rock in coal mine
- صفحه اصلی
- rock in coal mine
Rock fall. The NIOSH Mining Program is working to combine empirical, laboratory, and numerical studies to advance the state-of-the-art methods for protecting mine workers from all forms of rock fall. Major …
به خواندن ادامه دهید
Coal mine water inrush threatens mining operations, pollutes the environment, and wastes significant water resources [17], [18]. The Yanzhou mining area is a typical North China-Type coalfield. ... Experimental investigation on mining-induced strain and failure characteristics of rock masses of mine floor. Geomat Nat Haz Risk, 11 (1) …
به خواندن ادامه دهید
In this study, the water–rock interaction between fracture water, mine water, deionized water, and two types of roof collapse rocks (fine sandstone and mudstone) in …
به خواندن ادامه دهید
2.1 Sample Preparation. Wulong Colliery, comprising minable coal seams found in the third member of the Shahai and Fuxin formations of the Cretaceous Period, numbering 10 coal-seam formations in total, is located in the middle of Fuxin Coalfield, Liaoning Province, China, covering an area of 11.76 km 2, and has a monoclinic …
به خواندن ادامه دهید
In coal mines, underground roadways are required to transport coal and personnel. Such tunnels can become unstable and hazardous. This study simulates deformation and damage in the rock …
به خواندن ادامه دهید
3. Numerical Calculation Model and Results 3.1. Numerical Calculation Model and Its Parameters. According to the comprehensive histogram of 9103 working face in Junde Coal Mine, the initial three-dimensional numerical model is established with the help of 3DEC numerical simulation analysis software, as shown in Figure 4.The model is …
به خواندن ادامه دهید
reservoir capacity and the coordinated development of coal mining and water resources protection in western China. Furthermore, they provide a scientific basis for both basic theoretical research and practical applications in particle packing systems. These systems encompass various materials such as caved ore and rock in metal mines, …
به خواندن ادامه دهید
The fracture development of the overlying strata after coal mining is an important guarantee of efficient gas drainage. In order to explore the fracture evolution characteristics close to a mined coal seam group, the F 15.16 −24130 working face in the Pingdingshan No. 10 coal mine was taken as the research background. The FLAC3D …
به خواندن ادامه دهید
A borehole deformation sensor for long-term stress monitoring in coal mine rock based on optical fiber Bragg gratings (FBGs) is presented. The sensor converts borehole deformation into optical fiber strain by using four rings. For each ring, two FBGs are bonded with the ring to measure the borehole deformation, and a reference FBG free …
به خواندن ادامه دهید
Dynamic early-warning of rock burst in coal mine by low-frequency EMR. Before the rock burst, since there are micro-fractures and crack propagation in the coal, local coal rock fractures emerge continually, and this process has induced a lot of low …
به خواندن ادامه دهید
As coal mining progresses to greater depths, the rate and severity of coal burst hazards have greatly increased, resulting in significant operational and safety challenges. Appropriate rock support design for coal burst-prone roadways requires the understanding of the mechanical characteristics of the support system under impact …
به خواندن ادامه دهید
In China (the largest coal producer), a dramatic increase in the number of coal mines reporting rock burst hazards has been observed from 32 in 1985 to more than 253 by the end of 2019. Therefore, understanding the mechanism of rock bursts and their monitoring strategies is a very challenging topic to improve mining safety and productivity.
به خواندن ادامه دهید
Water inrush in underground mines is a major safety threat for mining personnel, and it can also cause major damage to mining equipment and result in severe production losses. Water inrush can be attributed to the coalescence of rock fractures and the formation of water channel in rock mass due to the interaction of fractures, hydraulic …
به خواندن ادامه دهید
2.2 Specimen preparation and experimental methods. The sample is made of large coal and roof rock obtained from the coal mine. By coring and grinding, coal and rock are made into cylindrical specimens with a size of ϕ 50 mm × 100 mm. The specimens were flat at both ends, and the specimens that did not meet the dimensional …
به خواندن ادامه دهید
Cutting rock slows mining machines and hurts production. And rock has to be removed from coal before it can be sold. So NPR and FRONTLINE wanted to know why mining companies didn't act on their ...
به خواندن ادامه دهید
Coal is a black or brownish-black sedimentary rock that can be burned for fuel and used to generate electricity. It is composed mostly of carbon and hydrocarbons, which contain energy that can be released through combustion (burning). Coal is the largest source of energy for generating electricity in the world, and the most abundant fossil fuel ...
