期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
Energy-limiting factor for coal and gas outburst occurrence in intact coal seam 被引量:3
1
作者 Qingyi Tu Yuanping Cheng +2 位作者 Sheng Xue Ting Ren Xiang Cheng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第4期729-742,共14页
This research reviewed the mechanics and gas desorption properties of intact coal,and tested the crushing work ratios of different intact coals,and then,studied the stress conditions for the failure or crushing of int... This research reviewed the mechanics and gas desorption properties of intact coal,and tested the crushing work ratios of different intact coals,and then,studied the stress conditions for the failure or crushing of intact coal and the gas demand for the pulverization of intact coal particles.When a real-life outburst case is examined,the required minimum stress for intact coal outburst is estimated.The study concludes that the crushing work ratios of three intact coal samples vary from 294.3732 to 945.8048 J/m^(2).For the real-life case,more than 2300 MJ of transport work is needed,and 10062.09,7046.57 and 5895.47 m^(3) of gas is required when the gas pressure is 1,2 and 3 MPa,respectively.The crushing work exceeds the transport work and even reaches 13.96 times of the transport work.How to provide such an enormous crushing work is an energy-limiting factor for the outburst in intact coal.The strain energy is needed for the crushing work,and the required minimum stress is over 54.35 MPa,even reaching 300.44 MPa.These minimum stresses far exceed the in-situ vertical and horizontal stresses that can be provided at the 300–700 m mining depth range. 展开更多
关键词 Coal and gas outburst Intact coal crushing work ratio Geological factors Outburst energy
下载PDF
An estimation model for the fragmentation properties of brittle rock block due to the impacts against an obstruction 被引量:3
2
作者 HOU Tian-xing XU Qiang +2 位作者 XIE Hong-qiang XU Nu-wen ZHOU Jia-wen 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1161-1173,共13页
Mountain hazards with large masses of rock blocks in motion – such as rock falls, avalanches and landslides – threaten human lives and structures. Dynamic fragmentation is a common phenomenon during the movement pro... Mountain hazards with large masses of rock blocks in motion – such as rock falls, avalanches and landslides – threaten human lives and structures. Dynamic fragmentation is a common phenomenon during the movement process of rock blocks in rock avalanche, due to the high velocity and impacts against obstructions. In view of the energy consumption theory for brittle rock fragmentation proposed by Bond, which relates energy to size reduction, a theoretical model is proposed to estimate the average fragment size for a moving rock block when it impacts against an obstruction. Then, different forms of motion are studied, with various drop heights and slope angles for the moving rock block. The calculated results reveal that the average fragment size decreases as the drop height increases, whether for free-fall or for a sliding or rolling rock block, and the decline in size is rapid for low heights and slow for increasing heights in the corresponding curves. Moreover, the average fragment size also decreases as the slope angle increases for a slidingrock block. In addition, a rolling rock block has a higher degree of fragmentation than a sliding rock block, even for the same slope angle and block volume. Finally, to compare with others' results, the approximate number of fragments is estimated for each calculated example, and the results show that the proposed model is applicable to a relatively isotropic moving rock block. 展开更多
关键词 Rock block Rock fragmentation Rock movement process crushing work ratio Average fragment size
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部