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Table Of Contents, The Editors Dec 2023

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Optimization Of Data Acquisition Parameters For Deep Seismic Reflection Surveys In Complex Terrain, Yan Yunxiang, Li Pei, Zhi Min, Liu Jianda, Wang Zichen, Zhang Ying, Pei Gendi, Li Linyuan, Mou Qi, Jia Jin Dec 2023

Optimization Of Data Acquisition Parameters For Deep Seismic Reflection Surveys In Complex Terrain, Yan Yunxiang, Li Pei, Zhi Min, Liu Jianda, Wang Zichen, Zhang Ying, Pei Gendi, Li Linyuan, Mou Qi, Jia Jin

Coal Geology & Exploration

Fujian, located in the orogen region of the coastal areas of southeast China, exhibits well-developed structures and complex surface conditions, which make deep seismic reflection surveys challenging. In response to the diversity and complexity of seismogeological conditions in Fujian, this study optimized the seismic excitation means based on previous deep seismic surveys. Specifically, the combination of large, medium, and small guns was transitioned into the layout of normal guns (spacing of shot points: 600 m) and large shots (spacing of shot points: 15 km), leading to enhanced folds of large shots. Through simulation analysis, this study calculated the spacing of …


Mechanical Behavior And Failure Response Characteristics Of Hard Sandstones Considering Bedding Dip Angles, Song Zhanping, Liu Hongke, Zheng Fang, Cheng Yun, Sun Yinhao, Song Wanxue Dec 2023

Mechanical Behavior And Failure Response Characteristics Of Hard Sandstones Considering Bedding Dip Angles, Song Zhanping, Liu Hongke, Zheng Fang, Cheng Yun, Sun Yinhao, Song Wanxue

Coal Geology & Exploration

This study focuses on the mechanical behavior and failure responses of hard sandstones considering bedding dip angles. Through uniaxial compression tests of hard sandstones with different bedding dip angles, this study delved into the influence of bedding dip angles on the mechanical behavior of hard sandstones and the relationship between the bedding dip angles and fractal characteristics of hard sandstone fragments. The test results show that bedding dip angles produced negligible effects on the type of the stress-strain curves of hard sandstones. However, low dip angles (0°, 22.5°, and 45°) corresponded to unimodal curves, while high dip angles (67.5° and …


Coal-Based Solid Waste From The Panyi Mine In The Huainan Mining Area: Fine-Scale Chemical Structure And Ecological Risk Assessment Of Heavy Metals, Yin Wenwen, Zhang Liqun, Ding Dan, Shan Shifeng, Chen Yongchun, An Shikai, Zheng Liugen Dec 2023

Coal-Based Solid Waste From The Panyi Mine In The Huainan Mining Area: Fine-Scale Chemical Structure And Ecological Risk Assessment Of Heavy Metals, Yin Wenwen, Zhang Liqun, Ding Dan, Shan Shifeng, Chen Yongchun, An Shikai, Zheng Liugen

Coal Geology & Exploration

The utilization of clean coal-based solid waste is a pressing issue in the ecological construction of mining areas. To address this issue, the key is to ascertain the structures and morphology of heavy metals in coal-based solid waste. This study investigated the coal gangue and fly ash samples from the Panyi Mine in the Huainan mining area, Anhui Province. First, this study characterized the coal-based solid waste using microanalysis methods, such as X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Then, it examined the fine-scale chemical structure and heavy metal dissemination …


Current States , Prediction And Prevention Suggestions For Water Hazard Accidents In China’S Coal Mines, Sun Wenjie, Li Wenjie, Ning Dianyan, Ren Lingfeng Dec 2023

Current States , Prediction And Prevention Suggestions For Water Hazard Accidents In China’S Coal Mines, Sun Wenjie, Li Wenjie, Ning Dianyan, Ren Lingfeng

Coal Geology & Exploration

At present, the pattern of coal resource development in China has changed, but the water hazard accidents that restrict the safety production of coal mine still occur from time to time. In order to explore the characteristics and laws of water hazard accidents in coal mines in China and scientifically study and judge the evolution trend of water hazard accidents, study was performed in terms of the year, region, accident level and influencing factors of water hazard accidents, with the nationwide water hazard accidents from 2001 to 2022 as the statistical objects. Meanwhile, the Long Short-Term Memory (LSTM) model was …


