Test On The Strength Of The Backfill Fine Sand Mixture Composed Of Cement-Fly Ash-Cinder,
2019
School of Earth Science and Engineering, Nanjing University, Nanjing 210023, China
Test On The Strength Of The Backfill Fine Sand Mixture Composed Of Cement-Fly Ash-Cinder, Wen Liang, Yan Changhong, Zhang Zheng, Xu Baotian, Zhang Shunjing, Zhang Dongping, Zhou Yinkang
Coal Geology & Exploration
By using orthogonal test to analyze the influence of cement content, fly ash content and cinder content, the non-confining compression strength test was carried out for the stability of large-scale landfill base structure and for the saving costs. The strength at different curing ages was analyzed by variance, and the reinforcement mechanism was also studied. The test results showed that the optimal ratio of cement stabilized soil under different factors is 20% of cement, 15% of fly ash, 10% of cinder, and the strength is the largest at this point. And the influence of cement content on the strength of …
Acoustic Emission Test Of Calcareous Sands Under Undrained Condition,
2019
School of Civil Engineering and Architecture, Wuyi University, Jiangmen 529020, China; Hunan Provincal Key Laboratory of Shale Gas Resource Utilization, Hunan University of Science and Technology, Xiangtan 411201, China
Acoustic Emission Test Of Calcareous Sands Under Undrained Condition, Yang Chao, Wang Kai, Qiao Liping, Meng Qingshan, Wang Ren
Coal Geology & Exploration
Calcareous sand acoustic emission was tested under undrained condition to study the law of acoustic emission with different confining pressure, shear rate, initial void ratio and grading. The results showed that when the confining pressure was lower than 400 kPa, calcareous sand acoustic emission event rate increased with confining pressure. But when the confining pressure was increased to 800 kPa, calcareous sand acoustic emission event rate decreased. The test of calcareous sand was divided into particle breakage stage and particle slip stage in low shear rate. Two stages can't be distinguished clearly as the shear rate increases. Loose and dense …
Random Noise Attenuation By Eemd In Common Offset Gathers,
2019
The Engineering Technical College of Chengdu University of Technology, Leshan 614000, China; College of Geophysics, Chengdu University of Technology, Chengdu 610059, China
Random Noise Attenuation By Eemd In Common Offset Gathers, Shi Zhanzhan, Xia Yanqing, Zhou Huailai, Chi Yuelong, Pang Su
Coal Geology & Exploration
There are two problems in the random noise attenuation in f-x domain:(1) Reflected waves as hyperbolic events in pre-stack CMP gather or shot gathers, de-noising will damage the effective wave; (2) Seismic signals are complex non-stationary signals, requiring that the de-noising method has the adaptivity. Aiming at these two problems, a random noise suppression method based on f-x EEMD was proposed. The method utilizes the reflected waves which are horizontal events in common offset gathers, satisfying the f-x domain de-noising assumption, and the good adaptability of EEMD algorithm to non-stationary signals. For each frequency …
Analysis On Influence Of Ground Transmitting Electrode On Bidirectional Em-Mwd Signal Transmission Based On Ansys,
2019
Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China
Analysis On Influence Of Ground Transmitting Electrode On Bidirectional Em-Mwd Signal Transmission Based On Ansys, Shao Chun, Han Jian, Chu Zhiwei, Xu Lin
Coal Geology & Exploration
The grounded emitter electrode is a necessary component of the bidirectional EM-MWD signal downlink system, and its reasonable parameter setting can improve the signal downlink effect, but at present, little is known about its influence on the downlink signal. This paper is based on the bi-directional EM-MWD working mechanism, combined with the current field theory, using ANSYS finite element software, establishes a three-dimensional simulation model of bidirectional EM-MWD signals, and analyzes the emission distance, length, diameter and resistivity of the ground transmitting electrode versus the downlink signal. The simulation results show that the downlink signal reception effect is positively correlated …
Elastic Wave Prestack Reverse Time Migration On Undulating Surfac,
2019
School of Geosciences and Technology, Southwest Petroleum University, Chengdu 610500, China
Elastic Wave Prestack Reverse Time Migration On Undulating Surfac, Liu Yang, Zhao Hu, Yin Cheng, Wu Sihai, Dai Ronghuo, Di Zhixin
Coal Geology & Exploration
At present, seismic exploration is facing many challenges in the "double complex" area, especially the undulating surface make it difficult to accurately image the underground complex structures. In this paper, we have studied the elastic wave prestack reverse time migration method for undulating surface, and a simple and effective treatment method was adopted to solve the free boundary conditions of undulating surface. In addition, the storage strategy of the effective boundary was used to solve the problem of big storage of elastic wave prestack reverse time migration. The numerical experimental results also show that this method can accurately reconstruct the …
