Damaged Constitutive Model Of Frozen Sand Under The Influence Of Intermediate Principal Stress,
2020
State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, Anhui University of Science and Technology, Huainan 232001, China; School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232002, China
Damaged Constitutive Model Of Frozen Sand Under The Influence Of Intermediate Principal Stress, Ma Shilong, Yao Zhaoming, Liu Shuang, Pan Xuan
Coal Geology & Exploration
Artificial freezing is a commonly used method for stopping water and providing temporary support during the excavation of saturated sand. This study on the damage characteristics of frozen soil lays the foundation for the analysis of the mechanical properties of frozen soil and the stability of frozen bodies. In order to study the damage mechanical properties of frozen sand, three-dimensional laboratory tests on frozen sand with different intermediate principal stress coefficients were carried out at -5℃. Based on the Weibull random distribution of micro element failure of frozen soil, the Drucker-Prager strength criterion was invoked as the statistical distribution variable, …
Model Of Surface Subsidence Basin For Long-Wall Working Face Along Strike Of Gently Inclined Coal Seam,
2020
College of Geology & Environment, Xi’an University of Science and Technology, Xi’an 710055, China
Model Of Surface Subsidence Basin For Long-Wall Working Face Along Strike Of Gently Inclined Coal Seam, Tang Yichuan, Xing Congcong, Liu Donghai, Deng Niandong, Yao Ting, Shang Hui
Coal Geology & Exploration
In order to accurately describe the distribution of surface subsidence basin, and based on the power exponential function model and the subsidence features, the surface subsidence basin model of long-wall working face along strike with gently inclined coal seam was established concerned the combination of theoretical analysis and numerical simulation method. The influencing factors of model parameters and the changing patterns of parameters were analyzed, and the applicability and the predicting accuracy of the model were verified. The results showed that parameter n reflected the range of the bottom size of the sinking basin, which was mainly related to the …
Numerical Simulation Of Coaxial Heat Transfer Capacity Of Deep Vertical Wells,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China; Shaanxi Key Laboratory of Coal Mine Water Hazard Prevention and Control Technology, Xi'an 710078, China
Numerical Simulation Of Coaxial Heat Transfer Capacity Of Deep Vertical Wells, Zhao Chunhu, Shang Hongbo, Jin Dewu, Wang Hao, Xu Shuanhai, Wang Xiaodong, Zhang Weidong
Coal Geology & Exploration
Aiming at the scientific evaluation of coaxial casing heat transfer of geothermal resources with medium burial depth(1 500-4 000 m), a rock-water coupled heat transfer model of a vertical single well was built based on the simulation platform of COMSOL Multiphysics software. Taking the stratigraphic and geothermal characteristics of Xi'an area as the simulation background, the heat transfer capacity of single well(3 500 m)casing under two different geothermal gradients(0.027℃/m and 0.030℃/m) and four flow velocities(0.25, 0.50, 0.75, 1.00 m/s) was calculated and analyzed. Meanwhile, the numerical models of group wells with five kinds of well spacing were established, and the …
Sedimentary Response To The Uplift Of The Liupan Shan Since The Late Pleistocene And Its Environmental Effects,
2020
Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China; Key Laboratory of Paleomagnetism and Tectonic Reconstruction of Ministry of Natural Resources, Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100082, China
Sedimentary Response To The Uplift Of The Liupan Shan Since The Late Pleistocene And Its Environmental Effects, Ma Zhaoying, Dong Xiaopeng, Zhang Qing, Cui Jiawei
Coal Geology & Exploration
Liupan Shan lies between the Tibetan plateau and Ordos block and has been under the remote effect of the northeastward extension of the Tibetan plateau. The former research about the uplift of Liupan Shan mainly focused on the petrology, structural deformation or tectonic evolution study from the Cretaceous to early period of Cenozoic. However, the Late Pleistocene geological study closely connected with the human activities was rarely mentioned. In this study, we carried out systematic sedimentary research in the Qingshuihe basin adjacent to the Liupan Shan tectonic belt, re-determine the sedimentary sequence at first, then reverse the uplift history of …
Application Of The Dip Curvature Attributes In The Recognition Of Coal Roadway,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Application Of The Dip Curvature Attributes In The Recognition Of Coal Roadway, Shan Rui
Coal Geology & Exploration