Critical Links And Development Trends Of Research On Active Tectonics, Yuan Daoyang, Wang Youlin, Li Shuwu, Wang Wanhe, Li Linyuan, Zou Xiaobo, Wen Yameng Dec 2023

Critical Links And Development Trends Of Research On Active Tectonics, Yuan Daoyang, Wang Youlin, Li Shuwu, Wang Wanhe, Li Linyuan, Zou Xiaobo, Wen Yameng

Coal Geology & Exploration

Following a brief introduction of the general characteristics of active tectonics in China, this study analyzed two new features of large earthquakes with Ms ≥ 7 that have struck continental China since the beginning of the 21st century: (1) Large earthquakes occur primarily in clusters along the boundary fault zone of the Bayanhar active tectonic block—part of the Qinghai-Tibet ateau active tectonic block. (2) Reverse fault-fold earthquakes have occurred multiple times within active basins or at basin-mountain boundaries. In response to the new seismic activity features and the new demand for disaster prevention and mitigation of engineering construction and …


New Evidence For Holocene Activity Of The Northern Segment Of The Puqian-Qinglan Fault In Northern Hainan Province, Liu Huaguo, Li Feng, Jia Qichao, Wang Zhicheng, Zhang Pan, Lin Zhen, Zhang Jiehan, Shi Chunhua, Zhang Yanbo, Jia Wei, Li Changlong Dec 2023

New Evidence For Holocene Activity Of The Northern Segment Of The Puqian-Qinglan Fault In Northern Hainan Province, Liu Huaguo, Li Feng, Jia Qichao, Wang Zhicheng, Zhang Pan, Lin Zhen, Zhang Jiehan, Shi Chunhua, Zhang Yanbo, Jia Wei, Li Changlong

Coal Geology & Exploration

The Puqian-Qinglan fault, located in northern Hainan Province, is closely related to the judgment of the seismogenic structure of the Qiongshan M7½ earthquake in 1605. To accurately determine the latest activity characteristics of this fault, this study, adopting artificial shallow seismic exploration with large-tonnage seismic sources combined with small-spacing cross-well stratigraphic correlation, investigated the sedimentary geological conditions of the Quaternary basalt cover and significantly thick marine sand layers in northern Hainan Province through exploration at Qishantou and Dongzhai villages in the Sanjiang Town, Jiangdong New Area, Haikou. Key results are as follows: (1) the Puqian-Qinglan fault dislocates multiple marker …


Activity Variations Of The Shanzuokou-Sihong Fault Within The Jiangsu Segment Of The Tancheng-Lujiang Fault Zone And Their Origins, Zhang Hao, Li Wei, Li Limei, Yan Yunxiang, Jiang Xin, Wang Jinyan, Zhao Qiguang, Gu Qinping, Xu Hangang Dec 2023

Activity Variations Of The Shanzuokou-Sihong Fault Within The Jiangsu Segment Of The Tancheng-Lujiang Fault Zone And Their Origins, Zhang Hao, Li Wei, Li Limei, Yan Yunxiang, Jiang Xin, Wang Jinyan, Zhao Qiguang, Gu Qinping, Xu Hangang

Coal Geology & Exploration

The Shanzuokou-Sihong fault, having undergone the entire evolutionary process of the Tancheng-Lujiang fault zone, exhibits segmentation during the latest activity epoch. Determining the location and origin of its activity segmentation will provide a significant reference for exploring the activity variations of its branch faults and their origins. This study investigated the activity of the Shanzuokou-Sihong fault using a three-dimensional approach combining field geological surveys, shallow seismic exploration, and cross-well stratigraphic correlation. The results show that the Shanzuokou-Sihong fault is a Late Pleistocene active fault on the east side of the North Maling Mountain and a Middle Pleistocene fault in Xinyi …


Activity Of The Liyang-Nandu Fault In Southern Jiangsu, Zhang Shuo, Zhang Ping, Chen Huogen, Xu Shugang, Gong Xulong, Xu Hangang, Li Limei, Feng Wenli, He Zongnan Dec 2023

Activity Of The Liyang-Nandu Fault In Southern Jiangsu, Zhang Shuo, Zhang Ping, Chen Huogen, Xu Shugang, Gong Xulong, Xu Hangang, Li Limei, Feng Wenli, He Zongnan