Influence Mechanism Of Hard Brittle Abrasive On The Drilling Performance Of Impregnated Diamond Bit,
2019
National Local Joint Engineering Laboratory of Marine Mineral Resources Exploration Equipment and Safety Technology, Hunan University of Science and Technology, Xiangtan 411201, China
Influence Mechanism Of Hard Brittle Abrasive On The Drilling Performance Of Impregnated Diamond Bit, Wang Jialiang, Wei Wenjie, Zhang Shaohe, Peng Fenfei
Coal Geology & Exploration
In order to improve the performance of diamond bit, impregnated diamond bit was prepared by adding different mass of hard brittle abrasive into matrix and drilling performance was tested by drilling experiments. The effect of hard brittle abrasive on drilling performance was studied. The results show that adding 5.5% SiC particle had better effect and the drilling efficiency increased by 55.14% compare with common bit. The hard brittle abrasive in the matrix can improving the microstructure of bit. The hard brittle abrasive left in the down hole can improve the erosion performance of washing fluid to matrix and increase the …
Finite Element 2d Forward Modeling Of Dc Method With Line Source,
2019
College of Geology and Environment, Xian University of Science and Technology, Xian 710054, China
Finite Element 2d Forward Modeling Of Dc Method With Line Source, Xie Haijun, Li Zhiqiang, Li Sheng
Coal Geology & Exploration
In direct current prospecting, the forward calculation of 3D point source is complex and the calculation quantity is large, and using the Fourier transform can converted into 2D point source, but it is more complicated than that of 2D line source. This paper is based on Matlab programming, using the first boundary condition, and gives numerical solution of two-dimensional finite element of DC method with line source, through comparing with theoretical value of homogeneous half-space, the correctness of calculation results was verified. Then the high and low resistivity geoelectric models were built, the response of single side power supply and …
The Research Progress And Work Prospect Of Special Purpose Coal,
2019
School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China; Aero Photogrammetry & Remote Sensing Bureau, China National Administration of Coal Geology, Xian 710199, China
The Research Progress And Work Prospect Of Special Purpose Coal, Qiao Junwei, Ning Shuzheng, Qin Yunhu, Zhang Ning, Li Congcong, Zhang Jianqiang, Wei Yingchun, Zhu Shifei, Zhu Kaijia
Coal Geology & Exploration
Based on the refined geological exploration of coal, the clean and efficient use of coal, this paper reviews the implications of scarce coal and special purpose coal in previous studies. It was pointed out that special purpose coal is based on clean and efficient use of coal for coal resources with special industrial applications. The main types of coal are liquefaction coal, gasification purpose coal, coking coal and special high-element coal. Based on the coal quality evaluation of coal and the use of coal graded quality, this paper has sorted out the key evaluation indicators and evaluation parameters of special …
Technology And Practice For Deep Cbm Fracturing In Eastern Ordos Basin,
2019
Oilfield Production Optimization Institution, China Oilfield Services Limited, Tianjin 300450, China
Technology And Practice For Deep Cbm Fracturing In Eastern Ordos Basin, Wang Xuxing, Wang Xingzun, Guo Bumin, Yuan Zheng, Feng Qing
Coal Geology & Exploration
The resources of deep coalbed methane buried at depth of more than 1 200 m in the eastern Ordos basin are rich and the key point for further exploration and development of CBM in the future. Compared with shallow CBM fracturing, there are many challenges in deep CBM fracturing such as with high situ stress, high closure stress, breakdown pressure as well as complex mechanical parameters of rock. Combined with the existing practice of CBM fracturing, taking the deep CBM buried at depth of about 2 000 m in the eastern Ordos basin as an example, tubing+ circulating SSD +packer …
Application Of Improved Hierarchic Analytic Process In The Classification Of Mine Hydrogeological Types,
2019
China Coal Research Institute, Beijing 100013, China; Xian Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xian 710077, China; Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard, Xian 710077, China
Application Of Improved Hierarchic Analytic Process In The Classification Of Mine Hydrogeological Types, Wang Tiantian, Jin Dewu, Yang Jian, Liang Xiangyang
Coal Geology & Exploration
