An extraction method for deep-seated thick seam deposits by underground mining with high resource recovery has remained a great challenge Indian engineers, whereas the longwall top coal caving (LTCC) evolved as an effective various geo conditions in China and other counties. The percentage of (TCR) plays predominant role determining feasibility LTCC, which relies on First Top Coal Caving Distan...

In longwall top coal caving (LTCC), due to the fracture and migration of coal, roof will break collapse, which causes serious impact damage hydraulic support. Therefore, we aimed reveal relationship between instability effect bearing characteristics support in LTCC face. Based on occurrence conditions 08 mining area Shilawusu Coal Mine, model upper immediate was established, working resistance ...

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...

Abstract This review details the state of art in research on top coal drawing mechanisms Longwall t op c oal aving (LTCC) by examining relevant literature over last two decades. It starts with an introduction brief history and basic procedures LTCC. The framework mechanism, concepts, some theoretical models LTCC are detailed sect. mechanism. authors note that T d rawbody (TCD), b oundary (TCB) ...

Thick coal seam no. 3, block V, Lupeni mine was mined by longwall top caving (LTCC). After the mining, ground surface underwent continuous subsidence, but since 2008, three sinkholes have appeared on with important dimensions, atypical for geo-mining conditions in this basin. This article is a synthesis of study meant to decipher geo-mechanical phenomenon that led emergence these and highlighti...

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...

Abstract In the process of longwall top coal caving, selection caving interval along advancing direction working face has an important effect on recovery. To explore a realistic face, panel 8202 in Tongxin Coal Mine is used as example, and 30 numerical simulation models are established by using Continuum-based Distinct Element Method software to study recovery with 4.0 m, 8.0 12.0 16.0 20.0 m 2...

Abstract High rock stress and ground temperature pose great threats to the routine production of longwall top coal caving (LTCC) panels. In this risky condition, width chain pillar is considered a factor adjustable for controlling burst goaf ignition hazards. However, contradiction, as suggested by experience, that narrowing helps prevention but negatively leads higher self-ignition potentials,...

Abstract A probabilistic risk assessment framework was developed to mathematically represent the complex engineering phenomena of rock bursts and gas outbursts for a heterogeneous coal seam. An innovative object-based non-conditional simulation approach used distribute lithological heterogeneity present in seam respect their geological origin. The changing mining conditions during longwall top ...