Coal Geology & Exploration

Located in the central part of the Sunan Modernization Construction Demonstration Area—one of the areas with the densest population and urban areas and the most developed economy in China, the Liyang-Nandu fault is an important concealed fault with a nearly E-W strike in the Yangtze River Delta in eastern China. This fault serves as an important regional geomorphic and neotectonic boundary. However, there is a lack of systematic research on this fault, and its latest activity era is yet to be ascertained. Using seismic exploration P-waves and S-waves and cross-well stratigraphic correlation, this study investigated the spatial distribution and Quaternary …


Theory And Application Of Setback Distance From Active Faults, Wei Leiming, Xu Xiwei, Li Feng, Cao Jun, Ren Junjie, Cheng Jia, Zhang Xianbing, Jia Qichao, Chen Guihua, Wu Xiyan Dec 2023

Theory And Application Of Setback Distance From Active Faults, Wei Leiming, Xu Xiwei, Li Feng, Cao Jun, Ren Junjie, Cheng Jia, Zhang Xianbing, Jia Qichao, Chen Guihua, Wu Xiyan

Coal Geology & Exploration

Determining setbacks from active faults is the “last 1 km” from active fault surveys to their application to seismic disaster mitigation. It is also a technique for blocking the risk sources of earthquake-induced chains of geologic hazards. Field investigations and experimental studies have demonstrated that buildings and structures can be free from catastrophic destruction caused by coseismic ruptures and offset of active faults provided they are kept at a certain finite distance from the active fault traces. Therefore, determining setbacks from active faults serves as an ultimate goal of the surveys and precise localization of active faults. Based on the …


Revealing Fine-Scale Crustal Structure And Tectonic Features In The Xiong’An New Area And Its Periphery Using Deep Seismic Reflection Profiling, Yue Hangyu, Wang Kai, Wang Xiaojiang, Zhang Baowei, Zhang Kai Dec 2023

Revealing Fine-Scale Crustal Structure And Tectonic Features In The Xiong’An New Area And Its Periphery Using Deep Seismic Reflection Profiling, Yue Hangyu, Wang Kai, Wang Xiaojiang, Zhang Baowei, Zhang Kai

Coal Geology & Exploration

As an effective method to accurately reveal the deep geological structures and tectonic features of the Earth, deep seismic reflection profiling has been increasingly applied to the exploration of the continental and oceanic crusts, as well as the upper mantle of the lithosphere, making it internationally recognized pioneer technique for deep Earth exploration. This study examined the deep seismic reflection profile spanning across the Xiong’an New Area in Hebei Province, aiming to reveal the crustal structure and tectonic features of the study area. Key findings are as follows: (1) The crust in the study area can be divided into the …


Revealing The Upper Crustal Structure In The Fujian Region Using Deep Seismic Profiling, Li Pei, Ren Congrong, Li Haiyan, Wang Shanxiong Dec 2023

Revealing The Upper Crustal Structure In The Fujian Region Using Deep Seismic Profiling, Li Pei, Ren Congrong, Li Haiyan, Wang Shanxiong

Coal Geology & Exploration

The Fujian region, located along the southeastern margin of the Chinese continent, constitutes an active tectonic belt along the coastal area in southeast China, with complex formation and evolution histories. To understand the characteristics of upper crustal structures and basement structures in the Fujian, this study collected the Pg travel time data from four NE-trending deep seismic sounding (DSS) survey lines in the region. Employing finite-difference tomography, this study obtained the fine-scale velocity structure of the upper crust along the four profiles, revealing the lateral variations in the upper crustal velocity structure, basement structures, and shallow fault characteristics in the …


Analogue Modeling Of Love-Type Channel Waves And Their Response To Faults, Liu Qiang, Hu Jiwu, Wang Pan, Shi Xianxin, Jia Qian Dec 2023

Analogue Modeling Of Love-Type Channel Waves And Their Response To Faults, Liu Qiang, Hu Jiwu, Wang Pan, Shi Xianxin, Jia Qian

Coal Geology & Exploration

Owing to its high resolution and low energy attenuation, channel wave-based seismic exploration has been widely applied in the geophysical prospecting of hidden disaster-causing factors in underground coal mines. However, its accuracy fails to meet the requirements of intelligent mine mining presently. At present, the analogue modeling of channel waves mostly focuses on Rayleigh-type channel waves using 2D models, leading to a lack of research on Love-type channel waves. To explore the propagation law of Love-type channel waves, this study investigated the waves in the 3D analogue modeling of channel waves. Firstly, the wave and particle vibration characteristics of Love-type …


