Numerical simulation of grout diffusion under coal seam floor and analysis of influencing factors

Authors

GUO Yan, CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China; Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard, Xi’an 710077, China; National Coal Mine Water Hazard Prevention Engineering Technology Research Center, Suzhou University, Suzhou 234000, China; School of Earth and Space Sciences, University of Science and Technology of China, Hefei 232000, ChinaFollow
GUI Herong, National Coal Mine Water Hazard Prevention Engineering Technology Research Center, Suzhou University, Suzhou 234000, ChinaFollow
WEI Jiuchuan, College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao 266590, China
HONG Huang, Anhui Hengyuan Coal Power Co. Ltd., Huaibei 235000, China
GUO Xiangdong, National Coal Mine Water Hazard Prevention Engineering Technology Research Center, Suzhou University, Suzhou 234000, China
CUI Yali, College of Energy Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
YE Shuang
LI Jun, National Coal Mine Water Hazard Prevention Engineering Technology Research Center, Suzhou University, Suzhou 234000, China; School of Earth and Space Sciences, University of Science and Technology of China, Hefei 232000, China

Abstract

Ground high-pressure advanced regional grouting has become the preferred engineering method for the prevention and control of water disasters in coal mines. The diffusion mechanism of grout has received widespread attention, and the design of branch hole spacing mostly relies on the on-site experience, which has a certain degree of blindness and restricts the effectiveness and efficiency of the project. Based on the actual working conditions of grouting site in Hengyuan Coal Mine, Huaibei Coalfield, the numerical simulation was performed with the COMSOL Multiphysics software for the high-pressure grout diffusion in the floor area of the ground directional drilling coal seam, the influencing factors of grout diffusion were analyzed, and the mechanism of ground high-pressure grout diffusion was discussed. The results are as follows: (1) Fractures are developed in the third thin layer of limestone in the Carboniferous Taiyuan Formation (hereinafter referred to as “the third limestone layer”) of the coal seam floor. It is found through simulation that the fracturing effect is likely to occur during 8-12 MPa high-pressure grouting, during which the permeability coefficient increases by about 4 orders of magnitude. (2) Without considering the influence of gravity, the grout diffusion distance to the periphery is equal with the branch hole as the center, and the grout density is large near the branch hole, with the volume fraction more than 0.2. When the gravity is considered, the horizontal grout diffusion range is relatively increased, and the grout mainly diffuses downward vertically, which is “short up and long down”. (3) The grout diffusion simulation shows that the diffusion range is 41.2 m. Definitely, the field grout diffusion range is measured to be 38.3-44.0 m, which verifies the correctness of the grout diffusion model. (4) The range of grout diffusion is negatively correlated with the relative density, hydrostatic pressure, dynamic viscosity, yield strength and porosity of grout, and positively correlated with the width of fracture and permeability coefficient. Specifically, the smaller the relative density of grout is, the more obvious the response of its diffusion range is. With the increase of dynamic viscosity, the diffusion range decreases more and more slowly. The research results could provide a reference for the reasonable design of the grouting treatment project in the water hazard area of the coal measures floor, with good reference and application value.

Keywords

directional drilling, high pressure grouting, grout diffusion range, grout diffusion mechanism

DOI

10.12363/issn.1001-1986.22.12.0963

Recommended Citation

GUO Yan, GUI Herong, WEI Jiuchuan, et al. (2023) "Numerical simulation of grout diffusion under coal seam floor and analysis of influencing factors," Coal Geology & Exploration: Vol. 51: Iss. 6, Article 5.
DOI: 10.12363/issn.1001-1986.22.12.0963
Available at: https://cge.researchcommons.org/journal/vol51/iss6/5

Reference

[1] 刘光军,岳祁,金国明. 基于数值模拟的劈裂注浆浆液扩散范围分析[J]. 路基工程,2019(6):103−107.

LIU Guangjun,YUE Qi,JIN Guoming. Analysis on diffusion scope of fracture grouting slurry based on numerical simulation[J]. Subgrade Engineering,2019(6):103−107.

