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Articles 2551 - 2580 of 5557
Full-Text Articles in Oil, Gas, and Energy
Effect Of Acidification On The Microstructure And Physical Properties Of Shale, Chen Liuyu, Li Xijian, Shen Zhonghui, Xu Shiqing, Ma Shengxiang, Yin Xin
Effect Of Acidification On The Microstructure And Physical Properties Of Shale, Chen Liuyu, Li Xijian, Shen Zhonghui, Xu Shiqing, Ma Shengxiang, Yin Xin
Coal Geology & Exploration
As the main shale gas reservoir in Guizhou, it is proved that Longmaxi Formation has good shale gas accumulation conditions and resource development potential. In order to reveal the response law of acidification on the micropore structure and physical properties of Longmaxi Formation shale in Guizhou, the difference in physical properties of shale microstructures before and after acidification, such as pore volume, porosity, specific surface area and pore size distribution was quantitatively characterized by X-ray diffraction(XRD) analysis, mercury intrusion measurement, low-temperature nitrogen adsorption and nuclear magnetic resonance(NMR) experiment. The structural characteristics of the shale pores before and after acidification were …
Application Of Time Series Model In Water Inflow Prediction Of Working Face, Shi Longqin, Wang Yaru, Qiu Mei, Gao Weifu
Application Of Time Series Model In Water Inflow Prediction Of Working Face, Shi Longqin, Wang Yaru, Qiu Mei, Gao Weifu
Coal Geology & Exploration
In practical production of mines, the prediction of mine water inflow is of great significance for mine water prevention and control. Taking working face 1301 of Yuncheng coal mine as the research object, and without considering the influence of seasonal factors, ARIMA-the time series analysis model-is used to establish the functional relationship between mine water inflow and time, which proves that the time series of water inflow in working face 1301 of Yuncheng coal mine is affected by seasonal factors. Then, based on the principle of addition and decomposition of time series, the long-term trend, seasonal indexes, circulating factors and …
Development Characteristics Of Water Conducted Fracture Zone Based On Overburden Structural Effect, Cao Zubao, Wang Qingtao
Development Characteristics Of Water Conducted Fracture Zone Based On Overburden Structural Effect, Cao Zubao, Wang Qingtao
Coal Geology & Exploration
In order to study the roof water disaster caused by coal mining in Huanglong coalfield, taking mining failure of layered overburden as research object, four typical composite structural models for coal-soft rock-hard rock-soft rock-hard rock(combination I), coal-soft rock-soft rock-hard rock-hard rock(combination Ⅱ), coal-hard rock-soft rock-hard rock-soft rock(combination Ⅲ) and coal-hard rock-hard rock-soft rock-soft rock(combination IV) were generalized. Numerical simulation and theoretical calculation were used to analyze the mining failure characteristics of different overburden combinations and correlation between water conducting fissures and lithologic combination structure of overburden. The law of the effect of overburden structure on the development height of water …
The Law Of Soaking Infiltration And Collapse Deformation In Typical Loess-Paleosol Series, Zhao Jingang, Lyu Yuanqiang, Chao Jun, Yang Zhe, Xia Meng
The Law Of Soaking Infiltration And Collapse Deformation In Typical Loess-Paleosol Series, Zhao Jingang, Lyu Yuanqiang, Chao Jun, Yang Zhe, Xia Meng
Coal Geology & Exploration
In order to investigate the law of moisture migration and collapse deformation of the typical loess-paleosol series, on the basis of water immersion test of the large test pits of Xi’an North-airport intercity rail transit in the loess tableland of Weibei, the real-time in-site observation was adopted, the soaking infiltration and collapse deformation of collapsible soil layer under conditions of non water seepage hole were traced and tested. The results show that: The movement of water immersion is dominated by vertical movement in the early stage. The whole form is like a continuous increase of “weight” shape. As the water …
Numerical Calculation Of Temperature Field Of Freeze-Sealing Pipe Roof Method In Gongbei Tunnel, Long Wei, Rong Chuanxin, Duan Yin, Guo Ke
Numerical Calculation Of Temperature Field Of Freeze-Sealing Pipe Roof Method In Gongbei Tunnel, Long Wei, Rong Chuanxin, Duan Yin, Guo Ke
Coal Geology & Exploration
This paper took the Gongbei tunnel in the Zhuhai Connection Section of the Hong Kong-Zhuhai-Macao Bridge as an example to study the development of the temperature field of the Freeze-Sealing Pipe Roof Method. Based on the heat transfer theory of two-dimensional porous media, the FEM software COMSOL was used to numerically analyze the actual working conditions of the active freezing period, the numerical calculation was verified by field measurement. The development and distribution of the temperature field before and after the opening of the special-shaped freezing pipes was studied. The results showed that: when freezing for 30 days, the concrete …