Multipoint Sources-Based High-Resolution Electrical Detection Of The Water-Rich Areas Near Mining Faces Of Coal Mine Roadways, Wu Rongxin, Xu Hui Dec 2023

Multipoint Sources-Based High-Resolution Electrical Detection Of The Water-Rich Areas Near Mining Faces Of Coal Mine Roadways, Wu Rongxin, Xu Hui

Coal Geology & Exploration

To accurately explore the spatial distribution of water-rich areas near mining faces of mine roadways, this study proposed a multipoint sources-based high-resolution electrical detection technology. A multi-channel electrode observation system was arranged behind a roadway mining face, with electrodes at a distance of 1/4 measuring lines behind the mining face as point source electrodes sequentially. Data were collected using a monopole-dipole device, with the obtained apparent resistivity considered the sounding data of multipoint sources-based electrical detection. The images of multipoint sources-based electrical sounding allow for quickly determining the presence of water-rich areas and their locations relative to the mining faces …


Obstacle-Avoidance Trajectory Planning Of Mine Drilling Robot During Drill Pipe Loading And Unloading, Yao Yafeng, Yao Ningping, Peng Tao, Liang Chunmiao, Peng Guangyu Nov 2023

Obstacle-Avoidance Trajectory Planning Of Mine Drilling Robot During Drill Pipe Loading And Unloading, Yao Yafeng, Yao Ningping, Peng Tao, Liang Chunmiao, Peng Guangyu

Coal Geology & Exploration

The position of drill pipe loading and unloading by mine drilling robot will change with the attitude adjustment of the host machine, and obstacles are present in the loading and unloading path of drill pipe. Therefore, there is a problem of obstacle-avoidance trajectory planning with variable targets in the loading and unloading of drill pipe. For this reason, the DH parameter table was created according to the performance parameters of the explosion-proof 6-DOF manipulator, and the function relation of the change in loading and unloading position of drill pipe before and after the attitude adjustment of the 3-DOF host machine …


Stress Field Of High-Temperature Wellbore Under Spray Cooling For Underground Coal Gasification, Tang Yang, Xie Na, Xiong Haoyu, He Yin, Huang Shunxiao Nov 2023

Stress Field Of High-Temperature Wellbore Under Spray Cooling For Underground Coal Gasification, Tang Yang, Xie Na, Xiong Haoyu, He Yin, Huang Shunxiao

Coal Geology & Exploration

As a supplement to traditional physical coal mining technology, underground coal gasification (UCG) is a new generation of chemical coal mining technology. During the gasification, the wellbore of UCG production wells is subjected to the combined action of high temperature and internal pressure loads. Targeting the structural characteristics of the wellbore of UCG production wells, this study, based on the heat transfer theory, established a calculation model for the transient temperature of the wellbore under the cooling through annular spray water injection. By combining the wellbore pressure model, as well as the elasticity theory and the wall cylinder theory, this …


Table Of Contents, The Editors Nov 2023

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Numerical Simulations Of The Effects Of Bedding Planes On Hydraulic Fracture Propagation Law In Oil Shale, Li Yanwei, Zhu Chaofan, Zeng Yijian, Shui Haoche, Fan Cunhan, Guo Wei Nov 2023

Numerical Simulations Of The Effects Of Bedding Planes On Hydraulic Fracture Propagation Law In Oil Shale, Li Yanwei, Zhu Chaofan, Zeng Yijian, Shui Haoche, Fan Cunhan, Guo Wei

Coal Geology & Exploration

Hydraulic fracturing serves as a major technical means for the exploitation of oil shale reservoirs presently, and the hydraulic fracture morphology in oil shales is primarily affected by differences in the characteristics of bedding planes. However, current studies mostly focus on the influence of the developmental degree of bedding planes on fracture propagation, overlooking the effects of the bedding plane thickness itself on hydraulic fracture propagation. This study delves into the oil shale in the Xunyi area, Ordos Basin. Based on the theory of linear elastic fracture mechanics, this study developed a stress-damage-seepage model of hydraulic fracture propagation. Using the …


Vertical Variability Of Hydrogeological Characteristics Of Luohe Formation By Double Packer System Pumping Test, Li Chaofeng, Liu Yexian, Zhang Jinkui, Ren Dengjun, Hou Tao, Liu Zengping, Xu Xinqi, Ma Ji, Wang Qingzhen, Duan Xiliang, Xing Jiebo, Li Yang Nov 2023

