Abstract Many recent examples have shown that rockfalls can occur in underground steep coal mines. The stratigraphic circumstances, block formation mechanism, and cumulative damage effects of rockfalls in the longwalls of a steeply dipping coal seam (SDCS) make them detrimental to workplace safety. Therefore, this study …
Recently, while automatic mining technology is increasingly applied in China for thin seams, the corresponding automatic cutting technol-ogy has made new advances. …
Jiang et al. (2015) simulated the law of mining stress evolution, coal seam roof motion and fault activation under the thick-hard strata by 3-D numerical calculation method.
et al. 2016; Zheng et al. 2017). A majority of coal seams in Guizhou Province show characteristics including strata gently dipping into slopes, low seam thickness, and many mineable coal seams (Zhao et al. 2016). Slope deformation induced by coal mining is manifest as surface subsidence and sliding of the front of the slope, showing a high risk ...
Highwall mining combines the advantages of open-cut and underground approaches, and allows soft and thick coal seams to be mined at the rear of the coal rib at the …
DOI: 10.3389/fenrg.2024.1333016 Corpus ID: 267113216; Research and application of 'three zones' range within overlying strata in goaf of steep coal seam @article{Yang2024ResearchAA, title={Research and application of 'three zones' range within overlying strata in goaf of steep coal seam}, author={Shouguo Yang and Ning Xu …
Western China has a larger proportion of near-vertical (the seam inclination is greater than 45 • in China) and extremely thick coal seams (the thickness of coal seams is greater than 8 m in ...
Major rockslide is the main type of geological hazards in the mining mountainous areas of southwestern China. The failure modes and behaviors of this kind of rockslides are complex. Taking the Jiguanling landslide as an example, centrifuge modelling was taken to analyze the failure mechanism of a steep-dip carbonate slope which was induced by …
There is, so far, no consensus achieved as to the definition of a steep coal seam. It is generally accepted that seams with dips of 35–55° [1], [2], [3] are defined as steep coal seams. The coal seams with a dip angle larger than 35° account for 17% of the coal reserves in China.
Underground extraction of thick coal seams in United States of America is not much visible in literature. However, application of hydraulic mining for thick coal seams in New Zealand has shown good results [7], [36] but for a scanty band width of the geo-mining conditions. This approach offered considerable financial benefits, but has limited ...
A subsidence control method by inversely-inclined slicing and upward mining SCISUM is proposed for ultra-thick steep seam to change and control of strata …
Steep coal seam mining activities will frequently occur during the next few decades in China. In this study, both experimental and numerical methods are …
The implementation of appropriate mining technologies is crucial for designing and planning the mining face related to steep coal seams and can …
The steep inclined seam is a difficult mining seam with a poor safety condition,a poor support stability,a lower mechanization and lower mining rate.According to those features of the thin and medium steep inclined seams,the paper proposed the improved direction and optimized method for the mining method of the thin and medium steep inclined …
In strip mining, also known as open cast mining, first top soil and rock overburden strata are removed to expose coal seams. Then the coal is excavated. Finally, the excavated area is reclaimed by backfilling, regrading, and planting vegetation (Pennsylvania Department of Environmental Protection, 2022).
Trans. Nonferrous Met. Soc. China 21(2011) s556-s561 Numerical simulation analysis of covering rock strata as mining steep-inclined coal seam under fault movement MA Feng-hai, SUN Li, LI Dun College of Civil and Architectural Engineering, Dalian University, Dalian 116622, China Received 19 June 2011; accepted 10 …
Using the discrete element numeric simulation program UDEC,the evolution law of mining-induced fractures in the mining process in steep coal seam was studied. Combined with the study of similar material simulation experi- ment results,the result by numerical calculation was verified. The results indicate that bed separation fissures are the main …
Techniques for Mining Coal from Coal Seams. Mining coal from coal seams is divided into two techniques: surface or opencast mining and underground mining. Surface or Opencast Mining. …
The current trend in coal production in India shows that underground mining contributed less than 5–8% of the total coal produced. On the other side, the contribution of opencast mining to coal ...