به خواندن ادامه دهید
During the storage of underground water reservoirs in coal mines, water–rock interaction occurred between mine water and collapsed rocks, resulting in improved mine water quality, but the water–rock process and mechanism have not been clarified. In this study, six sets of simulated experiments were designed to investigate the …
به خواندن ادامه دهید
Coal mine waste rock (CMWR) generated in coal mining activities is one of the most significant sources of industrial solid waste. Nearly 4.5 billion tons of CMWR stockpiled in …
به خواندن ادامه دهید
Mine fires are a serious natural disaster that can occur during coal mine operation. They have a great impact on coal resources, the environment, and the health of workers (Roy et al. 2019; Liu and Zhou 2010; Song and Kuenzer 2014; Chen et al. 2012; Liu et al. 2022; Qin et al. 2022; Liu et al. 2019; Peng et al. 2022; Nie et al. 2021).Coal …
به خواندن ادامه دهید
The research related to WRI in underground coal mining mainly focuses on the water inrush form roof and floor, water weakening of roadway surrounding rock (coal …
به خواندن ادامه دهید
Go to: Abstract. The identification and mitigation of adverse geologic conditions are critical to the safety and productivity of underground coal mining operations. To anticipate and …
به خواندن ادامه دهید
of the roof rock, (2) the excavation geometry, and (3) the forces applied to the mine roof. ROCK STRENGTH Rock strength traditionally is estimated from laboratory tests. The uniaxial compressive test is the most commonly used. Figure 1 shows the approximate range of compressive strengths observed in U.S. coal measure rock. Triaxial tests,
به خواندن ادامه دهید
Rock burst is one of the main coal and rock dynamic disasters that affect coal mine production. This kind of burst disaster refers to the sudden, sharp and violent …
به خواندن ادامه دهید
This study focuses on the occurrence mechanism and monitoring and early warning technology for rockburst in coal mines. Results showed that the prevention and control of rockburst had made significant progress. However, with the increasing mining depth, several unresolved concerns remain challenging.
به خواندن ادامه دهید
With coal mining in the second area, under the tectonic stress field, the coal and rock mass stress and energy are in dynamic balance, and energy accumulates locally in the coal and rock mass.
به خواندن ادامه دهید
Coal mines' failures are affected by various factors such as geological and structural parameters (Singh 2005).Thickness, number, depth, and dip angles of seams; …
به خواندن ادامه دهید
Glossary of Mining Terminology. A. Abutment - In coal mining, (1) the weight of the rocks above a narrow roadway is transferred to the solid coal along the sides, which act as abutments of the arch of strata spanning the roadway; and (2) the weight of the rocks over a longwall face is transferred to the front abutment, that is, the solid coal ...
به خواندن ادامه دهید
The surrounding rock stability classification of coal roadway is supposed to be based on the characteristics of sedimentary rock (and local igneous rock) in coal mine, which requires clear physical meaning of evaluation index, easy access to parameters, simple classification method, and strong practicability.
به خواندن ادامه دهید
The stability monitoring of surrounding rock in layered roadway is an important method to ensure the safety of deep mining coal mine. In view of the actual situation of roadway stability monitoring, based on similarity theory, the deep roadway model is built and small-sized ordinary bolts and constant resistance and large deformation …
به خواندن ادامه دهید
Coal mining - Underground mining: In underground coal mining, the working environment is completely enclosed by the geologic medium, which consists of the coal seam and the overlying and underlying strata. ... The science of rock mechanics is well advanced and is useful for understanding such stability problems and for the design of …
به خواندن ادامه دهید
Burst induction mechanism of rock-coal-bolt (RCB) system. The stress of the roadway surrounding rock is redistributed with thin coal seam mining, forming a stress-enhancing zone from inside to ...
به خواندن ادامه دهیدSuper high coal seams used to be mined by protecting the roadway with wide pillar normally 20 ~ 30 m in width. As mining depth and intensity increase, some mines chose to retain 40 ~ 60-m wide pillar for roadway protection, causing tremendous waste of coal resources (Ghasemi et al. 2014; Cao and Zhou 2021; Wang et al. 2020).In …
به خواندن ادامه دهید
According to the analysis of structural characteristics of the cover rock in Xiaoyun Coal Mine, because the cover rock of Coal Seam 3 1318 working face was mostly composite rock structure, the ...
به خواندن ادامه دهید
A camera, rock hammer, measuring tape, and a focus on changing conditions can provide a wealth of valuable data to enhance safety by revealing trends that can be linked to geological hazards. ... The roof and floor lithology should be examined because the roof and floor are critical coal mine structural members and this can help detect weak ...
به خواندن ادامه دهید
Weak, layered, and fragile rock mass formation, if not supported properly, is subject to roof failure thereby affecting safety and productivity in underground coal mines. Though Central Mining Research Institute – Indian School of Mines Rock Mass Rating (CMRI-ISM RMR) based well-defined support design guidelines are established, still …
به خواندن ادامه دهید
The surrounding rock of a coal mine roof fractures with the excavation of the underground working face in coal mining. These mining-induced fractures are connected and extended upward to form water inrush channels. A water inrush accident may occur when there is a sufficiently large water source. To elucidate the formation mechanisms of …
به خواندن ادامه دهید
NIOSH is actively investigating how to protect mine workers from rock falls in ribs of coal mines and apply numerical modeling tools to design support that will reduce large falls of roof. NIOSH Mining's comprehensive approach to ground control looks at global stability which can be maintained with good pillar design, local stability which ...
به خواندن ادامه دهید
coal mining, extraction of coal deposits from the surface of Earth and from underground. Mongolia: coal mine. Coal is the most abundant fossil fuel on Earth. Its predominant use has always been for …
به خواندن ادامه دهیدچه بخواهید با ما کار کنید و چه علاقه مند به کسب اطلاعات بیشتر در مورد محصولات ما هستید، مایلیم از شما بشنویم.