The intelligent accurate coal mining needs to construct the high-precision and transparent 3D geological model, and the seismic data interpretation integrated into the dynamic roadway data provide data support for the model. The geological model of roadway is established and forward modeling is carried out to analyze the difference of seismic characteristics caused by a roadway. Based on curvature attribute principle, various seismic curvature attributes were applied to seismic data interpretation, guide the roadway recognition in the seismic data. The coal seam 2 of CJT coalfield was selected as the research object, and the high-quality seismic data and various attribute …
Velocity Analysis Method Of Reflected In-Seam Wave Detection Technique,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Velocity Analysis Method Of Reflected In-Seam Wave Detection Technique, Yang Yanjun, Zhu Shujie, Zhang Xiaowen, Wang Ji
Coal Geology & Exploration
During the excavation of the roadway, using reflected in-seam waves detection technique to explore the structure of roadway and accurately interpret the wave impedance interface is of signality for mine production. The method of detecting the position of faults by reflected in-seam waves is usually inaccurate, which is mainly caused by the selected deviation of reflected in-seam waves velocity. In order to reduce the selected deviation of reflected in-seam waves velocity, this paper analyzed the features of reflected in-seam waves velocity of fifteen coal seam in thirteen coal mines and the velocity relationships of reflected in-seam waves, direct in-seam waves …
Review Of The Tight Radius Drilling Technology Based On High Pressure Water Jet,
2020
China Coal Research Institute, Beijing 100013, China; Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Review Of The Tight Radius Drilling Technology Based On High Pressure Water Jet, Fan Yao, Zhang Qun
Coal Geology & Exploration
Tight radius drilling technology based on high pressure water jet is an important technical means to realize low-cost and efficient development of oil and gas resources. According to the research and application of tight radius drilling technology based on high pressure water jet, the equipment buildup, drilling theory, technical process and application effect of three tight radius drilling technologies and equipments(i.e., forging milling and reaming hydraulic type, forging milling and reaming jet thrust type and casing window type) are summarized systematically, and the advantages, disadvantages and adaptability of different technologies are included. From the point of view of increasing production …
Simulation Of The Cutter Arrangement Pattern Of The Arc Pdc Drill Bit,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Simulation Of The Cutter Arrangement Pattern Of The Arc Pdc Drill Bit, Ju Pei, Wang Chuanliu
Coal Geology & Exploration
When drilling in a complex heterogeneous formation, due to the limitation of bit crown shape, the cutters of each part of the bit are subjected to non-uniform force, and the cutters at the local location are subjected to large impact load, which lead to the occurrence of bit vortex. In order to solve the problem, a “multi-level force balance” cutter circumferential arrangement scheme is proposed. By establishing the rock breaking finite element simulation model of the bit, the mechanical characteristics of the cutter and the bit under three circumferential cutter distribution modes(clockwise, counterclockwise and “multi-level force balance”) are analyzed. Simulation …
Table Of Contents,
2020
China Coal Technology and Engineering Group (CCTEG)
Geological Modeling-Based Productivity Response Characteristics Of The Cbm Well In Baode Unitⅰ,
2020
School of Energy Resource, China University of Geosciences(Beijing), Beijing 100083, China; Coal Reservoir Laboratory of National Engineering Research Center of CBM Development & Utilization, China University of Geosciences(Beijing), Beijing 100083, China
Geological Modeling-Based Productivity Response Characteristics Of The Cbm Well In Baode Unitⅰ, Chen Bo, Tang Dazhen, Lin Wenji, Li Song, Zhong Guanghao, Zhu Xueguang
Coal Geology & Exploration
Coalbed methane resource conditions and reservoir physical conditions are the basis of CBM exploration and exploitation. The geological modeling of CBM reservoir was carried out to clarify the spatial distribution of coal reservoir, and explain the difference of single well productivity, which can provide theoretical basis for selection and well drilling. This paper took Baode unit I as research object. Based on the measured data of gas content and well test permeability, the inversion model of gas content and permeability in the study area was established by using support vector machine algorithm(SVM) and transformed F-S permeability calculation formula, and the …
Quantitative Evaluation Of The Contamination Degree Of The Drilling Fluid For Fractures Of Different Scale In Coal,
2020
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454003, China
