Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof

Hydraulic fracturing technology is one of the effective methods for weakening the roof of coal mines and preventing rockburst. This article takes the 2305 thick coal seam fully mechanized caving working face of a coal mine in Shaanxi Province as the engineering background, and uses theoretical analy...

Full description

Saved in:
Bibliographic Details
Main Authors: Yi TAN, Yu WANG, Manchao HE, Hui LI, Wenbing GUO, Linmao LI, Weidong LIU, Shaopu ZHANG
Format: Article
Language:zho
Published: Editorial Office of Journal of China Coal Society 2025-02-01
Series:Meitan xuebao
Subjects:
Online Access:http://www.mtxb.com.cn/article/doi/10.13225/j.cnki.jccs.2024.1044
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850152167348895744
author Yi TAN
Yu WANG
Manchao HE
Hui LI
Wenbing GUO
Linmao LI
Weidong LIU
Shaopu ZHANG
author_facet Yi TAN
Yu WANG
Manchao HE
Hui LI
Wenbing GUO
Linmao LI
Weidong LIU
Shaopu ZHANG
author_sort Yi TAN
collection DOAJ
description Hydraulic fracturing technology is one of the effective methods for weakening the roof of coal mines and preventing rockburst. This article takes the 2305 thick coal seam fully mechanized caving working face of a coal mine in Shaanxi Province as the engineering background, and uses theoretical analysis, numerical simulation, on-site testing, and engineering monitoring methods to study the weakening control technology of the hard roof area. Based on the theory of “plastic stranded wire”, a mechanical model of the basic top “thin plate structure” is constructed, and a method is proposed to determine the hydraulic fracturing target layer by combining the accumulated bending strain energy and the distribution and response characteristics of high-energy microseismic events at the critical state of the first fracture of the hard top plate in the coal seam extraction process. According to this method, the fracturing target layer of 2305 working face is determined to be 14.50 m thick coarse sandstone; A numerical calculation model for strain softening under fluid structure coupling mode was constructed, and a comparative experiment was designed with and without directional segmented hydraulic fracturing in the target layer. The strength stress ratio parameter was introduced to analyze the local stability of the roof. The results showed that directional long drilling hydraulic fracturing effectively broke the integrity of the basic roof and shortened the step distance of the basic roof. The initial step distance was reduced by 25.81%, and the periodic step distance was reduced by 24.64%, reducing the possibility of forming huge dynamic loads and inducing impact ground pressure due to the large suspended area of the roof; Based on the geological conditions of the 2305 working face, a multi-dimensional segmented hydraulic fracturing construction plan combining directional long drilling and conventional shallow drilling was designed. During the fracturing process of directional long drilling holes No.20, No.21, and No.22, there were 30, 35, and 23 instances of pressure drop above 3 MPa, respectively. The directional segmented hydraulic fracturing caused damage to the integrity of the roof. During the conventional shallow drilling fracturing process, the expansion forms of different fractures showed different stage characteristics of two-stage stability and multi-stage development on the fracturing curve. The fracturing effect of the roof and top coal was significant; Multiple monitoring methods were used to monitor the surrounding rock activity of the 2305 working face. The implementation of multi-dimensional segmented hydraulic fracturing technology destroyed the integrity of the hard roof. Compared with the 2303 working face without hydraulic fracturing, the initial and periodic pressure step distances were reduced by 24 m and 12 m, respectively, with a reduction of 33.33% and 32.19%, effectively reducing the working resistance of the mining face support and reducing the possibility of high-energy microseismic events, providing a guarantee for underground safety production.
format Article
id doaj-art-c0462d43bc4e44e68da8dda2fb23141c
institution OA Journals
issn 0253-9993
language zho
publishDate 2025-02-01
publisher Editorial Office of Journal of China Coal Society
record_format Article
series Meitan xuebao
