A rationally designed support for deep roadways excavated in broken soft rock under high stress was investigated. The deformation and failure characteristics and the mechanism of ''yielding support'' w...A rationally designed support for deep roadways excavated in broken soft rock under high stress was investigated. The deformation and failure characteristics and the mechanism of ''yielding support'' was studied for anchor bolts and cables. The rail roadway of the 2-501 working face in the Liyazhuang Mine of the Huozhou coal area located in Shanxi province was used for field trials. The geological conditions used there were used during the design phase. The new ''highly resistant, yielding'' support system has a core of high strength, yielding bolts and anchor cables. The field tests show that this support system adapts well to the deformation and pressure in the deep broken soft rock. The support system effectively controls damage to the roadway and ensures the long term stability of the wall rock and safe production in the coal mine. This provides a remarkable economic and social benefit and has broad prospects for fur- ther application.展开更多
In this paper, the ability to ignite methane of water-carrying explosives is discussed in detail. The difference of the safety towards methane of water- carrying explosives and ammonite is analysed comparatively. lt i...In this paper, the ability to ignite methane of water-carrying explosives is discussed in detail. The difference of the safety towards methane of water- carrying explosives and ammonite is analysed comparatively. lt is shown that the process of detonation reaction, the duration of fIame by combustible residues of detonation and the fineness of cooling salt in detonation products are important factors of the safety of explosive towards methane. Water-carrying explosives are safer than ammonite used in coal mines.展开更多
基金supported by the National Natural Science Foundation of China (No. 50874103)the National Basic Research Program of China (No. 2010CB226805)+1 种基金the Natural Science Foundation of Jiangsu Province (No. BK2008135)as well as by the Open Foundation of State Key Laboratory of Geomechanics and Deep Underground Engineering (No. SKLGDUEK0905)
文摘A rationally designed support for deep roadways excavated in broken soft rock under high stress was investigated. The deformation and failure characteristics and the mechanism of ''yielding support'' was studied for anchor bolts and cables. The rail roadway of the 2-501 working face in the Liyazhuang Mine of the Huozhou coal area located in Shanxi province was used for field trials. The geological conditions used there were used during the design phase. The new ''highly resistant, yielding'' support system has a core of high strength, yielding bolts and anchor cables. The field tests show that this support system adapts well to the deformation and pressure in the deep broken soft rock. The support system effectively controls damage to the roadway and ensures the long term stability of the wall rock and safe production in the coal mine. This provides a remarkable economic and social benefit and has broad prospects for fur- ther application.
文摘In this paper, the ability to ignite methane of water-carrying explosives is discussed in detail. The difference of the safety towards methane of water- carrying explosives and ammonite is analysed comparatively. lt is shown that the process of detonation reaction, the duration of fIame by combustible residues of detonation and the fineness of cooling salt in detonation products are important factors of the safety of explosive towards methane. Water-carrying explosives are safer than ammonite used in coal mines.
