Results 11 to 20 of about 399,174 (293)
Energy Exploration & Exploitation, 2022 A thick-hard roof implies a large hanging-roof and high-frequency dynamic strata behaviour during mining, which may jeopardise personnel safety and equipment.
Baobao Chen, Changyou Liu, Bing Wang
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Directional hydraulic fracturing to control hard-roof rockburst in coal mines
International Journal of Mining Science and Technology, 2012 Abstract Hard roof is the main factor that induces rock-burst. In view of the present obvious weakness of control measures for hard roof rockburst in domestic collieries, the mechanism and field application of directional hydraulic fracturing technology for rock-burst prevention have been investigated in this paper using theoretical analysis and ...
Jun Fan +6 more
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Mechanism of Hydraulic Fracturing Cutting Hard Basic Roof to Prevent Rockburst [PDF]
Shock and Vibration, 2021 Rockburst is globally regarded as one of the most severe and complicated mining dynamic disasters to predict or control. Generally, the occurrence mechanism of rockbursts can be considered as a process of the elastic strain energy accumulation, emancipation, transmission, and occurrence.
Jianqiao Luo +6 more
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Generalization of trends in the influence of geomechanics factors on the choice of operation modes for the fastening system in the preparatory mine workings [PDF]
, 2000 Purpose. Substantiation of the mechanism of loading the preparatory mine working support to optimize its deformation-strength characteristics based on the calculation of the stress-strain state of the “massif – support” system.
Chervatiuk, V +4 more
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Bending Moment Characteristics of Hard Roof before First Breaking of Roof Beam Considering Coal Seam Hardening [PDF]
Shock and Vibration, 2018 The mechanical properties of a coal seam affect the distribution of support pressure. Considering the strain hardening effect of coal seam, the support pressure relationship of three zones—softened, hardened, and elastic—of a coal seam with regard to a hard roof is proposed, and methods to determine an approximate expression for the support pressure of
Shitan Gu +3 more
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A Method Based on Elastic Mechanics for Judging Compound Hard Roof and Its Application
Shock and Vibration, 2020 Compound hard roof overlying coal face is the common disaster factor leading to strong strata behaviors. To solve the long-standing problems of only considering partial factors and large deviation from the actuality when identifying compound hard roof, a
Haiyang Wang +6 more
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Shock and Vibration, 2021 In order to study the fracture patterns of hard main roof in longwall top coal caving (LTCC) with large mining height, a two-dimensional physical similarity model was created to simulate the mining process of No.
Jinkai Liu +3 more
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矿业科学学报, 2021 Yima coal field has an extra-thick hard rock strata, which is the main cause of many dynamic disasters in the mining area. Based on the mining face 21221 of Qianqiu mine in Yima coal field, Henan Province, China, this paper studies the movement ...
Wang Hongwei +5 more
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Mechanical Analysis of the First Fracture Characteristics of Hard Roof of Extra-thick Coal Seam
Meikuang Anquan, 2020 In order to investigate the failure mechanisms of the hard roof in the fully mechanized caving face in the extra-thick coal seam, the mechanical analysis model of the first breaking of the hard top roof in the fully mechanized caving mining of the extra-
LIANG Shaping, LU Yinlong, GUO Peng, WU Bingzhen
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Carbon and nutrient losses during manure storage under traditional and improved practices in smallholder crop-livestock systems - evidence from Kenya [PDF]
, 2009 In the absence of mineral fertiliser, animal manure may be the only nutrient resource available to smallholder farmers in Africa, and manure is often the main input of C to the soil when crop residues are removed from the fields.
Giller, K.E. +3 more
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