[2] 余伟健,吴根水,安百富,等. 裂隙岩体巷道大变形特征与稳定性控制[J]. 采矿与安全工程学报,2019,36(1):103−111.

YU Weijian,WU Genshui,AN Baifu,et al. Large deformation characteristics and stability control of roadway with fractured rock mass[J]. Journal of Mining & Safety Engineering,2019,36(1):103−111.

[3] 杨米加,陈明雄,贺永年. 注浆理论的研究现状及发展方向[J]. 岩石力学与工程学报,2001,20(6):839−841.

YANG Mijia,CHEN Mingxiong,HE Yongnian. Current research state of grouting technology and its development direction in future[J]. Chinese Journal of Rock Mechanics and Engineering,2001,20(6):839−841.

[4] 刘健,刘人太,张霄,等. 水泥浆液裂隙注浆扩散规律模型试验与数值模拟[J]. 岩石力学与工程学报,2012,31(12):2445−2452.

LIU Jian,LIU Rentai,ZHANG Xiao,et al. Diffusion law model test and numerical simulation of cement fracture grouting[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(12):2445−2452.

[5] GUO Yan,WEI Jiuchuan,GUI Herong,et al. Evaluation of changes in groundwater quality caused by a water inrush event in Taoyuan Coal Mine,China[J]. Environmental Earth Sciences,2020,79(24):528.

[6] GUO Yan,GUI Herong,WEI Jiuchuan,et al. Hydrogeochemistry of water in coal measures during grouting treatment of Taoyuan Mine,China[J]. Groundwater,2021,59(2):256−265.

[7] 郑士田. 两淮煤田煤层底板灰岩水害区域超前探查治理技术[J]. 煤田地质与勘探,2018,46(4):142−146.

ZHENG Shitian. Advanced exploration and control technology of limestone water hazard in coal seam floor in Huainan and Huaibei Coalfields[J]. Coal Geology & Exploration,2018,46(4):142−146.

[8] 虎维岳,赵春虎,吕汉江. 煤层底板水害区域注浆治理影响因素分析与高效布孔方式[J]. 煤田地质与勘探,2022,50(11):134−143.

HU Weiyue,ZHAO Chunhu,LYU Hanjiang. Main influencing factors for regional pre−grouting technology of water hazard treatment in coal seam floor and efficient hole arrangement[J]. Coal Geology & Exploration,2022,50(11):134−143.

[9] 谢龙,张德兵,梁顺. 回采巷道注浆锚索超前支护优化及效果模拟[J]. 采矿与岩层控制工程学报,2022,4(3):033011.

XIE Long,ZHANG Debing,LIANG Shun. Optimisation and simulation of the effect of grouted cable bolts as advanced support in longwall entries[J]. Journal of Mining and Strata Control Engineering,2022,4(3):033011.

[10] 毛宏远. 吕家坨矿深部巷道中空注浆锚索加固研究与应用[D]. 邯郸：河北工程大学，2019.

MAO Hongyuan. Research and application of hollow grouting anchor cable reinforcement in deep roadway of Lyujiatuo Mine[D]. Handan：Hebei University of Engineering，2019.

[11] 王东亮,郝兵元,梁晓敏. 基于流固耦合的单一裂隙浆液扩散规律研究[J]. 采矿与岩层控制工程学报,2021,3(1):013038.

WANG Dongliang,HAO Bingyuan,LIANG Xiaomin. Slurry diffusion of single fracture based on fluid−solid coupling[J]. Journal of Mining and Strata Control Engineering,2021,3(1):013038.

[12] 李昂，李远谋，姬亚东，等. 煤矿多孔骨料注浆截流试验机理研究[J/OL]. 煤炭科学技术，2023：1–9[2023-05-30]. Doi：10.13199/j.cnki.cst.2022–1471.

LI Ang，LI Yuanmou，JI Yadong，et al. Research on the experimental mechanism of grouting and interception of porous aggregate in coal mine[J]. Coal Science and Technology，2023：1–9[2023-05-30]. Doi：10.13199/j.cnki.cst.2022–1471.

