaWith the steady increase in the size, intensification, and modernization of coal production enterprises, the deep coal resources in large coal bases are gradually entering the mining stage. When the coal mining reaches the deep zone, the interactions between various underground dynamic hazards begin to occur. These interactions are affected by the engineering geological environment and can lead to the occurrence of severe compound hazards. When coal and gas outbursts occur and destabilize the mining area, the high geostress causes the multiphysical coupling effect of the laminated overburden system to become more pronounced. Therefore, we analyzed the development path of a coal-rock system under instability conditions from the perspective of coal–rock coupling, constructed a model of the coal-rock combination system’s structure, and proposed three directions (i.e., strain softening, limit equilibrium, and dynamic instability) for the development of coal-rock system instability. Then, we established a model for the critical conditions of the system’s failure process and elucidated that the release of the rock’s elastic energy promoted the instability of the coal. Furthermore, we verified the established critical conditions through laboratory tests on a coal-rock combination structure and obtained the patterns of the rock energy transferring into the coal seam during the instability failure process of the coal–rock combination structure. When the coal–rock combination structure failed, the rock strain reached its maximum value and the strain rebound phenomenon occurred. The stored elastic strain energy released by the rock into the combination system accounted for 26% to 53% of the accumulated energy in the rock itself, and the released elastic energy and the new surface area of the crushed coal sample followed a logarithmic relationship. The findings of this study provide theoretical support for the identification and quantitative analysis of instability due to the dynamic hazards of coal-rock gas in deep mines.http://dx.doi.org/10.1155/2021/6655443
spellingShingle Haitao Sun
Linchao Dai
Yanbao Liu
Hongwei Jin
Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines
Geofluids
title Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines
title_full Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines
title_fullStr Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines
title_full_unstemmed Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines
title_short Critical Conditions and Energy Transfer Characteristics of the Failure Process of Coal-Rock Combination Systems in Deep Mines
title_sort critical conditions and energy transfer characteristics of the failure process of coal rock combination systems in deep mines
url http://dx.doi.org/10.1155/2021/6655443
work_keys_str_mv AT haitaosun criticalconditionsandenergytransfercharacteristicsofthefailureprocessofcoalrockcombinationsystemsindeepmines
AT linchaodai criticalconditionsandenergytransfercharacteristicsofthefailureprocessofcoalrockcombinationsystemsindeepmines
AT yanbaoliu criticalconditionsandenergytransfercharacteristicsofthefailureprocessofcoalrockcombinationsystemsindeepmines
AT hongweijin criticalconditionsandenergytransfercharacteristicsofthefailureprocessofcoalrockcombinationsystemsindeepmines