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Articles 841 - 870 of 6952
Full-Text Articles in Engineering
Dynamic Evolutionary Pattern Of Fractures In Tectonically Deformed Coal-Bearing Assemblages During Loading, Zhao Pengxiang, Liu Yingying, Li Shugang, Liu Yanqun, Liu Yunchuan, Wang Laolao, Lu Weidong
Dynamic Evolutionary Pattern Of Fractures In Tectonically Deformed Coal-Bearing Assemblages During Loading, Zhao Pengxiang, Liu Yingying, Li Shugang, Liu Yanqun, Liu Yunchuan, Wang Laolao, Lu Weidong
Coal Geology & Exploration
Objective The formation and evolution of fractures in tectonically deformed coals (TDCs) exert a significant influence on the occurrence of dynamic hazards to TDC-bearding combinations under mining disturbance. However, the influence patterns remain unclear. Methods Using a NanoVoxel-3000 high-resolution inspection system for multiscale integrated geotechnical scanning and analysis, this study performed uniaxial compression and CT scanning experiments on TDC-bearing combination specimens. Moreover, this study reconstructed the mesoscopic geometric structures of the specimens using the Avizo software, obtaining three-dimensional visualization models of fractures inside the specimens. Results and Conclusions During loading of a specimen studied, fractures were generated in the TDC …
A New Quantitative Assessment Model For The Joint Roughness Of Rock Masses, Chen Shijiang, Liu Hongwei, Li Tao, Yue Hu, Liu Jiangang, Yu Jiang
A New Quantitative Assessment Model For The Joint Roughness Of Rock Masses, Chen Shijiang, Liu Hongwei, Li Tao, Yue Hu, Liu Jiangang, Yu Jiang
Coal Geology & Exploration
Objective The joint roughness of rock masses significantly affects their mechanical properties such as shear strength and permeability. Therefore, its quantitative characterization is significant for the engineering practices of jointed rock masses. Current research achievements indicate that among statistical parameters, the root mean square (RMS) of first derivatives (Z2) exhibits the strongest correlation with the joint roughness of rock masses, serving as a vital method for characterizing joint roughness. However, the characterization using this parameter is severely affected by the sampling interval (SI). Methods Based on a systematic analysis of the drawbacks of Z2 in characterizing …
Zonal Prediction Of The Heights Of Water-Conducting Fracture Zones Under Varying Overburden Types In North China-Type Coalfields, Xu Dongjing, Zhang Ruiqing, Gao Weifu, Jiang Haonan, Zhu Haifeng, Li Ye, Xia Zhicun
Zonal Prediction Of The Heights Of Water-Conducting Fracture Zones Under Varying Overburden Types In North China-Type Coalfields, Xu Dongjing, Zhang Ruiqing, Gao Weifu, Jiang Haonan, Zhu Haifeng, Li Ye, Xia Zhicun
Coal Geology & Exploration
Background The gradual increase in the exploitation depth and intensity of coal resources in the North China-type coalfields has caused problems such as overburden movement and damage, as well as fracture evolution. These hot topics have attracted considerable attention. Methods A total of 117 sets of measured data on the heights of water-conducting fracture zones in the North China-type coalfields were collected, consisting of 17 sets from hard overburden, 42 sets from moderately hard overburden, and 58 sets from soft overburden. Using these data, this study explored the effects of varying mining heights, mining depths, and lengths of the mining …
A Method For Time Difference Correction For Real-Time Seismic-While-Mining Data, Jin Dan
A Method For Time Difference Correction For Real-Time Seismic-While-Mining Data, Jin Dan
Coal Geology & Exploration
Objective Seismic-while-mining (SWM) data are usually acquired using multiple stations, each of which is equipped with multiple data acquisition traces. However, the SWM data received by these stations exhibit time differences due to the lack of GPS signals underground and the fact that current network synchronization technologies are confined by network delays underground. Given that the time synchronization accuracy directly affects the quality of data processing and imaging, the time difference correction of real-time SWM data is essential for accurate SWM detection. Methods Since current high-precision timing systems on the surface suffer from signal loss underground, this study proposed an …
Influencing Mechanisms Of Microwave Radiation Duration On The Efficiency Of Methane Adsorption In Coals, Hu Yiliang, Bao Yuan, Meng Jiahao, Chen Xueru, Shan Tuo
