外文翻译-煤与瓦斯突出控制技术在高瓦斯煤层快速掘进中的应用.doc

1、翻译部分英文原文Outburst control technology for rapid excavation in severe outburst coalQU Yang（ Department of Mining Engineering, Henan Engineering Technical School, Jiaozuo 454000, China ）Abstract: The advantages and disadvantages of various outburst prevention measures in heading face were analyzed. The

2、mechanism of outburst prevention about hydraulic extrusion measure was studied, the technological parameters were introduced, and the effect of outburst prevention was investigated. The in-situ experimental results show that the hydraulic extrusion measures are applied in serious outburst mine, not

3、only the stress of stimulate outburst is eliminated effectively but also the gas in coal seam is released efficiently, the measures get obvious effect on coal and gas outburst prevention, and the roadway driving speed is increased by 1.5 times, implementing a safe and rapid excavation.Keywords: mech

4、anism of outburst prevention, outburst prevention measure, rapid excavation, hydraulic extrusion, water injectionIntroductionCoal and gas outburst is one of the most serious natural disasters in coal mine exploitation and is a complex dynamic phenomenon. According to the statistics of working place

5、where coal and gas outburst occurred （Yu, 1992）, a great number of outburst accidents occurred at the heading face of coal roadway, taking up 66.2% of all outburst accidents, and the average outburst intensity was 66.9 t. When driving in coal roadway with severe outburst potential danger, gas emissi

6、on is great, the situation shall become serious as gas concentration exceeds the standard, and the driving speed is affected so greatly in coal roadway that the average driving speed is only 35 m each month in countrywide outburst mines. The speed of driving is so slow that it affects the normal rep

7、lacement between coal-driving and cutting. This situation consequently makes the time needed for gas drainage turn out to be short. A vicious circle starts when the gas drainage rate is practically low, which brings new potential danger to mines.In order to prevent coal and gas outburst efficiently

8、in coal roadway, some outburst prevention measures are adopted, such as the measure of shallow loose explosion, advanced discharge orifice, deep borehole control blasting, hydraulic flushing, etc. （Bo, 2000; Liu and Shi, 2002; He, 2004; Liu et al., 2005）. A definite effect of outburst prevention has

9、 been achieved; nevertheless, they have respective disadvantages of safety and the slow driving speed. For example, shallow loose explosion is applied in coal seam whose anthrax is hard and outburst intensity is weak; it may induce outburst in severe outburst coal. The measuring time of advanced dis

10、charge orifice is long, and effective function region of its borehole is small, its repetition rate is high, and it may also induce coal and gas outburst in severe outburst coal. Deep borehole control blasting, because the technology of explosives filling is not essentially settled, and the technolo

11、gy of operation is complex and not available. Hydraulic flushing is mainly used to excavate rock crosscut or driving in coal seams whose flowing ability is strong. So, we need to research for new measures of outburst prevention to improve the driving speed under the safe circumstance.Hydraulic extru

12、sion is a safe measure compared with other measures, its technology is easy, and the effect of outburst prevention is obvious. This technology was applied at Liyi Coal Mine in Huainan Mining Industrial （Group） Co., Ltd. The driving speed reached 100 m each month and got good economic benefits.1 Basi

13、c situationThe test roadway is a return airway of -610 m W2EB8 working face. It is at the east of the second mine section. The height mark of tunnel is -612 m; its designed length is 450 m. The roadway is supported by anchor net and anchor wire; its basal area is 11.2 m2. The thickness of B8 coal se

14、am at this area is 3.0 m to 4.0 m, the coal seam strike is 140 to 160, and the rake angle is 20 to 25. The immediate roof of coal seam is grayish white sand rock, and its thickness is 4.0 m to 6.0 m. The lamination of rock stratum develops well. The floor of coal seam is compact shale and gray, and

15、its thickness is 4.0 m to 6.0 m. This working face is at the bottom of F13-8-2 fracture, be-cause it is affected by this fracture. small derivative constitution develops, and the coal strike and inclination change greatly near the fracture; the thickness of coal seam changes. Because of small consti

16、tution and high gas content, the region has serious outburst potential. Since the roadway was exploited, advanced discharge orifice and joint excavation and gas drainage had been used, although, getting some effectiveness, validity checking and gas concentration often exceed the standard. The speed of driving is slow, and the average speed is less than 40 m each month; it affects the normal replacement between coal-driving and cutting. Therefore, we need a