Detection Technique And Application Of Transmission In-Seam Wave In Thin Coal Seam, Yang Hui
Detection Technique And Application Of Transmission In-Seam Wave In Thin Coal Seam, Yang Hui
Coal Geology & Exploration
Aiming at the problem of serious attenuation of channel wave in thin seam and its limited distance of propagation, a method of restricted CT imaging was proposed by using the furthest in-seam wave propagation distance. Firstly, the variation of in-seam wave frequency with different thickness of coal seam was studied by theoretical derivation. Taking a 1.5m thin seam as the main research object, the attenuation characteristics of channel wave were simulated by forward modeling, and the effective propagation distance of channel wave was determined. The actual data of No. 15 coal seam in a coal mine in Shandong Province shows …
Common Midpoint Gather Constraint-Based Impedance Inversion Of Ground Penetrating Radar, Dai Qianwei, Ning Xiaobin, Zhang Bin
Common Midpoint Gather Constraint-Based Impedance Inversion Of Ground Penetrating Radar, Dai Qianwei, Ning Xiaobin, Zhang Bin
Coal Geology & Exploration
GPR impedance inversion is an effective method to obtain accurately the intrinsic parameters of the subsurface medium. This method relies on low frequency information provided by logging data, but it is rarely accompanied by drilling in practical applications. To solve the problem, the common midpoint velocity analysis is employed to provide more low frequency component information for impedance inversion of GPR to finely reconstruct the dielectric parameter of subsurface in the framework of velocity-constrained inversion technique. Firstly, a layer model is specifically set up as an example to verify the feasibility of the developed velocity- constrained inversion to regulate the …
Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff
Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff
Faculty Publications
Biodiesel offers several environmental benefits and improvements to some fuel performance properties, but its poor oxidative stability has been a major concern. Currently, the accepted practice to improve biodiesel oxidative stability is the addition of antioxidants; numerous antioxidants have been studied but their effectiveness in inhibiting biodiesel oxidation is difficult to predict due to variation with resonance stability, solubility, reactivity, and volatility. To improve prediction efforts, this study explored the Rapid Small-Scale Oxidation Test (RSSOT) as a means to investigate how biodiesel oxidation is affected by antioxidant concentration and temperature, and compared its results with the oxidative stability index test. …
Techno-Economic Analysis Of Floating Offshore Airborne Wind Energy Systems In The Gulf Of Mexico, Alexandria Savannah Leake
Techno-Economic Analysis Of Floating Offshore Airborne Wind Energy Systems In The Gulf Of Mexico, Alexandria Savannah Leake
LSU Master's Theses
Techno-economic analyses play an important role in determining locations for conventional wind turbine installations. This method is utilized to assess energy production potential for a new type of wind technology, known as airborne wind energy (AWE). The first objective of the present thesis was to determine overall investment potential of a utility-scale floating offshore airborne wind farm, testing five floating platform design concepts. The second objective was to determine whether the wind resources (100-1500 m) are ideal to support AWE systems in the Gulf of Mexico. Specifically, a hypothetical benchmark wind farm was developed 15 km offshore from Venice, Louisiana. …
Developing And Implementing A 100% Renewable Electricity Resolution: A Research-Based Framework, Emily E. Skill, Roslynn Brain Mccann, Sarah C. Klain
Developing And Implementing A 100% Renewable Electricity Resolution: A Research-Based Framework, Emily E. Skill, Roslynn Brain Mccann, Sarah C. Klain
All Current Publications
While it may seem that the efforts of local governments have only a marginal impact on the global issue of climate change, local action can spread to generate large-scale change. Local action can inspire other communities to adopt policies, creating the potential to expand and form regional action on climate change. Furthermore, local policies can influence state and federal policies. This guide will walk you through a five-step framework that was developed from the results of a qualitative research study that explored how three Utah cities, Salt Lake City, Park City, and Moab, successfully adopted 100% renewable electricity resolutions.
Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson
Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson
Electronic Theses and Dissertations
Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.
This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the Central …
A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila
A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila
Student Works (2020-2029)
Malay Basin is a prospective basin which perceived to be matured basin in terms of hydrocarbon generating potential. Many significant oil discoveries made since 1970’s includes Seligi, Pulai, Tapis and Bekok oil fields. These fields have been producing until now. Despite its matured stage, there are still more oil discoveries in various parts of Malay Basin until now. Oil discoveries include light and high density oils with various challenges in oil development project. This dissertation focuses on oil fields in East Malay Basin particularly Lerek, Chermingat, Lawang and Serudon oil fields. The objectives of this research are to study the …
Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh
Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh
Civil and Environmental Engineering and Construction Faculty Research
Considering environmental concerns regarding air pollution which is induced by burning fossil fuels to generate electrical power, utilizing solar energy as a green and sustainable energy source is of great interest. This study proposes a novel framework to determine the optimal location for constructing solar photovoltaic (PV) farms. To locate the suitable areas for PV farms, firstly, a fuzzy-based method is utilized to homogenize the input parameters, thereafter, the analytical hierarchy process (AHP) and Dempster-Shafer (DS) methods are independently used. In the AHP method, the proper weight for each input parameter is generated utilizing a pairwise comparison matrix. However, the …
Clean Alternatives For Household Coal - Case Study: Izmir, Turkey, Yagiz Yar
Clean Alternatives For Household Coal - Case Study: Izmir, Turkey, Yagiz Yar
Master's Projects and Capstones
Household coal consumption during the heating season affects Izmir’s air quality adversely to the point where air quality indicators show that pollution levels exceed limit concentration values that World Health Organization set for a habitable and healthy ambient air. The objective of this paper is to evaluate alternatives that utilize low-carbon emitting methods of domestic heating fueled by renewable energy sources and develop a model which would replace household coal. Research shows that 223,969 tonnes of coal were burned in households of Izmir in 2019 and analysis results show that 2.72 million MMBtu of heat energy was supplied to these …
A Review Of Methods To Better Predict And Reduce The Risk Of Hurricane Damage To The Energy Sector, Zackary Litalien
A Review Of Methods To Better Predict And Reduce The Risk Of Hurricane Damage To The Energy Sector, Zackary Litalien
Master's Projects and Capstones
In the event of a hurricane, electricity is the most important utility as it provides heat, water, food, light, communication, and medical care to communities. Research predicts an increase in frequency and strength of hurricanes with time due to climate change, which requires communities and electric utility companies to be prepared for the inevitable. This paper assesses existing methods of hurricane preparation and restoration of the electric power grid in hurricane prone locations with regards to the electric utility companies and electric distribution systems. In this study, I perform a comparative analysis between different methods of planning and forecasting electrical …
Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre
Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre
Life Sciences Faculty Research
As population and economies continue to grow on a global scale, so too does the demand for energy. To improve reliability and independence of energy supplies, the U.S. and many other countries are seeking internally-sourced renewable energy; solar is one such renewable-energy source that meets these criteria. However, all energy sources exert some environmental impacts. In the case of solar, direct impacts stem mostly from alteration of land needed to host infrastructure. Understanding the environmental upside and downside potential of solar energy systems allows a more comprehensive, side-by-side comparison with different energy sources. In this article, we focus on the …