Influencing Mechanisms Of Microwave Radiation Duration On The Efficiency Of Methane Adsorption In Coals, Hu Yiliang, Bao Yuan, Meng Jiahao, Chen Xueru, Shan Tuo
Coal Geology & Exploration
Objective Microwave radiation duration represents a critical factor in enhancing coalbed methane (CBM) recovery using microwave-aided methods. However, the influencing mechanism of microwave radiation duration on the efficiency of methane adsorption in coal seams remains unclear. This necessitates delving into the specific effects of microwave radiation duration on the adsorption efficiency and unveiling their intrinsic constraints. Methods This study investigated the No.2 coal seam in the Huangling mining area. The coal samples were irradiated for 0‒18 min using 700 W microwaves. Using experiments and analyses including isothermal adsorption, low-temperature liquid N2 adsorption, and Fourier transform infrared spectroscopy (FTIR), this study …
Assessment Indicator System For Siting Of Geologic Co2 Sequestration In Low-Porosity And Low-Permeability Saline Aquifers: A Case Study Of The Ordos Basin, Mou Yu, Wang Haofan, Shaanxi Key Laboratory For Carbon Neutral Technology, Carbon Neutrality College (Yulin), Northwest University, Xi’An 710069, China Xuejun, Ma Jinfeng, Luo Shaocheng, Li Lin, Ding Zhao
Assessment Indicator System For Siting Of Geologic Co2 Sequestration In Low-Porosity And Low-Permeability Saline Aquifers: A Case Study Of The Ordos Basin, Mou Yu, Wang Haofan, Shaanxi Key Laboratory For Carbon Neutral Technology, Carbon Neutrality College (Yulin), Northwest University, Xi’An 710069, China Xuejun, Ma Jinfeng, Luo Shaocheng, Li Lin, Ding Zhao
Coal Geology & Exploration
Objective CO2 injection and geologic sequestration in deep saline aquifers as underground spatial resources represents an important means of achieving the targets of greenhouse gas emission reduction and carbon neutrality. Current assessments of the siting and potential for geologic CO2 sequestration in saline aquifers focus primarily on the macroscopic basin and regional scales, with the assessment indicator system scarcely accounting for the suitability of low-porosity and low-permeability strata. Methods Using data from 192 wells in the Yusheng area, Ordos Basin, this study conducted the division and correlation of intervals bearing no hydrocarbon, carried out lithologic and physical interpretations …
Optimization And Application Of Sand Bailing Technology For Coalbed Methane Horizontal Wells, Zhang Fei, Wang Yibing, Cheng Lu, Mei Wenbo, Yang Qi, Shen Wenjie, Cao Chao, Lai Peng, Liao Zhengkai, Xian Bao'an, Bi Yansen
Optimization And Application Of Sand Bailing Technology For Coalbed Methane Horizontal Wells, Zhang Fei, Wang Yibing, Cheng Lu, Mei Wenbo, Yang Qi, Shen Wenjie, Cao Chao, Lai Peng, Liao Zhengkai, Xian Bao'an, Bi Yansen
Coal Geology & Exploration
Objective and Methods Coalbed methane (CBM) horizontal wells face challenges such as sand accumulation in completion strings, pipe wall scaling, and pump sticking, leading to declined CBM production or shutdown of these wells. This severely restricts continuous, stable CBM production. Removing pulverized coals and sands from wellbores through mechanical sand bailing is recognized as an effective technique to restore and improve the CBM production of horizontal wells. To address challenges such as poor string sealing performance, low efficiency, and sand consolidation in mechanical sand bailing, this study created optimized tools including claw-shaped scraper tips, sand-breaking drill bits, eccentric flaps, and …
Application Of A Generative Adversarial Network Algorithm To Filling Blank Strips Of Fractures In Formation Microresistivity Imaging Images, Kang Zhengming, Wu Chensheng, Yang Guodong, Wu Disheng, Wang Ruifei, Yang Xiangyu, Gan Wei
Application Of A Generative Adversarial Network Algorithm To Filling Blank Strips Of Fractures In Formation Microresistivity Imaging Images, Kang Zhengming, Wu Chensheng, Yang Guodong, Wu Disheng, Wang Ruifei, Yang Xiangyu, Gan Wei
Coal Geology & Exploration