The classification of mine hydrogeological type is an important part of mine hydrogeology work. It is of great significance to analyze water filling conditions, evaluate water hazard and guide mine water prevention work. In order to evaluate mine hydrogeological conditions, this paper introduced optimal transfer matrix to improve hierarchic analytic process, and then applied this method to classify mine hydrogeological types. Taking four pairs of active mines in Hujierte mining area of Inner Mongolia as an example, the evaluation index system for classification of mine hydrogeological types was built on the basis of analysis of the hydrogeological conditions, then theoretical …
Design And Application Of Drilling Rod Vibration Frequency Measurement System,
2019
Faculty of Engineering, China University of Geosciences, Wuhan 430074, China
Design And Application Of Drilling Rod Vibration Frequency Measurement System, Liu Naipeng, Hu Yule, Wang Wei
Coal Geology & Exploration
During drilling, resonance is generated when the natural frequency of the drilling rod is consistent with the external excitation frequency. This will cause fatigue-failure of the drilling rod and serious consequences. To avoid this, a drilling rod vibration measurement system based on Micro-Electro-Mechanical System was designed. This system uses the three-axis acceleration sensor to measure the acceleration of the drilling rod in three directions. The upper computer software written in LabVIEW can storage, upload, display and process data. Then the fast Fourier Transform was taken to analyze the vibration frequency of the drilling rod. Finally the system is installed on …
Elastic Mechanics Solution Of Water Proof Key Layer In Coal Seam Floor Under High Water Pressure,
2019
School of Earth and Environment, Anhui University of Science Technology, Huainan 232001, China
Elastic Mechanics Solution Of Water Proof Key Layer In Coal Seam Floor Under High Water Pressure, Wang Yan, Yao Duoxi, Lu Haifeng
Coal Geology & Exploration
Aiming at the problem of water resisting capacity of the key layer in seam floor under the action of high pressure water, the key stratum was simplified as a fixed beam. The stress and displacement were calculated by the stress function method and the semi inverse method respectively. The results of two calculations were compared with the FLAC3D results. The results show that the stress and displacement obtained by the stress function method are more appropriate than those calculated by the FLAC3D method. It is suggested that for elastic mechanics analytic method of the fixed beam of the …
Integrated Identification Of Sequence Boundary Through Outcrop, Seismic With Logging And Geochemistry: A Case Of Jurassic In Northeastern Margin Of Ordos Basin,
2019
Tianjin Center, China Geological Survey, Tianjin 300170, China
Integrated Identification Of Sequence Boundary Through Outcrop, Seismic With Logging And Geochemistry: A Case Of Jurassic In Northeastern Margin Of Ordos Basin, Zhang Tianfu, Zhang Yun, Cheng Yinhang, Miao Peisen, Ao Cong, Jin Ruoshi, Duan Lianfeng, Duan Xiaolong
Coal Geology & Exploration
Jurassic strata is mainly rock series containing coal and uranium in Ordos basin. The recognition of Jurassic sequence interfaces were mainly relied on the field outcrop, logging lithology of unconformity surface or the sedimentary discontinuity. However, it is tend to experience human recognition of randomness in the sequence interfaces recognition without macroscopic characteristics. Therefore, based on routine identification work such as outcrop profile and electrical curve of nearly 1 000 boreholes, combined with vertical changes of two-dimensional seismic profile and chemical index of alteration(CIA), three long-term cycle sequence interfaces(TSB1-TSB3) and seven medium-term cycle sequence interfaces(SB1-SB7) were finally identified in Jurassic …
Response Relation Between Fracturing Curve And Reservoir Pollution Degree Of Coalbed Methane Wells,
2019
School of Geoscience and Surveying Engineering, China University of Mining and Technology(Beijing), Beijing 100083, China
Response Relation Between Fracturing Curve And Reservoir Pollution Degree Of Coalbed Methane Wells, Zhuang Dengdeng, Wang Yanbin, Tao Chuanqi, Chen Yan
Coal Geology & Exploration
In order to study the relationship between response curve and the pollution degree of fractured reservoir, taking Shizhuang block in Qinshui basin as an example, wells with different sensitivity of reservoir in the block were selected, through comparison of the difference of the dropping trace characteristics after the hydraulic curve reaches the fracture pressure in the fracturing curves of fracturing operation in different wells, the response law of hydraulic dropping trace and the reservoir sensitivity was summed up. Then in the same block according to the dropping trace of the hydraulic curves, the sensibility of reservoir was judged in several …
Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects,
2019
Università degli Studi di Milano-Bicocca
Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Zurab Gogoladze
Department of Geological and Mining Engineering and Sciences Publications
The Enguri dam and water reservoir, nested in the southwestern Caucasus (Republic of Georgia), are surrounded by steep mountain slopes. At a distance of 2.5 km from the dam, a mountain ridge along the reservoir is affected by active deformations with a double vergence. The western slope, directly facing the reservoir, has deformations that affect a subaerial area of 1.2 km2. The head scarp affects the Jvari–Khaishi–Mestia main road with offsets of man-made features that indicate slip rates of 2–9 cm yr−1. Static, pseudostatic and Newmark analyses, based on field and seismological data, suggest different unstable …
Feed Control: Composite Recycle,
2019
Central Washington University
Feed Control: Composite Recycle, Rosy Perez
All Undergraduate Projects
The Boeing Company gave Central Washington University an opportunity for students to research and come up with an idea to reduce costs and landfill waste caused by the trimmings from the 777x composite wing pieces. The engineering and manufacturing for this project is about transporting composite material through to the delamination and chipper process. The delamination process uses a ram to press two claw shaped devices together that bends and deforms the material in opposite directions. The chipper process uses counter rotating saw blades spaced 1/8” apart to produce small shredded material. It is important for this newly designed feed …
The Dark Side Of Servant Leadership,
2019
Montana Tech
The Dark Side Of Servant Leadership, Thomas W. Camm
Mining Engineering
No abstract provided.
Vertical Stress And Deformation Characteristics Of Roadside Backfilling Body In Gob-Side Entry For Thick Coal Seams With Different Pre-Split Angles,
2019
Taiyuan University of Technology, Shanxi Province Research Center of Green Mining Engineering Technology
Vertical Stress And Deformation Characteristics Of Roadside Backfilling Body In Gob-Side Entry For Thick Coal Seams With Different Pre-Split Angles, Yuqi Ren, Guorui Feng, Pengfei Wang, Jun Guo, Yi Luo, Ruipeng Qian, Qiang Sun, Songyu Li, Yonggan Yan
Faculty & Staff Scholarship
Retained gob-side entry (RGE) is a significant improvement for fully-mechanized longwall mining. The environment of surrounding rock directly affects its stability. Roadside backfilling body (RBB), a man-made structure in RGE plays the most important role in successful application of the technology. In the field, however, the vertical deformation of RBB is large during the panel extraction, which leads to malfunction of the RGE. In order to solve the problem, roof pre-split is employed. According to geological conditions as well as the physical modeling of roof behavior and deformation of surrounding rock, the support resistance of RBB is calculated. The environment …
Coupling Simulation Model Between Mine Ventilation Network And Gob Flow Field,
2019
Xi'an University of Science and Technology
Coupling Simulation Model Between Mine Ventilation Network And Gob Flow Field, F.I. Wu, Y. Luo, X-T Chang
Faculty & Staff Scholarship
Many numerical simulation studies of coal spontaneous combustion have focused on the leakage flow field in the mine gob. However, most of these studies isolate the gob from the mine ventilation system, failing to consider the effects of air leakage on gob boundary conditions. A novel model coupling the mine ventilation network (MVN) and gob flow field (GFF) has been developed to simulate the overall mine ventilation system. The concept of network boundary node was proposed and the corresponding air flow rate balance equations were developed based on the node pressure method for MVN calculation and the finite element method …
Leaching Characteristics Of Rare Earth Elements From Bituminous Coal-Based Sources,
2019
University of Kentucky
Leaching Characteristics Of Rare Earth Elements From Bituminous Coal-Based Sources, Xinbo Yang
Theses and Dissertations--Mining Engineering
The demand for rare earth elements (REEs) has increased over the last decade due to applications in high technology devices including those in the defense industry. The recovery of REEs from primary sources such as rare earth minerals are viable using physical separations followed by chemical processing. However, weak market values and environmental concerns have limited the viability of such operations. On the other hand, REE recovery from secondary sources such as apatite ore, bauxite waste, and waste recycling, provides an opportunity to take advantage of a resource that does not require mining costs as well as other associated costs …