Efficiency Analysis Of Harvesting Solar Energy To Perform Mechanical Work, Haden S. Bragg
Efficiency Analysis Of Harvesting Solar Energy To Perform Mechanical Work, Haden S. Bragg
Undergraduate Theses and Capstone Projects
The majority of the world’s electricity is generated using fossil fuels; in fact, the United States Energy Information Administration (EIA) states that the U.S. used fossil fuels to generate 62.7 % of its electricity in 2019 [1]. The goal of this research was to create a system that could perform mechanical work using only renewable resources. We built a solar charging station that uses two solar panels to generate electricity and an electric bicycle whose battery can be charged using the charging station. The efficiency for the type of solar cell used in this project is well established. Therefore, in …
An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald
An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald
Honors Scholar Theses
The purpose of this project is to design a clean energy-sourced microgrid for UConn’s main campus that would reduce the university’s energy emissions while remaining within the geographic boundaries of viable UConn-owned land. Economic cost was not considered in this analysis; instead, emissions and space constraints were the optimized measures of value and feasibility. Sources of energy that were considered include photovoltaics (PV), wind turbines, hydrokinetic systems, and fuel cells. Energy storage capacity was included in the analysis as well. The overall system was optimized first by ignoring space constraints and for a minimum of 10% reduction from the current …
Negative Power Rock Strength Criterion Under Conventional Triaxial Compression, Li Bin, Wang Daguo
Negative Power Rock Strength Criterion Under Conventional Triaxial Compression, Li Bin, Wang Daguo
Coal Geology & Exploration
In order to evaluate accurately the rock strength under different confining pressures, a negative power rock strength criterion was proposed according to the upward convex nonlinear relationship between deviator stress and confining pressure during rock failure. The accuracy of the proposed criterion was compared with Mohr-Coulomb criterion and Hoek-Brown criterion. The results showed that the parameters of the negative power criterion are less sensitive to the range of confining pressure, and the negative power criterion could evaluate rock triaxial strength with higher precision. Meanwhile, the applicability of the proposed criterion was verified by using an extensive database of rock triaxial …
Foam Drilling Technology And Application For Broken Soft Coal Seam In Underground Coal Mine, Ji Qianhui, Dong Mengmeng, Liu Jianlin, Shi Lei
Foam Drilling Technology And Application For Broken Soft Coal Seam In Underground Coal Mine, Ji Qianhui, Dong Mengmeng, Liu Jianlin, Shi Lei
Coal Geology & Exploration
Aiming at the limitation of middle pressure air drilling for gas drainage in soft and broken coal seam, such as limited drill cutting removal capacity, and dust pollution, foam drilling technique research in underground coal mines was carried out. CFD simulation of the flow field during the drilling process was conducted to obtain the optimized drilling tool structure parameters for efficient drill cutting transportation. Optimal structural parameters of wide-blade milled auger drill rod with the number of heads 3, the groove width 26 mm, and the pitch 110 mm were determined. A foam perfusion system suitable for underground coal mining …
Influencing Factors Of Thermal Conductivity Of Cementing Materials For Geothermal Wells, Zhang Hao, Xu Shuanhai, Yang Yu, Han Yongliang, Zhang Weidong, Li Yongqiang
Influencing Factors Of Thermal Conductivity Of Cementing Materials For Geothermal Wells, Zhang Hao, Xu Shuanhai, Yang Yu, Han Yongliang, Zhang Weidong, Li Yongqiang
Coal Geology & Exploration
The thermal conductivity of cementing materials is one of the factors that affect the heat removal effect of geothermal wells. In order to improve the thermal conductivity of cementing materials for geothermal wells, orthogonal test was used to study the thermal conductivity of cementing materials based on the AHP-CRITIC mixed weighting method and range analysis. The results show that the thermal conductivity of cementing materials can be improved by adding natural flake graphite, iron powder and quartz sand. The content of graphite and the ratio of water to solid are the primary and secondary factors that affect the comprehensive properties …