Objective Gaps between the electrodes of formation microresistivity imaging (FMI) imagers lead to blank strips in the resistivity images of borehole walls, significantly influencing the parameter assessment for fractures near borehole walls. The absence of full-borehole images renders it challenging to assess the blank strip filling quality for fractures in FMI images. Using a dataset constructed utilizing both simulated and actual data, this study proposed a generative adversarial network (GAN)-based method for filling the blank strips of fractures in FMI images. Methods First, the resistivity logging responses of a fractured formation were simulated using the 3D finite element method. Actual …
An Edge Awareness-Enhanced Visual Slam Method For Underground Coal Mines, Mu Qi, Liang Xin, Guo Yuanjie, Wang Yuhao, Li Zhanli
An Edge Awareness-Enhanced Visual Slam Method For Underground Coal Mines, Mu Qi, Liang Xin, Guo Yuanjie, Wang Yuhao, Li Zhanli
Coal Geology & Exploration
Objective Underground coal mines commonly exhibit low illuminance, weak textures, and structuralization-induced feature degradation. These scenes lead to challenges of insufficient effective features and high mismatch rates to the visual simultaneous localization and mapping (SLAM) system, severely compromising its localization accuracy and robustness. Methods This study proposed an edge awareness-enhanced visual SLAM method. First, an edge-awareness constrained low-illuminance image enhancement module was developed. Specifically, images with clear textures and uniform illumination were obtained using the Retinex algorithm optimized using an adaptive gradient-domain guided filter. This significantly improved feature extraction performance under low and uneven lighting conditions. Second, an edge awareness-enhanced …
Solving A Multi-Stage Mine Sequencing Model Encompassing Excavator Allocation Through Constraint Programming In A Bauxite Strip Mining Operation, Jorge Luiz Valença Mariz, Marcel Antonio Arcari Bassani, Rodrigo De Lemos Peroni, Octávio R. A. Guimarães, Flávio H. Tavares
Solving A Multi-Stage Mine Sequencing Model Encompassing Excavator Allocation Through Constraint Programming In A Bauxite Strip Mining Operation, Jorge Luiz Valença Mariz, Marcel Antonio Arcari Bassani, Rodrigo De Lemos Peroni, Octávio R. A. Guimarães, Flávio H. Tavares
Journal of Sustainable Mining
Sedimentary mineral deposits are generally tabular and sub-horizontal, composed of one or multiple well-defined seams, arranged over large extensions, and when close to the surface, they are mined by surface mining methods. These geometric characteristics make it suitable for the application of the strip mining method as an alternative to the traditional open-pit mining method, which allows the reduction of the truck haulage fleet and the costs associated with waste disposal. Consequently, it reduces the greenhouse gas emissions and carbon footprint associated with excavation and transportation processes. This article presents a two-stage mathematical model based on Integer Linear Programming to …
Challenges In Artisanal Small-Scale Gold Mining: Perspectives And Transformations To Sustainability Along Br-163 In Brazil, Carlos Henrique Xavier Araujo, Irfan Ullah, Giorgio De Tomi
Challenges In Artisanal Small-Scale Gold Mining: Perspectives And Transformations To Sustainability Along Br-163 In Brazil, Carlos Henrique Xavier Araujo, Irfan Ullah, Giorgio De Tomi
Journal of Sustainable Mining
Artisanal Small-scale Gold Mining (ASGM) is a sector beset with unique and complex challenges. Recent literature highlights the growing acknowledgment of the critical need for reforms in how the ASGM industry interacts with communities and the environment. Discussions about sustainable transformations go beyond theoretical and conceptual borders, attempting to understand how local transformative events might reflect global developments. Thus, the goal of this article is to give an analysis from the perspective of the actors participating in artisanal gold mining activities. A survey was carried out along BR-163, which runs from Sinop (Mato Grosso) to Santarém (Pará). Fifty-five (55) interviews …
Magnetic And Optical Properties Of Airborne Dust Particles Nearby Coal-Fired Power Plants In Upper Silesia, Poland: A Mineralogical, Petrographical And Chemical Approach, Chrysoula Chrysakopoulou, Konstantinos Perleros, Małgorzata Wojtaszek-Kalaitzidi, Lambrini Papadopoulou, Nikolaos Kantiranis, Stavros Kalaitzidis
Magnetic And Optical Properties Of Airborne Dust Particles Nearby Coal-Fired Power Plants In Upper Silesia, Poland: A Mineralogical, Petrographical And Chemical Approach, Chrysoula Chrysakopoulou, Konstantinos Perleros, Małgorzata Wojtaszek-Kalaitzidi, Lambrini Papadopoulou, Nikolaos Kantiranis, Stavros Kalaitzidis
