تقنية تعدين الفحم Longwall Top Caving
Strata movement and shield pressure analysis at Tongxin longwall top
Roof strata movement and shield pressure are two important factors that affect the production and efficiency of longwall top coal caving LTCC method in extra thick coal seams The performances of these two aspects can be very different from one mine to another depending on the roof strata conditions In this paper the geological conditions of the LTCC 8202 panel
Caving Underground Mining Methods longwall Sublevel caving…
5 Longwall Stoping Longwall stoping is applicable to bedded deposits of uniform shape limited thickness and large horizontal extension a coal seam a potash layer or the reef the bed of quartz pebbles exploited by gold mines in South Africa It is a caving method particularly well adapted to relatively flat lying thin planar deposits or horizontal
In situ investigations into overburden failures of a super
DOI / Corpus ID 131678260; In situ investigations into overburden failures of a super thick coal seam for longwall top coal caving article{Yu2015InSI title={In situ investigations into overburden failures of a super thick coal seam for longwall top coal caving} author={Bin Yu and Jun Zhao and Tiejun Kuang and Meng Xiangbin}
3D numerical modeling of longwall mining with top coal caving
Longwall top coal caving mechanisms and cavability optimization with hydraulic fracturing are analysed in this study Based on the geological and geotechnical conditions of the Dongzhouyao coal
A study into the feasibility of application of longwall top coal caving
Longwall Top Coal Caving method The Longwall Top Coal Caving LTCC method is basically a combination of the traditional longwall method and the caving of top coal during the process of mining operations The original name of the LTCC method was the Soutirage" method Nath 1979; Proust 1979 In the LTCC method the panel is created
Caving mechanisms of loose top coal in longwall top coal caving
The top coal caving longwall mining was successfully put on trials in Yangquan Mining Bureau in 1988 and Lu an Mining Bureau in 1989 At the same time research on the top coal caving mining in steeply inclined thick coal seams began with good results [5]
A new cavability assessment for Longwall Top Coal Caving
A number of assessment criteria for top coal cavability have been developed and utilised in evaluating LTCC s applicability in practice The criteria however have not sufficiently represented fundamental rock behaviours associated with LTCC mining such as intact rock failure discontinuity failure and/or explicit rock caving and this may result in assessment
Evaluation of mine scale longwall top coal caving parameters
1 Introduction Longwall Top Coal Caving LTCC is an underground mining method developed for thick seam extraction Depending on the coal seam condition various layouts can be considered for the LTCC [1] The full seam height LTCC mining layout has been chosen for this work as it takes full advantage of support pressure in fracturing and breaking
Investigation of the effect of caving height on the efficiency
The longwall top coal caving LTCC production method applied by forming a face in the horizontal thickness of the seam and also called horizontal section top coal caving especially in studies originating from China is widely used in the production of inclined and thick coal seams In this production method in addition to the top coal
Boundary quantitative characterization of the top coal limit
Fully mechanized top coal caving mining is one of the main methods of thick seam mining 1 2 3 4 coal is the only load transfer medium between support and roof and its physical and
PDF Longwall top coal caving LTCC mining technologies
The longwall top coal caving LTCC is a widely used method for producing thick coal seams This method is applied in two different ways in steeply inclined thick coal seams by forming a longwall
A novel non‐pillar coal mining technology in longwall top coal caving
In longwall top coal caving LTCC mining methods problems such as large deformations loss of coal resources and excavation relay out of balance are often encountered with the increased production in single mining panels To address these problems a novel non‐pillar coal mining technology in LTCC was used based on the equilibrium mining theory
APLICABILIDADE DO MÉTODO DE LAVRA
This paper presents a mining technology that enables the continuous conversion from top coal caving TCC to multi slice mining MSM The technology helps operations overcome challenges with mining thick bifurcated coal seams particularly the challenge of rock parting seams affecting the caving of TCC mining methods Findings show
Geotechnical Considerations for Longwall Top Coal
LONGWALL TOP COAL CAVING DESCRIPTION Longwall Top Coal Caving LTCC is an enhanced form of the conventional longwall recovery system whereby a rear Armoured Face Conveyor AFC refer to Figure 3 is utilised to extract coal from behind the powered supports that would otherwise be left unrecovered in thick seam environments The
Investigation of the effect of caving height on the efficiency
The longwall top coal caving LTCC production method applied by forming a face in the horizontal thickness of the seam and also called horizontal section top coal caving especially in studies originating from China is widely used in the production of inclined and thick coal this production method in addition to the top coal losses that occur behind the
Modeling Top Coal Disintegration in Thick Seams in Longwall Top Coal Caving
The geomechanical model of the powered roof support top coal roof rock system is developed For investigation of disintegration processes in top coal of thick seam numerical modeling with finite element discretization of a study domain is carried out using the authors original code The computational experiment reveals stress distribution in rock mass
A new cavability assessment for Longwall Top Coal Caving
A number of assessment criteria for top coal cavability have been developed and utilised in evaluating LTCC s applicability in practice The criteria however have not sufficiently represented fundamental rock behaviours associated with LTCC mining such as intact rock failure discontinuity failure and/or explicit rock caving and this may result in assessment
[PDF] Numerical modeling of longwall top coal caving
Thar Coalfield in Pakistan is the largest reserve of lignite coal in the country which is outlined by thick coal seams The preferred mining method for these thick coal seams is the Longwall Top Coal Caving LTCC The connection of both the top coal caving and its compactness are still rare; therefore the capability of top coal caving mechanism is the most
Dynamic sublevel caving technology for thick seams with
Dynamic sublevel caving technology DSCT proposed by the researchers is one of effective methods to solve the problems of low top coal recovery poor drawing balance and support stability in longwall top coal caving LTCC with large dip angle To investigate the reasonable number of supports in a sublevel N and the top coal drawing mechanisms under
Effect of Key Parameters on Top Coal First Caving and Roof
The first caving of top coal and the first weighting of roof strata in Longwall Top Coal Caving LTCC mining were analyzed in a parametric study by using a discontinuum modeling technique with
A new cavability assessment for Longwall Top Coal Caving
This paper presents a new criterion for assessing top coal cavability in Longwall Top Coal Caving mining technology Top coal Cavability Index TCI criterion was developed through a parametric
Caving mechanisms of loose top coal in longwall top coal caving
Longwall Top Coal Caving LTCC is considered one of the most efficient methods for mining thick coal seams Compared to other thick seam mining methods LTCC can offer significantly reduced
Geotechnical Considerations for Longwall Top Coal
LONGWALL TOP COAL CAVING DESCRIPTION Longwall Top Coal Caving LTCC is an enhanced form of the conventional longwall recovery system whereby a rear Armoured Face Conveyor AFC refer to Figure 3 is utilised to extract coal from behind the powered supports that would otherwise be left unrecovered in thick seam environments The
Study on Roof Instability Effect and Bearing Characteristics of
In longwall top coal caving LTCC due to the fracture and migration of top coal the roof will break and collapse which causes serious impact damage to hydraulic support Therefore we aimed to reveal the relationship between the roof instability effect and the bearing characteristics of hydraulic support in the LTCC face Based on the occurrence conditions of
Critical Aspects of Longwall Top Coal Caving Method for
Wang J Zhang J Song Z Li Z 2015 Three dimensional experimental study of loose top coal drawing law for longwall top coal caving mining technology J Rock Mech Geotech Eng 7 318 326 Article Google Scholar Wang J Wang Z Li Y 2020 Longwall top coal caving mechanisms in the fractured thick coal seam