外文翻譯---采動(dòng)對(duì)工作面內(nèi)瓦斯釋放的影響

1、<p><b>　　翻譯部分</b></p><p><b>　　英文原文：</b></p><p>　　INFLUENCE OF TREMORS INDUCED BY MINING ON THE LIBERATION OF METHANE IN TO WORKINGS</p><p>　　Krzysz

2、tof OGIEG?O, Mieczys?aw LUBRYKA, Jan KUTKOWSKI</p><p>　　?Jas-Mos” Coal Mine, Jastrz?bie Zdrój</p><p>　　Józef SU?KOWSKI, The Silesian University of Technology, Gliwice, Poland</p>

3、;<p><b>　　Abstract</b></p><p>　　Methane which appears in the workings comes from excavated coal, side walls, free faces and from basins in the surrounding rock mass such as adjoining coal

4、 beds and Weber goafs. Liberation of methane takes place through fissures and through porous and easily permeable rock layers.</p><p>　　Simultaneous overlapping of the influences of mining fronts leads to in

5、crease in liberation of methane as a result of appearance of rock mass distressing. Coal bed mining at deeper level induces also tremors which can be followed by cracking of rock layers situated either in the close neigh

6、bourhood or in a distance from the workings. The existed fissures i.e. fault fissures and those connected with the prior loosening of the roof layers or floor layers while mining the coal bed.</p><p>　　Sever

7、al examples from the practise of mining prove that there is relation between the occurrence of increased methane hazard in the workings and the energy of mining tremor, as well as horizontal distance of the evaluated tre

8、mor focal point.</p><p>　　Tremor can be the cause of intensified liberation of methane into the workings and increase of methane concentration in the mine air exceeding the acceptable value if ventilation pa

9、rameters are not readjusted to the amount of the methane outflow.</p><p>　　Confirmed association of methane and tremor hazards justify the need of proper prevention in order to eliminate disturbance in venti

10、lation of workings.</p><p>　　1.Introduction</p><p>　　Association of natural hazards in the past was searched mainly considering the following systems:</p><p>　　-mining tremor – ro

11、ck bump</p><p>　　-rock bump – methane liberation – coal dust explosion</p><p>　　-rock bump – spontaneous fire</p><p>　　-methane explosion – coal dust explosion.</p><p&

12、gt;　　At the beginning of the 90’s the attention was also drawn to the system of mining tremor – methane liberation type [4]. The co-occurrence of such system of hazards had also taken place before, but there was no data

13、 about their number, frequency or range. This paper is a result of a few years’ observation of cases when sudden increase in methane concentration appears in the seams with seismic activity, after mining tremors. The obs

14、ervation focused on searching causal connections between sudden i</p><p>　　The influence of mine tremor energy on methane emission into the mine working</p><p>　　The registered parameter which c

15、haracterises scale of the tremor is its energy. During the seam mining the quantity of the released energy depends mainly on:</p><p>　　-seam or mining port thickness</p><p>　　-way of roof cont

16、rol</p><p>　　-speed of mining.</p><p>　　The sum of energy revealed from the rocks increases with the depth of mining, but the size of portions of revealing is also important [2]. In the observe

17、d mines low-energy tremors were connected with rock mass cracking in the close neighbourhood of workings. Focal points of the tremors occurred near working front and moved with it. Focal points of high-energy tremors of

18、106-107J occurred, in most cases, in significant distance from mining front and were connected mainly with the geological disco</p><p>　　The average growth in methane concentration after tremors of different

19、 energy is presented in Figure 1. In the figure, methane content of seams where the mining took place, is also differentiated. Part of the results was obtained from the seams included in II category (2,5 ÷4,5 m3CH4/

20、Mg) and the rest from the seams of IV category (above 8 m3CH4/Mg).</p><p>　　As Figure 1 shows, in the interval of 102 – 105J tremor energy does not influence the amount of increase of methane concentration i

21、n the nearby workings.</p><p>　　Fig.1Influence of tremor energy on average increase in methane concentration in the nearby workings</p><p>　　3.The influence of the place of mine tremor occurre

22、nce on increase in methane concentration in workings in the observed area</p><p>　　The results of mine tremors observation on the selected seams enabled to evaluate the influence of the horizontal distance o

23、f tremor focal point on the increase in methane concentration in driven longwalls and roadheads. The greatest number of mine tremors which caused increase in methane concentration in the working faces were those, with fo

24、cal points located near the mine face. The range of influence of the mine tremor focal point location on the increase in methane concentration in longwall f</p><p>　　However, the range of influence of tremor

25、s located in goafs on increase in methane concentration in working faces reached 30 m – outside that distance the influence of the </p><p>　　tremor disappeared totally. The influence of the horizontal distan

26、ce of tremor focus from the total length of faces on increase in methane concentration in the longwall faces is shown in Figure 2. </p><p>　　In the headings the range of the tremor influence on increase in

27、methane concentration reached up to 60 m in the radius from the heading face or heading wall.</p><p>　　It should be also mentioned that determining the exact place of the tremor focal point is extremely diff

28、icult because focal points are also of different size. For example, according to the research the tremor with energy of E=106J has the focal point of range 150÷200 m, so it is comparable with the length of longwall

29、face [1].</p><p><b>　　Example 1</b></p><p>　　In the seam 703, in the face M-6, mine tremor with energy of 1,4x106J took place. It happened at 9.27pm on 24.11.97. The focal point was

30、located 170m before the longwall front and 30m from the face heading. The tremor of so big energy caused small increase in methane concentration, whereas the tremor with energy of 5,3x103J which occurred on 11.12.97 at 5