Journal of Sustainable Mining
Coal mining and exploitation pose certain challenges in terms of environmental management. The objective of this research is the study of airborne dust from Knurow region, Southern Poland, aiming to identify the level and the features of anthropogenic particles, mostly in the form of fly ash. Two samples collected from a domestic gutter system were analysed regarding their mineralogical, chemical and petrographical features, emphasizing the magnetic fraction and the carbonized organic particles. The airborne dust contains 22 wt.% of fossil and fresh organic matter, whereas the major mineralogical phase is magnetite. The magnetic fraction (up to 3 wt.%) appears in …
Prediction Of Unit Haulage Cost In An Underground Mine Using Machine Learning Techniques, Marco Cotrina, Jairo Marquina, Junior Polo
Prediction Of Unit Haulage Cost In An Underground Mine Using Machine Learning Techniques, Marco Cotrina, Jairo Marquina, Junior Polo
Journal of Sustainable Mining
The primary objective of the research was to apply machine learning techniques to forecast the unit costs of ore hauling in an underground mine. The methodology employed was quantitative, with a non-experimental and descriptive design. Haulage data were collected over a 12-month period. Furthermore, an exploratory data analysis (EDA) was conducted using various models, including ANN-MLP (Artificial Neural Network – Multilayer Perceptron), Random Forests, Extreme Gradient Boosting, Support Vector Regression, Decision Tree, KNN, and Bayesian Regression, to handle the data’s complexity. The data were split into 80% for training, 10% for testing, and 10% for validation. The results indicated that …
Enhancing The Efficiency Of Eaop Degradation Using Ultrasound: A Study With Methylene Blue And Pfoa As Model Pollutants, Jamiu Busayo Ahmed
Enhancing The Efficiency Of Eaop Degradation Using Ultrasound: A Study With Methylene Blue And Pfoa As Model Pollutants, Jamiu Busayo Ahmed
Master's Theses
No abstract provided.
Evaluating Atmospheric Water Generation For The Indo-Pacific: Predictive Modeling, Energy Considerations, And Regional Viability, Jose I. De La Serna
Evaluating Atmospheric Water Generation For The Indo-Pacific: Predictive Modeling, Energy Considerations, And Regional Viability, Jose I. De La Serna
Theses and Dissertations
Atmospheric Water Generator (AWG) technology presents a promising solution for extracting and harvesting water from ambient air through condensation methods. This innovative approach offers a viable alternative for water production in regions with limited or unreliable water sources. AWGs operate most effectively in hot and humid environments, typically at temperatures of 80°F and relative humidity levels of 80%. As of 2020, the Department of Defense (DoD) has identified the Indo-Pacific region as a strategic focus for addressing future greatpower competition. Within the framework of Agile Combat Employment, this study evaluates the feasibility and performance of AWG technology at pre-determined locations …
Assessing The Feasibility Of Managed Aquifer Recharge For The United States Air Force, Daniel Hendrix
Assessing The Feasibility Of Managed Aquifer Recharge For The United States Air Force, Daniel Hendrix
Theses and Dissertations
Water stress is becoming an increasing global issue, with 4 billion people (50% of the world’s population) experiencing water stress at least one month per year. By 2050, 60% of the world’s population and $70 trillion USD in global gross domestic product will be affected. This research analyzes 78 CONUS USAF installations to determine location-specific water stress and feasible Managed Aquifer Recharge (MAR) solutions. Although thousands of MAR projects have been implemented globally, active-duty USAF installations have yet to contribute to solving this growing issue. Important factors such as required subsurface conditions, physical limitations, design, cost, and regulatory constraints are …
Refining Chlorosulfonation Methods For The Synthesis Of A Perfluoroalkyl Arylsulfonimide (Pfsi) Monomer, Ainsley P. Foster, Ben Varney, Hua Mei
Refining Chlorosulfonation Methods For The Synthesis Of A Perfluoroalkyl Arylsulfonimide (Pfsi) Monomer, Ainsley P. Foster, Ben Varney, Hua Mei
SPARK Symposium Presentations