Quantitative Evaluation Of The Contamination Degree Of The Drilling Fluid For Fractures Of Different Scale In Coal, Zhang Jingshuo, Ni Xiaoming, Li Yang, Li Zongyuan, Cao Yunxing
Coal Geology & Exploration
During coalbed methane well drilling, the drilling fluid contaminates and blocks the pores and fractures of coal seam. In order to find out the difference of pollution degree of drilling fluid coal and the contribution rate of the pores and fractures of different scale to permeability, the coal of Changping mine was taken as the research object, the scanning electron microscopy(SEM) and the Image Pro Plus(IPP) processing technology were used, the parameters such as the average length, the average width, the total area and the total perimeter of the fractures of different scales in coal before and after contamination were …
Discussion On The Three-Dimensional Development Model Of The Old Well Pattern In Coalbed Methane Field,
2020
Huabei Oilfield Shanxi CBM Branch Company of Huabei Oilfield Company PetroChina, Changzhi 046000, China
Discussion On The Three-Dimensional Development Model Of The Old Well Pattern In Coalbed Methane Field, Li Jun, Zhang Cong, Zhang Jianguo, Peng He, Cui Xinrui, Zhu Min
Coal Geology & Exploration
In order to increase the degree of production of CBM development blocks, when the production of a single well enters a decline period, the development plan needs to be adjusted, and the production increase and stability can be achieved through the measures such as layer adjustment or layer compensation. In terms of time, it is believed that the main coal seam should be developed first when it is put into production. After the decline period, the secondary main coal seam should be supplemented and combined; in space, combined with the development dynamics, the analytic hierarchy process is used to determine …
The Pca-Logistic Method For Identification Of Water Burst In Nalinhe No.2 Coal Mine,
2020
China Coal Energy Research Institute Co., Ltd., Xi'an 710054, China; China Coal Rock Burst and Water Hazard Control Center, Ordos 017200, China
The Pca-Logistic Method For Identification Of Water Burst In Nalinhe No.2 Coal Mine, Ji Zhuochen, Ding Xiang, Hou Enke, Pu Zhiguo, Xie Peng
Coal Geology & Exploration
Nalinhe No.2 coal mine is the first pair of large-scale mines in the Nalinhe mining area. The water inrush events occur from time to time due to its own complex hydrogeological conditions and strong disturbance of excavation in the initial stage of production, which has caused serious threat to the mining activity safety. Finding the source of gushing water quickly and effectively is the key to control the mine water disaster. Based on the water quality analysis of main aquifers and goaf water samples in Nalinhe No.2 coal mine, and drawing the piper trilinear nomograph water samples, the hydrogeochemical characteristics …
Method And Practice Of Quality Test After Grouting In Coal Mine Goaf,
2020
Institute of Geotechnical Engineering, Xi'an University of Technology, Xi'an 710048, China ; Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China
Method And Practice Of Quality Test After Grouting In Coal Mine Goaf, Liu Xiaoping, Li Shan, Liu Xinxing, Cao Xiaoyi, Wang Yutao
Coal Geology & Exploration
Grouting quality test is the key technology for efficient development and utilization of waste land in the goaf of a coal mine, it is of great significance to evaluate the stability of the site and the safety of construction after goaf management. Based on many engineering practices, this paper summarizes the evaluation method of the qualified standards of the grouting quality and the errors existed in the testing work. The results proved that the quality inspection after grouting is a systematic work. The test method could be optimized according to the characteristics of the construction and grouting design requirements, following …
Numerical Experiment On Damage And Fracture Of Shale Based On Micro-Scale,
2020
College of Civil Engineering, Guizhou University, Guiyang 550026, China
Numerical Experiment On Damage And Fracture Of Shale Based On Micro-Scale, Cui Hengtao, Wu Zhonghu, Lou Yili, Zuo Yujun, Sun Wenjibin, Liu Hao
Coal Geology & Exploration
Correctly understanding the micro-scale fracture characteristics of the Lower Cambrian shale and the evolution law of acoustic emission signals are of great reference value in the study of shale mechanical characteristics, fracture mechanism and shale gas development and utilization. In this paper, based on digital image processing technology, the non-uniform characterization of quartz-filled shale is carried out, and a numerical model is established using the real rock fracture analysis system RFPA2D-DIP to simulate the failure process of shale under different confining pressures. The test results show that under the micro-scale structure, the shale failure mode can be roughly …
Characteristics Of In-Situ Stress Field And Stability Analysis Of Roadway In Hongqingliang Coal Mine,
2020
