Based on techniques of close upper protective coal-rock layer mining, relieved gas extraction, and underground gangue washing-discharging-backfilling, this paper initiates the concept of mixed fully-mechanized coal mining, which combines a solid backfilling method and a caving method (hereinafter referred to as “backfill and caving mixed mining”). After the principle and key techniques are intr...

Rapid development of coal deep mining equipment and technology, that is connected with widespread introduction of high-performance longwall sets of equipment is accompanied with an increase of economic losses in case of its possible downtime. The analysis of dismantling experience in modern Russian mines has shown that in absolute majority of cases the actual duration of re-assembling with rega...

Land surface deformation can be caused by underground mining activities. The maximum subsidence normally occurs directly above the location of the excavation of the coal seam. In the case where the longwall mining technique is applied, the magnitude and shape of the subsidence bowl are constrained by the longwall structure (pillar). This paper describes the use of satellite radar interferometry...

ROBERT A. HANEY Mine Safety and Health Administration, Pittsburgh Health Technology Center The effectiveness of these dust control techniques has been evaluated primarily through the use of instantaneous dust measurements. These instantaneous dust measurements give a relative indication of whether dust control and -------------------~ employee exposure improve or deteriorate. Because the instan...

in advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. the gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (edz) above the gate roadway and 2) loading effect due to the caving zone (cz) above the longwall w...

The paper begins by outlining the role and importance of coal as a source of energy and in the steel industry. It briefly describes the longwall method of working together with the conventional machinery used in the method. A mathematical model is then proposed that shows the relationship between the gradient of the coal seam, that of the face and the entries to the panel. Determination of a mo...

The key to the safe mining of thick coal seams under rivers is understanding the development patterns of fractured water-conducting zones (FWCZ) when various mining methods are used. To solve this problem, we employed numerical simulation to investigate FWCZ when slice mining and longwall caving mining are performed. When slice mining was carried out, the maximum height of the FWCZ in the highe...

Coal is an important fossil fuel and will also be for the next decades [1]. The only way to achieve the challenges faced by the coal industry is to reduce production costs by improving productivity. Improvement of productivity has become an important goal for today’s coal industry in the race to increase price competitiveness. In recent years, underground mining method is becoming popular becau...

Noise is one of the most pervasive health hazards in mining. A compilation of Mine Safety and Health Administration (MSHA) noise survey data for Fiscal year 1990 shows that approximately 40% of the total samples taken for longwall occupations exceeded the Permissible Exposure Limit (PEL) of 100% [Gigliotti et al. 1991]. In order to properly determine workers’ exposures on longwall coal mining s...

In this paper the Kamat-Riley (K-R) event-based Monte Carlo simulation method was used for reliability analysis of longwall shearer machine. Shearer machine consists of six subsystems; water, haulage, electrical, hydraulic, cutting arms and cable systems in a series network configuration. A shearer in the Tabas coal mine was selected as case study and its all failure data were collected and use...