Vertical Variability Of Hydrogeological Characteristics Of Luohe Formation By Double Packer System Pumping Test, Li Chaofeng, Liu Yexian, Zhang Jinkui, Ren Dengjun, Hou Tao, Liu Zengping, Xu Xinqi, Ma Ji, Wang Qingzhen, Duan Xiliang, Xing Jiebo, Li Yang

Coal Geology & Exploration

To investigate the hydrogeological conditions of the thick Luohe Formation in Ordos Basin and quantitatively evaluate vertical variation characteristics of its aquifer’ s water-rich, proposes the method of using the coefficient of transmissibility to evaluate the water-rich of the aquifer, and give the seven level classification standard of water-rich by the method of determining coefficient of transmissibility. The double-packer system was used to carry out the pumping tests of 10 vertical sections of fixed thickness of the Luohe Formation in the DJ1 and DJ2 boreholes in the Gaojiabao mine field, shaanxi, and the hydrogeological parameters were calculated. Using the comprehensive …


Characteristics And Genetic Mechanism Of Low Sulfate In High-Salt Groundwater Of Permian Sandstone In Fudong Mining Area, Huainan, Jiang Chunlu, Huang Wendi, Fu Xianjie, Zheng Liugen, Cheng Shigui, Shan Chonglei Nov 2023

Characteristics And Genetic Mechanism Of Low Sulfate In High-Salt Groundwater Of Permian Sandstone In Fudong Mining Area, Huainan, Jiang Chunlu, Huang Wendi, Fu Xianjie, Zheng Liugen, Cheng Shigui, Shan Chonglei

Coal Geology & Exploration

Hydrogeochemistry research of groundwater in coal mining areas is of great significance to the prevention and control of mine water and the comprehensive utilization of water resources. In terms of the low surfate of Permian sandstone water in Fudong mining area, Anhui Huainan Coalfield, the hydrochemical characteristics, water-rock interaction and low sulfate genesis of sandstone water were studied through water sampling and test by multivariate statistical method, in combination with the hydrogeological condition analysis and the sulfur and oxygen isotope technology. The results show that the Permian sandstone water in the study area is weakly alkaline, with an average TDS …


Evaluation Of Water Quality And Identification Of Pollution Factors In Mining Subsidence Area With High Phreatic Water Level, Hu Lin, Chen Yongchun, Xu Yanfei, Li Bing, Wang Jin, An Shikai, Chen Chen, Sun Hongjie, Miao Wei Nov 2023

Evaluation Of Water Quality And Identification Of Pollution Factors In Mining Subsidence Area With High Phreatic Water Level, Hu Lin, Chen Yongchun, Xu Yanfei, Li Bing, Wang Jin, An Shikai, Chen Chen, Sun Hongjie, Miao Wei

Coal Geology & Exploration

Huainan mining area is characterized by a high phreatic water level, as well as a wide range and large area of coal mining subsidence areas, with the water quality monitoring data missing and prominent water environment. Therefore, the evaluation of water quality monitoring and identification of pollution factors in large subsidence area is of great significance to regional water environmental governance. Specifically, the water quality of the subsidence area was evaluated with the Nemerow pollution index method by testing the water samples collected from 175 sampling points in the study area. Meanwhile, the eutrophication state of water bodies was evaluated …


Rate-Of-Penetration (Rop) Prediction Model Based On Formation Characteristics Of Extremely Thick Plastic Mudstone In South China Sea, Zeng Xiaolong, Li Qian, Wei Hongchao, Chen Jiahao, Zhu Haiyan Nov 2023

Rate-Of-Penetration (Rop) Prediction Model Based On Formation Characteristics Of Extremely Thick Plastic Mudstone In South China Sea, Zeng Xiaolong, Li Qian, Wei Hongchao, Chen Jiahao, Zhu Haiyan

Coal Geology & Exploration

In terms of petroleum and gas resources, South China Sea is the important energy replacement area in China. However, most of the reservoirs are buried deep, and the strong plasticity of the formation under high confining pressure and the complex geological environment seriously affect the drilling efficiency. It is also very difficult to accurately predict the ROP. Hence, a set of intelligent ROP prediction model was established for the extremely thick mudstone formation with unique viscoelastic and strong plastic characteristics in South China Sea. The model took the actual data of 10 wells in an area of South China Sea …