Proton-exchange membrane (PEM) fuel cells are sources of energy that are clean, quiet, and highly responsive to changes in power needs, making them promising for use in automobiles and other portable power devices. The electrolyte of a PEM cell–the layer responsible for conductivity–is a polymer membrane, commonly consisting of perfluoroalkyl sulfonic acid (PFSA) polymers. In place of the PFSA polymers, perfluoroalkyl arylsulfonimide (PFSI) polymers are expected to improve the efficiency of PEM fuel cells with better stability and proton conductivity. The trifluovinylether (TFVE) aryl perfluorosulfonamide monomer is a new PFSI monomer proposed to fulfill these benefits once polymerized. The previous …
Modelled Flooding Impacts On Lower Fish River Watershed, Sebastian Loschner
Modelled Flooding Impacts On Lower Fish River Watershed, Sebastian Loschner
Shelby Hall Graduate Research Forum Posters
This study investigates the impacts of compound flooding in the Lower Fish River watershed, Baldwin County, Alabama, with a focus on the potential effects of sea level rise due to climate change. Coastal flooding, particularly in smaller watersheds, is a growing concern as it results from the interaction of multiple factors, including rainfall, tidal changes, and extreme weather events. Compound flooding, which involves multiple flood drivers, is expected to worsen with climate change, as increased precipitation and rising sea levels create heightened flood risks. However, existing research on compound flooding predominantly focuses on large-scale watersheds, leaving a knowledge gap in …
Atmospheric Water Generation: Experimental Observations And Assembly Of An Artificial Neural Network, Houston Hoss Anderson
Atmospheric Water Generation: Experimental Observations And Assembly Of An Artificial Neural Network, Houston Hoss Anderson
Theses and Dissertations
This research investigated the performance of a Tsunami T50 Vapor Compression Cycle styled Atmospheric Water Generation (AWG) machine operated under ambient conditions in Dayton, Ohio. Water yield from the device was measured volumetrically and these values are paired with respective weather data, collected from a local monitoring station, to build an Artificial Neural Network in MATLAB and JMP software. Water yield varied over the course of this study but averaged 1.2L and maxed at 5L for 4-hour operating periods. This work is part of a 3-year project; future data is needed to enhance both training and validation of the model …
Investigation Of Methane Content And Sorption Properties Of Lignite Deposits, Marcin Karbownik
Investigation Of Methane Content And Sorption Properties Of Lignite Deposits, Marcin Karbownik
Journal of Sustainable Mining
Methane is one of the main greenhouse gases (GHG) affecting climate change, and proper quantification of the amount of its emissions to the atmosphere is crucial. The basic parameter for determining the potential amounts of naturally occurring methane in coal for both hard coal and lignite is the methane content. Determination of the methane content of lignite for open-pit mines is not commonly used and required as there is no possibility of its accumulation in the mine workings, as is the case for underground hard coal mines. In this article, two research areas for open-pit lignite mines were analyzed in …
Safety Distances For Fires In Underground Hard Rock Mines, Rickard Hansen
Safety Distances For Fires In Underground Hard Rock Mines, Rickard Hansen
Journal of Sustainable Mining
Preventing the ignition of combustibles in an underground mine will be one of the decisive actions affecting the risk to mining personnel during a fire. This study focuses on the application of safety distances in underground hard rock mines, where a safety distance will ensure that the incipient heat flux upon the fuel surface will not be sufficient for ignition. No earlier study has been conducted on safety distances in underground mines, and where data from earlier fire experiments and studies were applied. Safety distances were calculated using empirical expressions, accounting for influencing parameters. It was found that safety distances …
Relationship Between Continental Chemical Weathering Trends In The North China Basin And The High-Latitude Glacial Cycles From The Late Carboniferous To The Early Permian, Ling Ziyu, Yang Minfang, Wang Lei, Wang Ye, Zhang Peixin, Liu Haoqing, Shao Longyi, Lu Jing