College of Mining, Liaoning Technical University, Fuxin 123001, China
Characteristics Of In-Situ Stress Field And Stability Analysis Of Roadway In Hongqingliang Coal Mine, Rong Hai, Han Yongliang, Zhang Hongwei, Xin Jinxin, Cao Yu, Lan Tianwei
Coal Geology & Exploration
The in-situ stress of 3-1 coal seam in Hongqingliang coal mine was measured by hollow core inclusion measurement, and distribution characteristics of in-situ stress field were obtained in order to solve the problem of serious deformation in mining roadway. Fault structures of grade Ⅰ-Ⅴ in Hongqingliang coal mine were divided by geo-dynamic division method, and the stress areas were divided and the stability of roadways was analysis by rock stress state analysis system. The research showed that the in-situ stress field in Hongqingliang coal mine belongs to the horizontal tectonic stress field, which is dominated by horizontal compressive stress. The …
Effect Of Thermally Conductive Filler On Thermal Conductivity Of Cementing Materials In Geothermal Wells,
2020
China Coal Research Institute, Beijing 100013, China; Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710078, China
Effect Of Thermally Conductive Filler On Thermal Conductivity Of Cementing Materials In Geothermal Wells, Yang Yu, Xu Shuanhai, Zhang Hao, Han Yongliang, Zhang Weidong
Coal Geology & Exploration
Adding heat-conducting filler to the cement of the geothermal well could significantly improve the thermal conductivity of the cement stone and enhance the heat extraction effect of the geothermal well. In this study, on the basis of summarizing the heat conduction path theory and concept of high packing density, the effects of different filler types, particle sizes and dosages on the thermal conductivity of cementing cement were investigated through experiments. The test results showed that graphite had the best effect on improving the thermal conductivity of cement stone compared to other types of filler; the larger the graphite particle size, …
Multi Parameter Monitoring System And Device For Mine Gas Drainage,
2020
Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China
Multi Parameter Monitoring System And Device For Mine Gas Drainage, Dai Chenyu
Coal Geology & Exploration
In order to make up for the deficiency of the regional monitoring of the traditional gas drainage monitoring system, this paper proposes to build a borehole gas drainage monitoring system with borehole as the monitoring unit, which can dynamically grasp the drainage effect of each borehole in the process of gas drainage in real time, change the large area regional measurement into the measurement of each borehole in the region, and realize the fine monitoring of gas drainage. According to the requirements of borehole gas drainage monitoring system, combined with the characteristics of gas drainage parameters at the borehole orifice, …
Microseismic Vector Scanning-Based Natural Fracture Monitoring Of The Coalbed Methane Wells,
2020
COSL Oilfield Production Research Institute, Tianjin 300460, China
Microseismic Vector Scanning-Based Natural Fracture Monitoring Of The Coalbed Methane Wells, Liu Zixiong
Coal Geology & Exploration
The development degree of natural fractures is the main factor affecting coalbed methane productivity. In order to accurately obtain the distribution position of the natural fractures in the a coalbed methane field in the southern Qinshui basin, 7 refracturing wells in the area were adopted by surface microseismic vector scanning to monitor the natural fractures. A certain amount of three-component geophones were deployed around the fracturing well to collect microseismic events in the surrounding reservoir during fracturing, and after Semblance superposition, the fracture energy slices at different times in the monitoring area were obtained to explain the natural fractures in …
Study On Time-Frequency Characteristics And Field Test Of Giant Magnetostrictive Acoustic Wave Seismic Source,
2020
Faculty of Electrical and Control Engineering, Liaoning Technical University, Huludao 125106, China
Study On Time-Frequency Characteristics And Field Test Of Giant Magnetostrictive Acoustic Wave Seismic Source, Wang Zelun, Gao Hongxin, Yu Shijian, Wang Yongshen
Coal Geology & Exploration
Wide-band, high-power and short-residual acoustic wave sources are the key technology for high-resolution detection of large-scale complex structures, in order to solve the contradiction between detection distance and resolution, a new acoustic wave detection instrument is developed by using the acoustic transmitter made of giant magnetostrictive material(GMM) as the source. The focal center frequency is 5 kHz, and the excitation voltage is 300-600 V, it has the characteristics of large radiated sound power, short residual vibration(3.5 cycles) and frequency band width(1-3 kHz), which solves the problem of the high resolution acoustic wave detection. Its greatest advantage is that the acoustic …