Numerical Simulations Of Enhancing Permeability And Gas Extraction Of Thick Coal Seams Through Static Fracturing, Wang Xinfeng, Liu Wengang, Wang Long, Wei Youyu, Zhang Qiao Nov 2023

Numerical Simulations Of Enhancing Permeability And Gas Extraction Of Thick Coal Seams Through Static Fracturing, Wang Xinfeng, Liu Wengang, Wang Long, Wei Youyu, Zhang Qiao

Coal Geology & Exploration

This study seeks to improve the underground operation efficiency and optimize the borehole arrangement parameters for static fracturing of coal seams. To this end, this study conducted tests in the belt roadway of the No. 12316 fully mechanized mining face in the Wangjialing Coal Mine, China Coal Huajin Group. By combining the equations for coal seams’ deformation and failure, gas diffusion and seepage, and coal seams’ permeability evolution, this study constructed a model of the damage and permeability evolution of coal seams. Based on the numerical simulations of the process of static fracturing and permeability enhancement of coals, as well …


Genetic Type And Gas-Generating Potential Of Coalbed Methane In The Bayanhua Sag, Erlian Basin, Meng Qin, Li Ling, Li Jie, Tian Wenguang, Lin Haitao, Li Heng Nov 2023

Genetic Type And Gas-Generating Potential Of Coalbed Methane In The Bayanhua Sag, Erlian Basin, Meng Qin, Li Ling, Li Jie, Tian Wenguang, Lin Haitao, Li Heng

Coal Geology & Exploration

The Bayanhua Sag in the Erlian Basin is a critical experimental area for coalbed methane (CBM) development from low-rank coals in Inner Mongolia. However, the relatively low exploration level and the limited understanding of the CBM origin in the sag restrict the CBM exploration and development to some extent. This study tested the gas components, stable isotopes and hydrochemistry of the gas and water samples from CBM wells in the Bayanhua Sag. It also conducted radioisotopic dating for these samples. By combining the classic charts for the identification of natural gas origin, this study clarified the gas origins, further analyzed …


A Simulation Study On The Suspension And Transport Patterns Of Proppants In Long Distance Pipelines For Integrated Well And Ground Fracturing, Li Haozhe, Jiang Zaibing, Sun Siqing, Zhu Chuanyong, Fan Yao, Guo Yong, Cheng Bin Nov 2023

A Simulation Study On The Suspension And Transport Patterns Of Proppants In Long Distance Pipelines For Integrated Well And Ground Fracturing, Li Haozhe, Jiang Zaibing, Sun Siqing, Zhu Chuanyong, Fan Yao, Guo Yong, Cheng Bin

Coal Geology & Exploration

Integrated well and ground fracturing is a developmental trend for the staged fracturing of underground long boreholes in coal mines. Using the integrated fracturing technology, the fracturing fluids, after being pressurized using a ground fracturing pump, enter long boreholes in underground coal mines through ground penetrating wells and long distance pipelines, aiming to achieve fracturing with high injection rates of fracturing fluids. The suspension and transport patterns of proppants in long distance pipelines hold critical significance for optimizing parameters related to proppant adding and avoiding sand plugging in pipelines. This study evaluated the rheological properties and proppant carrying capacity of …


Dynamic Prediction Method Of Tunnel Water Inflow Based On Detailed Depiction Of Complex Geological Bodies, Du Yajun, Li Qingbo, Wan Weifeng, Yang Fengwei, Li Yazhe, Qian Hui Nov 2023

Dynamic Prediction Method Of Tunnel Water Inflow Based On Detailed Depiction Of Complex Geological Bodies, Du Yajun, Li Qingbo, Wan Weifeng, Yang Fengwei, Li Yazhe, Qian Hui

Coal Geology & Exploration

It is a challenge to accurately characterize the irregular geological bodies and underground structures such as inclined faults and inclined tunnels during the numerical simulation of tunnel water inflow prediction, and the prediction generally assumes that the tunnel excavation is completed instantaneously without considering the construction progress. A dynamic prediction method for tunnel water inflow based on precise characterization of complex geometric bodies was proposed by addressing the non-self-intersection and watertight issues required in the coupling process of three-dimensional (3D) geological models and 3D groundwater numerical models. Specifically, a sealed boundary interface of inclined tunnels, shafts, inclined faults and irregular …


