Coal pillar safety and surface deformation characteristics of wide strip pillar mining in deep mine

Guo, Wei; Wang, Hailong; Chen, Shaojie

doi:10.1007/s12517-015-2233-5

Cited by 42 publications

(30 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, many different types of mining methods have been successfully applied to control overburden and surface damage when mining under buildings or other structures, such as strip mining [8,9], harmonic mining [10], room mining [11], grout injection [12] and backfill mining [13][14][15].…”

Section: Introductionmentioning

confidence: 99%

Roadway Backfill Mining with Super-High-Water Material to Protect Surface Buildings: A Case Study

et al. 2019

View full text Add to dashboard Cite

As coal resources trapped under surface buildings in the Wangtaipu coal mine area impede the efficient mining of coal seams and constrain the sustainable development of coal mines, a super-high-water roadway backfill mining technique for preventing building damage was adopted. According to the control principle and theoretical calculations, an engineering design was established including the reasonable width of segment coal pillars in the working face and technical parameter design. The monitoring results after the implementation of the scheme showed that building deformation was controlled within grade I, protecting the surface buildings. A reasonable roadway design parameter was achieved, with a surface subsidence of 27 mm and horizontal deformation of 0.3 mm/m, indicating that it can ensure the safety of surface buildings from the State Bureau of Coal Industry. The practical trial can provide a reference for the extraction of coal resources under similar conditions and is vital for the sustainable development of the mining industry and economic growth. This is because the remaining coal pillar can usually support the overburden load, allowing slight surface movement and deformation. Although the strip mining or room mining method has reduced surface subsidence or damage to a certain extent, the mining rate is low due to the coal pillars. Because the harmonic mining is limited by many factors, such as construction organization, geological conditions, and subsidence factor, it is difficult to realize. Meanwhile, grouting injection technology has been successfully applied to reduce surface subsidence and building damage in populated areas. Alehossein [16] studied shear behaviour of the slurry through field and laboratory testing, and derived formulas for minimum pump pressure and local pressure, and the results are consistent with each other. Shen and Poulsen [17] used numerical modeling to study the evolution of horizontal fractures at bed separations during longwall mining. By analyzing the influence of filling ratio and maximum subsidence on the grouting effect, Xuan and Xu [18] obtained the supporting width that was formed at the center of the gob. Subsequently, the stiffness and distribution of the grouting mass were investigated through field borehole, and the mechanism of grouting to restrain the overburden deformation was revealed [19]. Considering the long-term stability of overburden, the effect of harmonic mining and grouting injection on overburden damage reduction is poor. In fact, the essential problem of "under-three" mining is controlling the movement and deformation of the overlying strata. By contrast, backfill mining has been widely used and is becoming an effective technique for reducing the degree of overburden failure in the green mining technical system, and has been developed to solve the global problems described above, especially for "under-three" mining [20][21][22][23]. In essence, backfill mining reduces the overburden movement by replacing the coal with backfill material. Meanwhile, ...

show abstract

Section: Introductionmentioning

confidence: 99%

Roadway Backfill Mining with Super-High-Water Material to Protect Surface Buildings: A Case Study

et al. 2019

View full text Add to dashboard Cite

show abstract

“…As a result, the gas in coal desorbs rapidly, and sometimes, it can lead to abnormal gas emissions, which results in serious disasters, such as gas explosions or coal and gas outbursts (“outbursts” for short) . Furthermore, after a coal seam is mined, the fallen rocks stack disorderly in the goaf with a large loose coefficient, which results in the gas flowing into the goaf along the cracks . The difference in the gas concentration between the goaf and the working face results in gas convection in the goaf and in the working face until the new dynamic equilibrium is reached.…”

Section: Introductionmentioning

confidence: 99%

“…extremely thick coal seam, gas emission, goaf, hard roof, roof weighting cracks. [18][19][20][21][22] The difference in the gas concentration between the goaf and the working face results in gas convection in the goaf and in the working face until the new dynamic equilibrium is reached.…”

Section: Introductionmentioning

confidence: 99%

Effect of roof movement on gas flow in an extremely thick coal seam under fully mechanized sublevel caving mining conditions

Guo

Cui

et al. 2019

Energy Science & Engineering

View full text Add to dashboard Cite

The abnormal emission of gas in coals is the main factor that induces serious gas disasters in coal mines. During the coal mining process, roof movement has important effects on the gas emission law and gas flow characteristics. In this study, an extremely thick coal seam under fully mechanized sublevel caving mining conditions from the Tashan coal mine in China was used as an example; the effect of roof weighting on gas emission in the goaf was studied. Then, the large roof weighting step and the small roof weighting step caused by the different thicknesses of lamprophyre breakage were used as the objects and a numerical simulation study on the gas flow characteristics in the goaf was carried out. The results indicate that the mining coal seams, the overlying adjacent unmined coal seams, and the goaf are the main contributors to the large gas emission capacity, and even situations exist where the gas concentration exceeds the limit in the working face. During roof weighting, the gas concentration and emission capacity in the return airway, upper corner, and high drainage roadway increase substantially. The results of the numerical analysis are in good agreement with the observed data, which indicates that it is effective to control the gas in coal seams by designing the location of high drainage roadway according to the mining characteristics of coal seam and the gas emission law.

show abstract

“…These include strip mining (Guo et al , 2016Zhang et al 2011a, b;Xu et al 2012), harmonic mining (Yu et al 2004), and backfill mining (Guo et al 2009(Guo et al , 2014Huang et al 2011;Zha et al 2011;Xu et al 2013;Zhang et al 2014Zhang et al , 2015. The basic practice of strip mining divides the areas to be exploited into formal stripped shapes.…”

Section: Introductionmentioning

confidence: 99%

Mining scheme design for super-high water backfill strip mining under buildings: a Chinese case study

Guo

Zhai

2016

Environ Earth Sci

View full text Add to dashboard Cite

Considerable coal resources are buried under buildings in No. 5 mining area of Hengjian Coal Mine, which greatly shortens its service life. Working on the premise that the degree of mining-induced damage to surface buildings should not exceed the protective indicator, the mine proposes to use super-high water backfill technology so as to ensure maximum exploitation of these resources. However, according to monitoring of observations of surface movement in the first-mined 2515 working face, mining-induced damage to the surface buildings will exceed level I if this technology is also used to exploit other working faces. A technology combining super-high water backfilling with strip mining is proposed. Numerical simulation is used to study the influence of different retaining pillar widths on surface subsidence characteristics. A reasonable design of these combined technologies is achieved based on the numerical simulation and theoretical analysis. Predicted results indicate that the designed scheme can ensure the safety of the surface buildings. These research results provide a reasonable and reliable technical solution for mining of coal resources buried under buildings.

show abstract

Coal pillar safety and surface deformation characteristics of wide strip pillar mining in deep mine

Cited by 42 publications

References 1 publication

Roadway Backfill Mining with Super-High-Water Material to Protect Surface Buildings: A Case Study

Roadway Backfill Mining with Super-High-Water Material to Protect Surface Buildings: A Case Study

Effect of roof movement on gas flow in an extremely thick coal seam under fully mechanized sublevel caving mining conditions

Mining scheme design for super-high water backfill strip mining under buildings: a Chinese case study

Contact Info

Product

Resources

About