Results 41 to 50 of about 7,991 (237)

Development status and Prospect of directional hydraulic fracturing technology for coal mine roof [PDF]

E3S Web of Conferences, 2020
Aiming at the harm and control methods of thick and hard roof in coal mine, the paper firstly analyzes the advanced control methods of thick and hard roof, such as directional shaped charge blasting roof control technology, hydraulic fracturing roof ...
Liangwei LI
doaj   +1 more source

The Breaking Span of Thick and Hard Roof Based on the Thick Plate Theory and Strain Energy Distribution Characteristics of Coal Seam and Its Application [PDF]

, 2017
In mining engineering, the thick and hard roof threatens the safe production. Based on Reissner plate theory and combined with weighted residual method, with four edges clamped as the boundary conditions, this paper deduces the theoretical formula of the
Xiaolong Li, Changwu Liu, Yang Liu, Hui Xie   +3 more
core   +1 more source

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
doaj   +1 more source

Analysis of coal pillar rock burst appearance in multi-seam mining with thick and hard roof

, 2022
The existing research only analyzes the rock burst appearance characteristics under specific conditions, lacks research on the rock burst appearance induced by coal pillar under the condition of thick and hard roof. In order to solve this problem, taking
ZHOU Chao, ZHONG Taoping, LI Zhenlei, LI Hongping, LAN Shirui, SONG Dazhao, YANG Wei, ZHANG Chuanjiu   +7 more
core   +1 more source

Pressure Control Technology at the Hard Thick Sandstone Roof in an Island Mining Face with a Large Mining Height

, 2020
Fracture of a critical stratum on a coal seam roof may cause strong strata pressure behaviours. In particular, a large-scale sudden fracture of the critical stratum, which is formed by hard thick sandstones on a mining face with a large mining height ...
Min Tu, Tu, Min, Fu*, Baojie, Qingchong Zhao, Baojie Fu*, Zhao, Qingchong   +5 more
core   +1 more source

Research on the bearing characteristics of brackets in thick hard roof mining sites and the effect of blasting on roof control

Geomechanics and Geophysics for Geo-Energy and Geo-Resources
AbstractDeep mining stress increase and thick hard rock layer endowment drive rock body fissure expansion, leading to sudden fracture of the roof plate accidents. The roof slab of 11,129 working face in Zhangji Mine is a 16 m thick sandstone composite roof slab, whose compressive strength reaches 89.8 MPa.
Jiaxin Dang, Min Tu, Xiangyang Zhang, Qingwei Bu   +3 more
openaire   +2 more sources

Migration characteristics and disaster reduction and erosion prevention mechanism of thick and hard roof in deep filling mining

Meitan kexue jishu
To address the issue of rock burst disasters induced by the fracture of thick-hard roof strata, focuses on deep thick and hard roof. By integrating theoretical analysis, engineering experiments, and field monitoring, the fracture characteristics of thick-
Erhu BAI, Ranlie WANG, Wenbing GUO, Yi TAN, Hui LI, Xueyi LI, Sulin CHENG   +6 more
doaj   +1 more source

Collaborative application of directional blasting presplitting and flexible formwork concrete wall technologies in Chengzhuang Coal Mine

Meikuang Anquan, 2022
In order to improve the recovery rate of coal resources in general, Chengzhuang Coal Mine has carried out and implemented the technology of gob-side entry retaining in 5309 large height mining face.
SI Xiaopeng, ZHOU Changtai
doaj   +1 more source

Theory and technical system of control of far-near field hard roofs from ground and underground in a large space stope

Meitan xuebao, 2023
The stope space, after mining an extra-thick coal seam with hard roofs, is large, and its law of mining pressure is complex. The mechanism of strong mine pressure action for this stope is unclear, and there is a lack of multi-point control technology ...
Bin YU, Yang TAI, Tiejun KUANG, Rui GAO, Jingxuan YANG, Binwei XIA, Weibing ZHU, Yong LI   +7 more
doaj   +1 more source

Compliant Pneumatic Feet with Real‐Time Stiffness Adaptation for Humanoid Locomotion

Advanced Robotics Research, EarlyView.
A compliant pneumatic foot with real‐time variable stiffness enables humanoid robots to adapt to changing terrains. Using onboard vision and pressure control, the foot modulates stiffness within each gait cycle, reducing impact forces and improving balance. The design, cast in soft silicone with embedded air chambers and Kevlar wrapping, offers durable,
Irene Frizza, Hiroshi Kaminaga, Philippe Fraisse, Gentiane Venture   +3 more
wiley   +1 more source