Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines

Artificial construction of a weakening zone over the roadway is an essential method for preventing coal bursts and rock bursts caused by strong mining tremors. However, concerning the seismic absorption and load reduction capabilities of an artificial structural weakening zone, the degree of rock ma...

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Main Authors: Jiaxin Zhuang, Zonglong Mu, Xiufeng Zhang, Wu Cai, Anye Cao, Chunlong Jiang, Piotr Małkowski
Format: Article
Language:English
Published: MDPI AG 2023-08-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/16/16/5958
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author Jiaxin Zhuang
Zonglong Mu
Xiufeng Zhang
Wu Cai
Anye Cao
Chunlong Jiang
Piotr Małkowski
author_facet Jiaxin Zhuang
Zonglong Mu
Xiufeng Zhang
Wu Cai
Anye Cao
Chunlong Jiang
Piotr Małkowski
author_sort Jiaxin Zhuang
collection DOAJ
description Artificial construction of a weakening zone over the roadway is an essential method for preventing coal bursts and rock bursts caused by strong mining tremors. However, concerning the seismic absorption and load reduction capabilities of an artificial structural weakening zone, the degree of rock mass damage to the roadway under weakening zone protection remains unclear. This study employed principles of elasticity and UDEC (Universal Distinct Element Code) to explore the seismic attenuation and load reduction capabilities of the weakening zone. The results indicate that the absorbing ability of the weakening zone increases exponentially with its weakening coefficient. Under the same dynamic load disturbance, when the weakening coefficient rises from 0.00 to 0.99, the sidewall displacement from the elastic wave source side changes from 0.400 m to 0.228 m. The total number of cracks in the roadway-surrounding rock, and the ranges of overstressed zones decreased linearly. The critical threshold of the roadway resisting the mining tremor disturbance increased. In particular, when the mining tremor is located directly above the roadway, the initial deformation of the roof is the largest, and the cumulative deformation of the rib is greater than the roof. By creating a weakening zone with a coefficient exceeding 0.95, the roadway remains unaffected by the 20 MPa dynamic loading. The study provides a theoretical basis for controlling coal burst that is triggered by mining tremors.
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spelling doaj.art-2efe5b83e0d0410a841559f32395fa5c2023-11-19T00:56:41ZengMDPI AGEnergies1996-10732023-08-011616595810.3390/en16165958Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal MinesJiaxin Zhuang0Zonglong Mu1Xiufeng Zhang2Wu Cai3Anye Cao4Chunlong Jiang5Piotr Małkowski6Jiangsu Engineering Laboratory of Mining Tremor Monitoring and Prevention, Xuzhou 221116, ChinaJiangsu Engineering Laboratory of Mining Tremor Monitoring and Prevention, Xuzhou 221116, ChinaShandong Energy Group Co., Ltd., Jinan 250014, ChinaJiangsu Engineering Laboratory of Mining Tremor Monitoring and Prevention, Xuzhou 221116, ChinaJiangsu Engineering Laboratory of Mining Tremor Monitoring and Prevention, Xuzhou 221116, ChinaJiangsu Engineering Laboratory of Mining Tremor Monitoring and Prevention, Xuzhou 221116, ChinaDepartment of Geomechanics, Civil Engineering and Geotechnics, Faculty of Civil Engineering and Resource Management, AGH University of Science and Technology, 30-059 Krakow, PolandArtificial construction of a weakening zone over the roadway is an essential method for preventing coal bursts and rock bursts caused by strong mining tremors. However, concerning the seismic absorption and load reduction capabilities of an artificial structural weakening zone, the degree of rock mass damage to the roadway under weakening zone protection remains unclear. This study employed principles of elasticity and UDEC (Universal Distinct Element Code) to explore the seismic attenuation and load reduction capabilities of the weakening zone. The results indicate that the absorbing ability of the weakening zone increases exponentially with its weakening coefficient. Under the same dynamic load disturbance, when the weakening coefficient rises from 0.00 to 0.99, the sidewall displacement from the elastic wave source side changes from 0.400 m to 0.228 m. The total number of cracks in the roadway-surrounding rock, and the ranges of overstressed zones decreased linearly. The critical threshold of the roadway resisting the mining tremor disturbance increased. In particular, when the mining tremor is located directly above the roadway, the initial deformation of the roof is the largest, and the cumulative deformation of the rib is greater than the roof. By creating a weakening zone with a coefficient exceeding 0.95, the roadway remains unaffected by the 20 MPa dynamic loading. The study provides a theoretical basis for controlling coal burst that is triggered by mining tremors.https://www.mdpi.com/1996-1073/16/16/5958mining tremorsdynamic load on rocksweakening zoneelastic wave attenuationsurrounding rock damagerock burst hazard
spellingShingle Jiaxin Zhuang
Zonglong Mu
Xiufeng Zhang
Wu Cai
Anye Cao
Chunlong Jiang
Piotr Małkowski
Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines
Energies
mining tremors
dynamic load on rocks
weakening zone
elastic wave attenuation
surrounding rock damage
rock burst hazard
title Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines
title_full Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines
title_fullStr Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines
title_full_unstemmed Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines
title_short Seismic Mitigation Effect of Overlying Weakening Strata in Underground Coal Mines
title_sort seismic mitigation effect of overlying weakening strata in underground coal mines
topic mining tremors
dynamic load on rocks
weakening zone
elastic wave attenuation
surrounding rock damage
rock burst hazard
url https://www.mdpi.com/1996-1073/16/16/5958
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