spelling doaj-art-c0462d43bc4e44e68da8dda2fb23141c2025-08-20T02:26:03ZzhoEditorial Office of Journal of China Coal SocietyMeitan xuebao0253-99932025-02-0150279480910.13225/j.cnki.jccs.2024.10442024-1044Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roofYi TAN0Yu WANG1Manchao HE2Hui LI3Wenbing GUO4Linmao LI5Weidong LIU6Shaopu ZHANG7School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, ChinaSchool of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, ChinaSchool of Earth Sciences and Engineering, Hehai University, Nanjing 210098, ChinaSchool of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, ChinaSchool of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, ChinaShaanxi Cuijiagou Energy Corporation, Tongchuan 727000, ChinaKailuan Mining Engineering Corporation Shaanxi Tongchuan Branch, Tongchuan 727000, ChinaSchool of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, ChinaHydraulic fracturing technology is one of the effective methods for weakening the roof of coal mines and preventing rockburst. This article takes the 2305 thick coal seam fully mechanized caving working face of a coal mine in Shaanxi Province as the engineering background, and uses theoretical analysis, numerical simulation, on-site testing, and engineering monitoring methods to study the weakening control technology of the hard roof area. Based on the theory of “plastic stranded wire”, a mechanical model of the basic top “thin plate structure” is constructed, and a method is proposed to determine the hydraulic fracturing target layer by combining the accumulated bending strain energy and the distribution and response characteristics of high-energy microseismic events at the critical state of the first fracture of the hard top plate in the coal seam extraction process. According to this method, the fracturing target layer of 2305 working face is determined to be 14.50 m thick coarse sandstone; A numerical calculation model for strain softening under fluid structure coupling mode was constructed, and a comparative experiment was designed with and without directional segmented hydraulic fracturing in the target layer. The strength stress ratio parameter was introduced to analyze the local stability of the roof. The results showed that directional long drilling hydraulic fracturing effectively broke the integrity of the basic roof and shortened the step distance of the basic roof. The initial step distance was reduced by 25.81%, and the periodic step distance was reduced by 24.64%, reducing the possibility of forming huge dynamic loads and inducing impact ground pressure due to the large suspended area of the roof; Based on the geological conditions of the 2305 working face, a multi-dimensional segmented hydraulic fracturing construction plan combining directional long drilling and conventional shallow drilling was designed. During the fracturing process of directional long drilling holes No.20, No.21, and No.22, there were 30, 35, and 23 instances of pressure drop above 3 MPa, respectively. The directional segmented hydraulic fracturing caused damage to the integrity of the roof. During the conventional shallow drilling fracturing process, the expansion forms of different fractures showed different stage characteristics of two-stage stability and multi-stage development on the fracturing curve. The fracturing effect of the roof and top coal was significant; Multiple monitoring methods were used to monitor the surrounding rock activity of the 2305 working face. The implementation of multi-dimensional segmented hydraulic fracturing technology destroyed the integrity of the hard roof. Compared with the 2303 working face without hydraulic fracturing, the initial and periodic pressure step distances were reduced by 24 m and 12 m, respectively, with a reduction of 33.33% and 32.19%, effectively reducing the working resistance of the mining face support and reducing the possibility of high-energy microseismic events, providing a guarantee for underground safety production.http://www.mtxb.com.cn/article/doi/10.13225/j.cnki.jccs.2024.1044extra-thick coal seamhard stratumplastic mechanicshydraulic fracturingseismic monitoring.
spellingShingle Yi TAN
Yu WANG
Manchao HE
Hui LI
Wenbing GUO
Linmao LI
Weidong LIU
Shaopu ZHANG
Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
Meitan xuebao
extra-thick coal seam
hard stratum
plastic mechanics
hydraulic fracturing
seismic monitoring.
title Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
title_full Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
title_fullStr Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
title_full_unstemmed Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
title_short Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
title_sort multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof
topic extra-thick coal seam
hard stratum
plastic mechanics
hydraulic fracturing
seismic monitoring.
url http://www.mtxb.com.cn/article/doi/10.13225/j.cnki.jccs.2024.1044
work_keys_str_mv AT yitan multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT yuwang multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT manchaohe multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT huili multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT wenbingguo multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT linmaoli multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT weidongliu multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof
AT shaopuzhang multidimensionalsegmentedhydraulicfracturingimpactgroundpressurecontrolandlossreductiontechnologyfordeepburiedthickcoalseamhardroof