Progress Of Drilling Technologies And Equipments For Complicated Geological Conditions In Underground Coal Mines In China, Yao Ningping, Wang Yi, Yao Yafeng, Song Haitao, Wang Li, Peng Tao, Sun Xinsheng
Progress Of Drilling Technologies And Equipments For Complicated Geological Conditions In Underground Coal Mines In China, Yao Ningping, Wang Yi, Yao Yafeng, Song Haitao, Wang Li, Peng Tao, Sun Xinsheng
Coal Geology & Exploration
According to the drilling technology requirements and problems under complicated geological conditions, such as broken soft coal seam, hard rock, rockburst strata, fractured zone, water-sensitive strata, etc, the research and application of drilling technology and screen pipe protection in broken soft coal seam, comb-like directional drilling technology in broken soft coal seam, high-level directional drilling technology in complicated roof strata, full-section across-layer drilling technology of hard rock, and drilling technology for pressure relief in rockburst strata were summed. This paper puts forward the research approaches of the technology and equipment of double-pipes directional drilling and rotary directional drilling in broken …
Ato Mode-Based Modular Platform Development Of Variable Luffing Crawler Drilling Rig Used In Underground Coal Mine, Song Haitao, Yao Ningping, Yao Yafeng, Han Jian, Peng Tao
Ato Mode-Based Modular Platform Development Of Variable Luffing Crawler Drilling Rig Used In Underground Coal Mine, Song Haitao, Yao Ningping, Yao Yafeng, Han Jian, Peng Tao
Coal Geology & Exploration
With the continuous popularization of customized crawler rigs in coal mines, the variety and specifications of crawler rigs have been further refined, diversified and complicated, and the modular platform of variable luffing crawler rigs has been successfully developed. The four key steps in the development of modular platform were analyzed: the construction of modular platform, the rational division and development of modular components, the integration and development of modular components, the modular customization model for customers based upon the proposed ATO-based model. The application results show that the establishment of the variable luffing crawler rig modular platform shortens respond to …
Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin
Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin
Coal Geology & Exploration
Aiming at the problems of large drilling pressure, low drilling efficiency and limited hole depth caused by the backing effect of drill string during deep hole directional drilling in underground coal mine, the technical idea of using hydraulic agitator was proposed. The ø89 mm small diameter hydriculic agitator was designed based on valve principle, the exciting force, excitation frequency were identified, and the cabled sub was developed. The performance parameters of hydraulic agitator with disc spring and cylindrical spring were tested. The results show that when the flow rate of 300 L/min the disc spring hydraulic agitator has the maximum …
Causes Of Anomaly Of Rare Earth Elements Of Seam 2 Of Yan’An Formation In The Northern Margin Of Ordos Basin And Its Geological Significance, Yang Yi, Lyu Dawei, Zhang Jianqiang, Wu Dun
Causes Of Anomaly Of Rare Earth Elements Of Seam 2 Of Yan’An Formation In The Northern Margin Of Ordos Basin And Its Geological Significance, Yang Yi, Lyu Dawei, Zhang Jianqiang, Wu Dun
Coal Geology & Exploration
The cause of rare earth elements(REE) anomalies in No.2 coal seam of the Yan’an Formation in the northern margin of the Ordos basin has been controversial. This paper takes Dahaize coal mine, Yulin area with well developed No.2 coal as an example to analyze REE, mineralogical characteristics of coal and partings, and to reveal the causes of anomaly of REE by Inductive Coupled Plasma Mass Spectrometry(ICP-MS) and Scanning Electron Microscopy(SEM). The results show that the total rare earth element(∑REE) concentration in the coal samples ranges from 3.71 to 46.21 μg/g. Light rare earths elements(LREE, La-Eu) are more abundant than heavy …
Mineralogical Characteristics And Genesis Of The Illite In Jurassic Coal Of The Jingxi Coalfield, North China, Huang Bo, Zheng Qiming, Shi Songlin
Mineralogical Characteristics And Genesis Of The Illite In Jurassic Coal Of The Jingxi Coalfield, North China, Huang Bo, Zheng Qiming, Shi Songlin
Coal Geology & Exploration