The key technologies for mining steep coal seams include global and regional strata control methods in the longwall face; methods for the longwall face machines to sustain …
The steep-inclined coal seams are widely distributed in western and southern China.These coal seams are complex and difficult for fully-mechanized coal mining.Therefore, developing a novel fluidized and intelligent mining method to recovery the steep-inclined coal seam is of great significance to ensure the safety production of coal.This paper …
1. Introduction. Coal seams exhibiting an inclination angle surpassing 45° are commonly referred to as steep coal seams. 1 Although these coal seams are ample and account for roughly 17% of the total coal reserves in China, 2 their yearly output represents a relatively meager fraction of the national total coal production, estimated to be …
Coal seams exhibiting an inclination angle surpassing 45° are commonly referred to as steep coal seams. Although these coal seams are ample and account for roughly 17% of the total coal reserves in China, their yearly output represents a relatively meager fraction of the national total coal production, estimated to be between 8 and …
Ultra-thick steep coal seam mining will inevitably lead to the increase of greater and violent ground subsidence and deformation. A subsidence control method by inversely-inclined slicing and upward mining is proposed in this paper. ... In China a prediction method named Probability Integration Method (PIF) was established by Liu …
coal technology, the production from opencast mining andis dominating underground mining for 5 decades, aroundand is being continued (R Singh, 2001). Thick seams of shallow cover depth can be extracted with open cast mining, whereas, deeper coal seams are more expensive to 1.extract and not viable (Rakesh et al., 2015).
OBJECTIVES—To answer the question whether living near opencast coal mining sites affects acute and chronic respiratory health. METHODS—All 4860 children aged 1-11 from five socioeconomically matched pairs of communities close to active opencast sites and control sites away from them were selected.Exposure was assessed by concentrations …
It aims to provide theoretical guidance for the efficient extraction of fractured gas from the coal seam roof in China. Section snippets ... In order to extract gas in the fracture zone of the coal seam roof, extraction methods are chosen based on the understanding of fracture distribution evolution and gas migration enrichment. The …
ABSTRACT With the increasing mining depth of coal mines, geologic hazards have become the main source of accidents. For this reason, coal seam prediction requires more assessment parameters, such as the degree of anisotropy, value, and elastic modulus. These parameters are difficult to determine using only the PP-wave. We have inverted …
This paper investigated the current status of TCS mining in China, and compared different approaches to feasibly recovery this resource. The surface miner …
Hydraulic support instability (HSI) is one of the most common causes of disasters in underground coal mining, posing a threat to the safety of mine workers and normal operation of the equipment. It is prone to occur in fully-mechanized mining faces with a large mining height (FMMLMH), especially when the dip angle of the coal seam …
Coal seam that is thinner than a certain value is defined as thin coal seams (TCS). It commonly occurs in China as it covers 84.2% of the mining area. This situation is even severe in China's large surface coal mines, in which TCS accounts for 10–50% of the total reserve. Most TCS cannot be feasibly mined due to the working conditions of …
1. Introduction. Deep coalbed methane (CBM) resources are abundant globally, with >50% of the in-place CBM resources found in coals at depths below 1524 m (5,000 ft), as indicated by the review of major coal-bearing basins worldwide (Kuuskraa and Wyman, 1993).For instance, over 70% of the gas in-place in the Piceance Basin of the …
few studies on the gas seepage characteristics of bottom coal in the horizontal slicing mining face of steeply inclined and extra-thick coal seams under true triaxial stress conditions. Therefore, the bottom coal of the horizontal slicing mining face on the east side of the no. 45 coal seam at +575 m level in
Abundant and widely distributed in China, steeply inclined coal seams generally have diverse and complicated geological characteristics. Intrinsic problems in mining such seams, such as large dip angle, short length of mining face, ineffective sealing and protection of working space by support systems, poor stability of equipment, …
The mining of coal resources in eastern China has entered the stage of deep mining, and many mines have reached the depth of 1000 meters. Different from shallow and moderate depth mining, the ...
open cast mining technology can play a vital role to full fill the demand of estimated coal production. As the open cast mining methods is a very financially cost effective mining methods which allows the high grade of mechanization and more, enormous creation volumes. In India, the opencast mining methods accounts for about 95 per cent of coal ...
coal seams are nos. 19 and 21 with a current mining rate of 360 m/a. e no. 21 coal seam must be rapidly extracted to enable in-pit dumping with a dumping track distance of 50 m. e dip of the no ...
The mineable coal seams include #4, #5, and #6, from which coal seam #4 is currently being mined. With an average burial depth of 400 m, the occurrence of coal seam #4 is stable. In addition, the thickness of the coal seam ranges from 1.8 m to 2.2 m, with the average thickness being 2 m. The dip angle of the coal seam is 43° to 47°, with the
School of Geosciences and Surveying Engineering, China University of Mining and Technology-Beijing, Beijing 100083, China; State Key Laboratory of Coal Resource and Safe Mining, China University of Mining and Technology-Beijing, Beijing 100083, China Chongliang Yuan Yaojie Coal and Power Group Company Ltd, Lanzhou 730080, China …
Through years of hardwork of predecessors in China, three types of mining methods for steeply inclined coal seams have been developed, including top-slicing …
