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1 coal in the national energy market position and role of energy in economic development, social progress, the main support conditions. Table 1 shows that in 1994 the world's primary energy consumption,vibram five fingers outlet, fossil energy resources (coal, oil, natural gas) accounted for more than 90%, nuclear power, hydropower 7.2%, 2.5%. In the next few decades, fossil energy resources will continue to dominate the 1994 World primary energy consumption in China's energy resources, coal is 3.3 times the water is 17 times the oil and gas, accounting for 73.4%; in fossil energy resources, coal accounted for 94.3% (Table 2). Coal is China's most important energy resources. Table 2 China's energy resources, the distribution of the types of social and economic life in our primary energy consumption, coal accounts for 75% of coal is China's primary energy. According to statistics, coal provides 75% of industrial fuel, 76% of fuel for power generation, 80 percent of the civilian commercial energy, 60% of chemical raw materials. Can be seen, the coal industry is to support economic development and protection of people's lives based industries. As the occurrence of our resources, our recent coal-dominated energy structure will not have changed much. Experts predict that by 2050, coal's share in China's energy is still to reach 50%. At present, China's economic development relies heavily on coal energy supporting role.
Keywords coal mine shaft fracture prevention; polymer; safety factor; coal efficiency

6 grouting materials, grouting materials selection should follow the principle of choice (1) to improve the mechanical properties of rock mechanical properties such as strength and deformation resistance, commonly used in cement-based material only or the use of high-strength pulp chemical pulp only. (2) for the purpose of plugging seepage, should be used to inject, mobility are superior gel time can be adjusted to cut pulp wood. (3) grouting in rock fissures, generally one should use water mixed with a small amount of mud or bentonite slurry or ultrafine cement materials. In the selection of fine sand slurry material, chemical pulp only; silt and soft clay --- silicate cement grout should be used in the loess and other alkaline sodium silicate grout. (4) should be considered in the choice of grout into the rock layers in the grouting acid, alkali or organic matter, etc., is reacted with the grouting material occurs resulting materials hazardous chemical denaturation. Mud and water will not harden with humus, acid curing and lime slurry injection into the shell, there will be a bottomless pit without a trace, but the opposite is generally alkaline water glass and wet loess soil layer is conducive to enhancing the strength. (5) in the same stratum can use one or several compound grouting grouting materials, not only economic and effective. According to a chemical grout setting time is short,GHD Glätteisen günstig, easy flow,radii shoes sale, good and easy to inject the control advantages of a large gap in the center line into the water, mud, and then cross-perfusion can be admitted and good chemical pulp to reduce the project's bid to take the satisfactory results

2 China mine shaft wall vandalized since the 1980s, China's per mine shaft there is a rare geological disasters abroad, ie non-mining of the wall rupture. Light of this disaster has caused the deformation and fracture wall, water seepage, may cause the card to re-pot, Chung Chung sand, or even stop, not only to serious coal mine production safety risks, but also coal mining enterprises to bear huge losses. According to incomplete statistics, since 1987, China's eastern region to create a shaft in deep soil layers up to the destruction of more than 80 (the end of 2004), due to rupture caused by the mine shaft as much as over one billion yuan of economic loss was well as the construction industry since the founding of China experienced the largest, the deepest one of the longest technical problems. China's eastern wall rupture involving the hardest hit Jiangsu, Shandong and Anhui three provinces more than 100 mines were in Xuzhou, Datun, Huaibei and other big coal. Datun Coal following the example in Table 3.

3 mine shaft wall on the cause of the breakdown of the coal mine shaft wall rupture theory analysis of a serious impact on mine safety, coal mine shaft wall rupture mechanism as mining, geology, industry-related experts in the field the focus of debate . Past 20 years, especially since the 1990s, domestic mining and geological industry experts and scholars on the mine shaft wall rupture causes a lot of research and scientific experiments can be broadly grouped into six categories: (1) to be mechanical (including earthquake damage, said that the tectonic remote). (2) the quality of construction,######## oakley sunglasses, said. (3) seepage deformation said. (4) study of negative friction. (5) (6) vertical wall, said additional stress.

4 mine shaft wall on the cause of the breakdown of discussions in a number of theoretical reasons after a heated discussion. After many years of proven: the main mine shaft wall rupture more likely to cause additional stress, said vertical wall. Bottom wall rupture due to falling water tables, aquifers drain,true religion outlet, resulting in the formation of effective stress to increase, so the consolidation of the strata around the sink wall, wall located in the bedrock due to not sink together with the Quaternary, the wall, the inside of the mutual movement between the downward pull of the wall --- a negative friction, this force in the bottom half of the largest aquifer in the vicinity, and the maximum wall force in the vicinity of the weakest stress can easily exceed its yield strength, and because of melting permafrost in the wall of weeks, resulting in the formation of liquefied and easily to the upper part of the water layer and the bottom of the aquifer water connected; the end gravel drainage layer, it is easy to make his entire ground drainage caused by soil consolidation settlement. Thus, the melting of frozen ground in a way to increase the drainage and consolidation settlement of formation; due to temperature rise in a side wall leaving the holding force generated when the vertical stress, with the superposition of the negative friction resulting in stress , increasing the Quaternary and bedrock at the junction of wall deterioration within the state of stress. It follows that the drainage from the bottom of the aquifer strata consolidation of the wall around the sink have a negative wall friction is caused by damage to the main wall. The melting of frozen ground so the bottom of the aquifer and the upper hydraulic connection of aquifers and the wall temperatures to produce compressive stress is increased wall damage two reasons. Therefore, additional wall stress that the interpretation of the wall rupture is more realistic, therefore, particularly in the choice of reinforcing material formation is especially important.
CLC number: TD352 Text Search: B :1009 -0797 (2010 ) 03-0116-03



summary analysis of coal in China's energy framework in an important position, that the coal in the mining process of personnel safety. Set mine shaft wall rupture and polymer materials science and technology and polymer materials combine performance, increase the safety factor of coal production, to increase coal efficiency.

5 mine shaft wall rupture and seepage grouting technology is often associated with coal mine shaft wall rupture wall seepage, gushing water and rock wall surrounding the complexities of water loss compression, it is easy not to govern caused by sudden water, sand and sudden accidents, as well as solve the water layer between the upper and lower wall resulting from additional stress, etc., grouting is used to reinforce the importance of formation technology, which includes plugging, closure, curtain and rock reinforcement, etc. multi-technology group.

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