Results 151 to 160 of about 1,416 (183)

Drawing mechanism of fractured top coal in longwall top coal caving

International Journal of Rock Mechanics and Mining Sciences, 2020
Abstract This work proposed a progressive-sectional failure model (PSFM) based on Particle Flow Code (PFC) to simulate top coal drawing process in longwall top coal caving (LTCC) mining. The progressive-sectional fracturing of top coal was reproduced in simulation.
Zhengyang Song, Heinz Konietzky, Martin Herbst   +2 more
openaire   +1 more source

Modeling Top Coal Disintegration in Thick Seams in Longwall Top Coal Caving

Journal of Mining Science, 2019
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.
V. I. Klishin, V. N. Fryanov, L. D. Pavlova, G. Yu. Opruk   +3 more
openaire   +2 more sources

Study of automated top-coal caving in extra-thick coal seams using the continuum-discontinuum element method

International Journal of Rock Mechanics and Minings Sciences, 2019
In order to investigate top-coal drawing regularity and automated top-coal caving technology in extra-thick coal seams, an approach coupling the particle element and the block element is presented based on the continuum-discontinuum element method (CDEM).
Qunlei Zhang, Jinchao Yue, Chun Feng
exaly   +2 more sources

A discontinuum modelling approach for investigation of Longwall Top Coal Caving mechanisms

International Journal of Rock Mechanics and Minings Sciences, 2018
This paper presents a discontinuum modelling approach to investigate Longwall Top Coal Caving (LTCC) behaviour including stress distribution, coal and rock failures, top coal caving and roof strata rupture, and to analyse the impact of overburden ...
Tien Dung Le, Joung Oh, Bruce Hebblewhite   +2 more
exaly   +2 more sources

Force chains in top coal caving mining

International Journal of Rock Mechanics and Mining Sciences, 2020
Abstract During the top coal caving mining, rock mass becomes fractured, and the physical status of top coal and overlying strata in the vicinity of the working face changes from continuous to discontinuous medium. It is considerably difficult to explain in theory the transition and action of mining-induced pressure in discrete top coal and fractured
Jin-an Wang, Liu Yang, Fei Li, Chao Wang
openaire   +1 more source

Caving mechanisms of loose top-coal in longwall top-coal caving mining based on stochastic medium theory

Arabian Journal of Geosciences, 2018
A good understanding of the caving mechanisms of loose top-coal is significant for longwall top-coal caving (LTCC) mining. In this paper, the equations of the particle motion, top-coal boundary, and drawing body were derived based on the stochastic medium theory. Then, the particles moving boundary and the shape of the top-coal loss were discussed, and
Dijie Zhu, Zhonghui Chen, Weisheng Du, Lingfan Zhang, Zihan Zhou   +4 more
openaire   +1 more source

Application of fractal theory to top-coal caving

Chaos, Solitons & Fractals, 2008
Abstract The experiences of underground coal mining in China show that coal in a thick hard coal seam with a hard roof, the so-called “double hard coal seam”, is difficult to be excavated by top-coal caving technique. In order to solve the problem, a top-coal weakening technique is proposed in this paper.
H. Xie, H.W. Zhou
openaire   +1 more source

Theoretical equation of initial top-coal boundary in longwall top-coal caving mining

International Journal of Mining and Mineral Engineering, 2018
The theoretical equation of initial top-coal boundary (ITCB) is one of the fundamental problems of top-coal drawing law in longwall top-coal caving (LTCC) mining. The granular mechanical model of ITCB is established based on loose medium flow field theory.
jie Wei, Zhengyang Song, Jinwang Zhang
openaire   +1 more source

Longwall Top Coal Caving Mechanisms in the Fractured Thick Coal Seam

International Journal of Geomechanics, 2020
Abstract In this study, the finite difference method (FDM) coupled with a discrete fracture network (DFN) was utilized to analyze longwall top coal caving (LTCC) behaviors.
Jiachen Wang, Zhaohui Wang, Yang Li
openaire   +1 more source

Study on the abutment pressure distribution in top coal caving

Arabian Journal of Geosciences, 2020
The investigation on the deformation and failure of top coal and its roof strata is the key topic of fundamental research of the fully mechanized top coal caving method. In this paper, the mechanical model of continuous damage and failure of top coal is established based on damage mechanics and statistical strength theory.
Bin Yu, Lingfan Zhang
openaire   +1 more source