In order to study the indicating effect of illite for coalification and sedimentary environments, the Jurassic coal seam gangue in Jingxi coalfield of North China was taken as the research object. X-ray diffraction(XRD) and X-ray fluorescence(XRF) were used to determine the mineral composition and chemical composition of the gangue sandwiched in the coal seam gangue. The mineralogical characteristics and genesis of illite in the gangue were studied. The results indicated that the intra-seam partings are mainly composed of illite, chlorite and quartz, followed by small amount of calcite and albite. The illite has an average proportion of 62.92%. According to …
Changes Of Petrographic Characteristics And Quality Of Contact-Metamorphosed Coals In The Datong Coalfield, Ma Hongtao, Song Xiaoxia, Li Kaijie, Zhao Jingui, Zhang Tianguang, Liu Jianping
Changes Of Petrographic Characteristics And Quality Of Contact-Metamorphosed Coals In The Datong Coalfield, Ma Hongtao, Song Xiaoxia, Li Kaijie, Zhao Jingui, Zhang Tianguang, Liu Jianping
Coal Geology & Exploration
Igneous intrusions in the Datong coalfield caused a considerable amount of contact metamorphosed coal, reducing the industrial value of coal. The effect of a dike in roadway 5222 in Tashan coal mine was determined from analysis of 16 samples collected near the intrusive body. Microscopic and macroscopic observation, proximate and ultimate analysis were used to determine the petrographic characteristics. The results demonstrate that contact-metamorphosed coal experienced significant thermal alteration during intrusive event. Microscopically, various natural coke microstructures, such as mosaic structure, flow structure and pyrolytic carbon were formed under excess heat; instant heating for coals resulted in the elevation of …
Numerical Simulation Of Layer-Crossing Propagation Behavior Of Hydraulic Fractures At Coal-Rock Interface, Li Haozhe, Jiang Zaibing, Shu Jiansheng, Fan Yao, Du Tianlin
Numerical Simulation Of Layer-Crossing Propagation Behavior Of Hydraulic Fractures At Coal-Rock Interface, Li Haozhe, Jiang Zaibing, Shu Jiansheng, Fan Yao, Du Tianlin
Coal Geology & Exploration
Based on the analysis of coal-rock interface, the vertical propagation behavior of hydraulic fractures at coal-roof interface was studied by using finite element method. The influence of some geological and engineering factors on fracture layer-crossing behavior was analyzed. Results have shown that in-situ stress and shear strength of coal-rock interface are the two main factors affecting the fracture propagation at the coal-rock interface. Greater vertical stress difference coefficient and interfacial shear strength make fractures more easier for crossing the interface. Meanwhile, the difference of elastic modulus and tensile strength between coal and rock has less effect on the fracture vertical …
Creep Acoustic Emission And Fractal Characteristics Of Coal Rock Under High Temperature Pre-Damage, Shi Hongcai
Creep Acoustic Emission And Fractal Characteristics Of Coal Rock Under High Temperature Pre-Damage, Shi Hongcai
Coal Geology & Exploration
The thermal damage and triaxial creep acoustic emission experiments of coal samples at different temperatures were carried out to investigate and analyze the mechanical characteristics of coal and rock after high temperature pre-damage. The results show that the thermal damage of coal and rock increases exponentially with the increase of temperature; the brittle-ductile failure characteristics of coal and rock appear at lower temperature(≤200℃) and the accelerated creep characteristics are not obvious; the brittle-brittle failure characteristics of coal and rock appear at higher temperature(>200℃) and the accelerated creep characteristics are more obvious; the value of steady creep rate is between pre-damage …
Progress In Research Of In-Seam Seismic Exploration, Guo Yinjing, Ju Yuanyuan, Fan Xiaojing, Zhang Jianhua
Progress In Research Of In-Seam Seismic Exploration, Guo Yinjing, Ju Yuanyuan, Fan Xiaojing, Zhang Jianhua
Coal Geology & Exploration
after long-term development and improvement, the in-seam seismic(ISS) technology has achieved relatively reliable results in detecting the internal structural development of the coal seam, the thickness variation of the coal seam, and the distribution pattern of the pinch. In order to comprehensively and systematically understand the ISS technology and promote the development of the ISS technology, the status of the ISS technology is reviewed. First, the principle of ISS is briefly described. Then, according to the process of ISS, according to the steps of source excitation, signal acquisition, preprocessing, signal extraction, data processing and analysis, the working principles and methods …