[13] 景锋，韩炜，赵青，等. 高水头下环氧浆液渗透扩散机理流固耦合数值模拟研究[C]//2019水利水电地基与基础工程新技术——中国水利学会地基与基础工程专业委员会第15次全国学术会议论文集. 昆明，2019：27–33.

[14] 魏久传,韩承豪,张伟杰,等. 基于步进式算法的裂隙注浆扩散机制研究[J]. 岩土力学,2019,40(3):913−925.

WEI Jiuchuan,HAN Chenghao,ZHANG Weijie,et al. Mechanism of fissure grouting based on step–wise calculation method[J]. Rock and Soil Mechanics,2019,40(3):913−925.

[15] 胡洋. 煤矿裂隙含水层驱水注浆机制研究[D]. 徐州：中国矿业大学，2020.

HU Yang. Research on mechanism of water–displacing grouting in mine fractured aquifer[D]. Xuzhou：China University of Mining and Technology，2020.

[16] 李术才,郑卓,刘人太,等. 考虑浆–岩耦合效应的微裂隙注浆扩散机制分析[J]. 岩石力学与工程学报,2017,36(4):812−820.

LI Shucai,ZHENG Zhuo,LIU Rentai,et al. Analysis on fracture grouting mechanism considering grout−rock coupling effect[J]. Chinese Journal of Rock Mechanics and Engineering,2017,36(4):812−820.

[17] 谷拴成,孙冠临,苏培莉,等. 岩体裂隙动水注浆扩散半径影响试验[J]. 煤田地质与勘探,2019,47(5):144−149.

GU Shuancheng,SUN Guanlin,SU Peili,et al. Test of the influence of dynamic water grouting diffusion radius of fractures in rock[J]. Coal Geology & Exploration,2019,47(5):144−149.

[18] 黄润秋,王贤能,陈龙生. 深埋隧道涌水过程的水力劈裂作用分析[J]. 岩石力学与工程学报,2000,19(5):573−576.

HUANG Runqiu,WANG Xianneng,CHEN Longsheng. Hydro–splitting off analysis on underground water in deep–lying tunnels and its effect on water gushing out[J]. Chinese Journal of Rock Mechanics and Engineering,2000,19(5):573−576.

[19] 张铁富,杨庆国,易志坚,等. 水压力对砼面板板底裂纹的劈裂作用和数值模拟[J]. 重庆交通大学学报(自然科学版),2007,26(5):61−63.

ZHANG Tiefu,YANG Qingguo,YI Zhijian,et al. Fracture mechanism and simulation of cracks on the bottom of concrete slab under water pressure effect[J]. Journal of Chongqing Jiaotong University (Natural Science),2007,26(5):61−63.

[20] 韩磊,陈建生,陈亮. 帷幕灌浆扩散半径及数值模拟的研究[J]. 岩土力学,2012,33(7):2235−2240.

HAN Lei,CHEN Jiansheng,CHEN Liang. Research on diffusion radius and numerical simulation in curtain grouting[J]. Rock and Soil Mechanics,2012,33(7):2235−2240.

[21] 张良辉,熊厚金,张清. 浆液的非稳定渗流过程分析[J]. 岩石力学与工程学报,1997,16(6):564−570.

ZHANG Lianghui,XIONG Houjin,ZHANG Qing. Analyses of the unsteady permeation process of grout[J]. Chinese Journal of Rock Mechanics and Engineering,1997,16(6):564−570.

[22] NGHIEM L，COLLINS D A，SHARMA R. Seventh SPE comparative solution project：Modelling of horizontal wells in reservoir simulation[C]//The 11th SPE Symposium on Reservoir Simulation. Anaheim，1991：195–218.

[23] 杨文才. 基于浆液自重的多孔介质渗透注浆机制研究[D]. 昆明：昆明理工大学，2020.

YANG Wencai. Study on mechanism of porous media infiltration grouting based on self weight of grout[D]. Kunming：Kunming University of Science and Technology，2020.