A Method For Evaluating Aquiclude Stability In The Water Conservation-Based Mining Of Shallowly Buried Coal Seams In Ecologically Vulnerable Areas In Northwest China, Li Heng, He Tao, Guo Bin Nov 2023

A Method For Evaluating Aquiclude Stability In The Water Conservation-Based Mining Of Shallowly Buried Coal Seams In Ecologically Vulnerable Areas In Northwest China, Li Heng, He Tao, Guo Bin

Coal Geology & Exploration

Water conservation and coal mining are both critical to Northwest China. Water conservation-based coal mining is an important technology for the coordinated development of coal and water resources in this region. In this technology, the evaluation of aquiclude stability is critical. Due to the shallow depth of coal seams, intense topographic cutting, and complex changes in near-surface aquifers in the ecologically vulnerable areas in Northwest China, there exist large errors between traditional methods for aquiclude evaluation and the actual hydrological observations in these areas. To address this challenge, this study develops using the 3D geological modelling combined with numerical simulation …


Micp Restoration Law Of Coal Mining Induced Ground Fissures And Its Influencing Factors, Li Tao, Gao Ying, Yan Jingwang, Zhang Jiarui, Kou Guigui, Ma Tengfei, Mei Aoran Nov 2023

Micp Restoration Law Of Coal Mining Induced Ground Fissures And Its Influencing Factors, Li Tao, Gao Ying, Yan Jingwang, Zhang Jiarui, Kou Guigui, Ma Tengfei, Mei Aoran

Coal Geology & Exploration

The coal mining induced ground fissures in the loess covered area of northwest China cause shallow groundwater resource leakage and soil instability. Therefore, the experimental study was conducted on Microbial Induced Carbonate Precipitation (MICP) restoration of coal mining induced ground fissures in the loess covered area. Specifically, the characteristics of mining induced ground fissures were observed and their development characteristics were revealed based on Ningtiaota Coal Mine in northern Shaanxi. The coal mining induced ground fissures in loess were classified with consideration to the observed mine pressure. Based on the classification and characteristics of coal mining induced ground fractures, the …


Experimental Study On Proportioning Of Ultra-High Strength Similar Materials For Large Similarity Ratio Model Tests, Zhan Xinyu, Gao Lin, Zhao Fanghao, Wang Yongyin, Liu Ping, Han Sen Nov 2023

Experimental Study On Proportioning Of Ultra-High Strength Similar Materials For Large Similarity Ratio Model Tests, Zhan Xinyu, Gao Lin, Zhao Fanghao, Wang Yongyin, Liu Ping, Han Sen

Coal Geology & Exploration

Similar simulation of physical material is a common research method in the field of geotechnical engineering. Selecting appropriate similar materials and determining their proportions is the key to successfully simulating the prototype project. Existing similar materials are mostly developed for similar simulation with small geometric similarity ratio (1∶250-1∶25). These materials generally have low strength (0.2-7.6 MPa), making it difficult to meet the requirements of large similarity ratio model. Therefore, in order to prepare an ultra-high strength similar material with a strength of more than 10 MPa suitable for large similarity ratio model, river sand, barite, gypsum, and cement with different …


Mechanical Properties And Strength Deterioration Mechanism Of Soil In Inner Dump Of Open-Pit Coal Mine Under The Action Of Freeze-Thaw Cycles, Zhang Heyong, Wang Xuedong, Zhu Yongdong, Wang Haipeng, Qi Lihui Nov 2023

Mechanical Properties And Strength Deterioration Mechanism Of Soil In Inner Dump Of Open-Pit Coal Mine Under The Action Of Freeze-Thaw Cycles, Zhang Heyong, Wang Xuedong, Zhu Yongdong, Wang Haipeng, Qi Lihui

Coal Geology & Exploration

In order to investigate the influence mechanism of freeze-thaw cycles on the structure and mechanical properties of soil, the typical clay soil in the inner dump of Yuanbaoshan open-pit coal mine in Inner Mongolia was taken as the research object, and the simulation analysis of the internal temperature, moisture and stress fields of the soil was carried out through laboratory freeze-thaw cycle tests and MatDEM numerical simulation. The results show that: freeze-shrinkage occurs to the soil in the dump after the freeze-thaw cycles, and the stress-strain curve shows the trend of strain softening at low confining pressure for shear failure, …