Relationship Between Continental Chemical Weathering Trends In The North China Basin And The High-Latitude Glacial Cycles From The Late Carboniferous To The Early Permian, Ling Ziyu, Yang Minfang, Wang Lei, Wang Ye, Zhang Peixin, Liu Haoqing, Shao Longyi, Lu Jing
Coal Geology & Exploration
Objective and Methods The Late Paleozoic Ice Age (LPIA; ca. 360‒254 Ma), the only period recording the transition from icehouse to greenhouse conditions throughout the geological history, can provide a deep-time perspective for glacier-environment-climate coevolution and future climate change. To gain a deep understanding of the potential relationship between the continental chemical weathering trends in low-latitude regions and the glacial cycles in the high-latitude Gondwana region from the Late Carboniferous to the Early Permian, this study investigated the mudstones of the Benxi-Taiyuan formations, Liujiang coalfield, North China Basin. Using multiple chemical weathering indices such as chemical index of alteration (CIA), …
Anisotropy In Non-Darcy Flow In Individual Rough-Walled Rock Fractures, Zhu Yinbin, Liao Zhen, Li Changdong, Liu Hongbin, Jiang Xihui
Anisotropy In Non-Darcy Flow In Individual Rough-Walled Rock Fractures, Zhu Yinbin, Liao Zhen, Li Changdong, Liu Hongbin, Jiang Xihui
Coal Geology & Exploration
Objective Investigating the flow behavior of fluids in individual rough-walled rock fractures is fundamental for fully understanding the seepage characteristics of fluids in rock fracture networks. Methods Rock fractures were artificially synthesized based on the fractal theory, and numerical simulations of seepage along these fractures were performed using the COMSOL Multiphysics software. Then, fracture specimens with the same geometric characteristics as numerical models of fractures were prepared using 3D printing technology. In combination with the self-designed equipment for seepage experiments, this study conducted seepage experiments on these fracture specimens under different injection flow rates to investigate the impacts of varying …
Distributed Optical Fiber Acoustic Sensing-Based Optimization Of Microseismic Source Localization In The Hydraulic Fracturing For Coalbed Methane Production, Hua Hao, Cheng Bingjie, Xu Tianji, Yan Zhenqian, Gao Bo, He Cheng
Distributed Optical Fiber Acoustic Sensing-Based Optimization Of Microseismic Source Localization In The Hydraulic Fracturing For Coalbed Methane Production, Hua Hao, Cheng Bingjie, Xu Tianji, Yan Zhenqian, Gao Bo, He Cheng
Coal Geology & Exploration
Objective To achieve safe and efficient hydraulic fracturing, it is necessary to conduct timely and accurate microseismic monitoring in the reservoir stimulation process. The purpose is to analyze and assess the fracturing effects. Methods Using a permanently deployed fiber-optic cable outside the casing of a coalbed methane (CBM) well, this study employed distributed optical fiber acoustic sensing (DAS)for full-borehole, wide-azimuth, and high-density real-time monitoring of microseismic events induced by the hydraulic fracturing of coal seams. Furthermore, this study proposed a novel method for localizing microseismic sources based on information about wave travel time and a source-constrained mapping algorithm. First, effective …
A Model Predictive Control Method For Directional Borehole Trajectories In Underground Coal Mines, Li Hao, Yao Ningping, Lu Chengda, Zhang Jinbao, Wei Hongchao, Wu Jiajun, Li Jinyu
A Model Predictive Control Method For Directional Borehole Trajectories In Underground Coal Mines, Li Hao, Yao Ningping, Lu Chengda, Zhang Jinbao, Wei Hongchao, Wu Jiajun, Li Jinyu
Coal Geology & Exploration
Objective It is challenging to control the borehole trajectories during directional drilling in complex strata in underground coal mines, resulting in significant deviations from the designed trajectories. Given this, this study proposed a method for tracking and controlling directional borehole trajectories based on model predictive control (MPC). Methods Focusing on the directional drilling process conducted using a screw drill, this study investigated the movement patterns of the directional screw drill by analyzing the characteristics of directional drilling in complex strata in underground coal mines. Based on the kinematic theory, this study developed a borehole trajectory extension model for sliding directional …
Analyzing In-Situ Stress Response Characteristics Of Coals Based On Optimized Measurement-While-Drilling Parameters, Zhang Kun, Wang Ke, Ren Jianxi, Feng Shangxin, Chang Pengbo, Zhao Yutao, Miao Yanping, Hu Jian
Analyzing In-Situ Stress Response Characteristics Of Coals Based On Optimized Measurement-While-Drilling Parameters, Zhang Kun, Wang Ke, Ren Jianxi, Feng Shangxin, Chang Pengbo, Zhao Yutao, Miao Yanping, Hu Jian
Coal Geology & Exploration
Background The spatial distribution of stress in coals in underground coal mines is a significant factor influencing the safe production of mines and the optimization of mining processes. The quantitative, advanced prediction of in-situ stress in coals is significant for the precise regulation of the underground stress field and the classification of areas with rock burst risks. Methods Using the self-developed monitoring-while-drilling system, this study conducted indoor coal drilling experiments under different drilling conditions and explored the laws of effects of drilling conditions on drilling parameters (e.g., torque and drilling displacement) under varying stresses. Furthermore, this study developed a method …
Design And Simulations Of A Balancing Device With A Hydraulic Circuit For A Fully Hydraulic Top Drive Drilling System For A Drilling Rig Capable Of 10 000-M-Deep Drilling, Luo Chaochun, Wang Qingyan, Fan Liming, Li Haoxuan, Zhong Weiling, Guo Naiming
Design And Simulations Of A Balancing Device With A Hydraulic Circuit For A Fully Hydraulic Top Drive Drilling System For A Drilling Rig Capable Of 10 000-M-Deep Drilling, Luo Chaochun, Wang Qingyan, Fan Liming, Li Haoxuan, Zhong Weiling, Guo Naiming
Coal Geology & Exploration
Objective The balancing device for a fully hydraulic top drive drilling system (TDDS), an important part of a drilling rig capable of 10000-m-deep drilling, is designed to dynamically and accurately regulate the axial load in the screwing and unscrewing processes. This helps protect the threads of drill rod connectors from damage, thereby ensuring the stability and safety of drilling operations. Methods This study designed a balancing device with a hydraulic circuit for the SP.TD-01A fully hydraulic TDDS, aiming to achieve the balancing and bouncing functions required during the application of the TDDS. First, this study determined the structure and principal …
Table Of Contents, The Editors
Sedimentary Characteristics Of Coals In Meandering River And Braided River Facies And During Their Transitions: A Case Study The Walloon Subgroup In The F8 Block In The Surat Basin, Australia, Cui Zehong, Zhao Yibo, Li Zhihua, Li Shengli, Li Weiru
Sedimentary Characteristics Of Coals In Meandering River And Braided River Facies And During Their Transitions: A Case Study The Walloon Subgroup In The F8 Block In The Surat Basin, Australia, Cui Zehong, Zhao Yibo, Li Zhihua, Li Shengli, Li Weiru
Coal Geology & Exploration
Objective Australia is recognized as the fourth largest producer and the second largest exporter of coals in the world. The Bowen-Surat Basin is the largest coal producing basin in this country. The Surat Basin exhibits coal-bearing layers of the Middle Jurassic Walloon Subgroup. This subgroup features a sedimentary environment of fluvial facies, necessitating clarifying the differential sedimentary characteristics and patterns of coal seams in braided river and meandering river facies and during their transitions. Methods Using comprehensive geological analysis methods, as well as seismic data, logs, and core data, this study established the sedimentary pattern of the study area. Using …
Geological-Engineering Integrated Reconnaissance Survey Technology For Skylights As A Hidden Disaster-Causing Factor, Dong Mintao
Geological-Engineering Integrated Reconnaissance Survey Technology For Skylights As A Hidden Disaster-Causing Factor, Dong Mintao
Coal Geology & Exploration
Objective Skylights represent a primary hidden disaster factor in mines in the southern Yushen mining area within the Shanbei Jurassic coalfield, Shaanxi Province. Since they are hidden and difficult to detect, their distribution in the mining area remains unclear, posing pronounced safety hazards. This necessitates developing effective technical means to overcome challenges in the spatial exploration of skylights and ensure mine safety. Methods Focusing on a typical mine in the Yushen mining area as an example, this study explored the spatial distribution characteristics and types of skylights in the study area using the geological-engineering integrated reconnaissance survey technology that combines …