31、.20 am, with focal point located over the longwall front, caused increase in methane concentration that exceeded the initial value by 9 times, </p><p>　　Fig. 3.Example of methane emission into the longwall

32、face after the occurrence of two tremors of different energy and focal points location</p><p>　　Fig. 4.Example of methane emission into the longwall face after the tremor near the fault and close to the l

33、ongwall front</p><p><b>　　Example 2</b></p><p>　　The longwall face in the seam 510 was driven with the roof stowing. The tremor occurred at the end of the longwall run, when its fron

34、t was coming closer to the downthrow, with the throw from 0,8 to 2,5m (which was the boundary of mining). The energy of the tremor was 6,6x104J (Fig.4). It happened at 4.55am on 28.05.1991. The focal point was located ne

35、ar the downthrow, about 30m before the longwall face. At 5.08am sudden increase of methane concentration appeared. It was from 0.3% to the value of</p><p>　　4.The influence of number of tremors on the incre

36、ase in methane condensation in longwalls</p><p>　　Monitoring and analysing the number of tremors during the period of one month showed their influence on increase in methane concentration in the workings(Fig

37、.6). It was noticed that in the seams of the IV category of methane hazard, in the longwall faces driven with stowing, in the seams of the IV category of methane hazard, increase in methane concentration appeared when th

38、e number of tremors was about 25 per month. In the longwall faces driven with roof fall, increase in methane concentration </p><p>　　Fig.5.Influence of number of tremors recorded during a month in seams of

39、 II and IV category of methane hazard, on the frequency of increase in methane concentration</p><p>　　The biggest, exceeding even 5%, increase in methane concentration after the occurred tremors, took place

40、when the number of tremors ranged from 100 –150 per month.</p><p>　　When there was more than 150 bumps per month, increase in methane concentration only in some cases exceeded slightly the highest permissibl

41、e concentration, and when there was more than 200 bumps per month, the difference in methane concentration before and after the tremor was very little.</p><p>　　In the seams of the II category of methane haz

42、ard, some cases of increase in methane concentration occurred in the longwalls, when the number of tremors was 50÷100 per month, and they disappeared at number of about 250 tremors per month. The biggest increase in

43、 methane concentration in the longwalls occurred when the number of tremors was 150 – 200 per month.</p><p>　　5.The influence of mining speed on the number of tremors and increase in methane concentration i

44、n the working</p><p>　　Increase in mining speed causes increase in the emission of seismic energy, released from the rock mass, and increase in number of tremors, which may be the cause of increased growth i

45、n methane concentration after the occurred tremors [3]. However, the results of the analysis, carried out for a dozen or so of longwalls, show that the influence can be more complex.</p><p>　　It was noticed,

46、 that in the monitored seams growth of mining front speed from 1m/day to 5m/day caused increase of number of tremors from 50 to 140 per month (Fig.7). Increased number of tremors during a month resulted in increased numb

47、er of cases of methane condensation growth and in increased average value of condensation growth after the occurred mine tremors, but only at the speed up to 1÷2 m/day. At the speed from 3m/day to 5 m/day, the avera

48、ge growth of methane condensation after the occurr</p><p>　　When the speed was over 5m/day the number of tremors increased rapidly, exceeding 200 per month, but there was decrease of the average value of met

49、hane condensation.</p><p>　　Fig.6.The influence of mining speed on the number of tremors and on average increasein methane condensation obtained for the data from a dozen or so longwalls.</p><p&

50、gt;　　Mining of seam 703 can be given as an example of relations between all the above-mentioned factors. During the mining speed was successively increased (Fig. 8). It caused rapid growth in number of tremors from 60 to

51、 230 per month. At the same time there were cases of methane emission after the tremors. The average value of increase in methane condensation was the highest at the mining speed of 4÷5 m/day. Speed growth over 5m/d

52、ay also caused methane emission, but it was recorded as smaller increa</p><p>　　The occurring high-energy tremors, bigger than E=105J, caused stoppages of the longwall face. The stoppages happened on average

53、 twice a week, so after careful consideration, the face advance was limited to about 2÷4 m/day.</p><p>　　After the month of mining, it appeared, that the number of tremors dropped to about 50 per month,

54、 and the average increase in methane concentration after its liberation following the tremors, also dropped to the value of 0,1%.</p><p>　　Fig.7.The influence of changeable mining speed in the one longwall

55、on the number of tremors and on average increase in methane condensation</p><p>　　6.The influence of methane content of the seam on the increase in methane concentration after the occurred tremors</p>

56、;<p>　　Methane content of the seam was of great importance in the considered examples of stated growths of methane concentration in the air after the occurred tremor. Even in the seams in which methane drainage wa

57、s conducted because methane content of the seam exceeded 8 m3/Mgc.s.w., after the occurred tremors, some cases of increase in methane concentration over 5% were noticed. Quantity of the increase of methane concentration

58、after the occurred tremors, was bigger when mining took place near geologi</p><p>　　Fig.8.The influence of methane content on the quantity of average increase in methane concentration</p><p>　

59、　7.Conclusions</p><p>　　Rock mass tremors with energy of 103J -105J did not cause varied growths in methane concentration in the workings which are subject to their influence, so they were similar to the am

60、ount of the flowing in methane. High-energy tremors 106J –107J, affected increase in methane concentration mainly indirectly ( fall of coal walls and roof layers).</p><p>　　The influence of the distance of

61、focal point of tremor from the line of mining on the growth of methane concentration is clear and depends on mining-and-geological conditions. The zone of the mining tremor influence on the growth in methane concentratio

62、n reached 60m in front of and 30m behind the mining line for the heading faces within the radius of 60m round the working.</p><p>　　The biggest growths in methane concentration occurred after rock mass tremo

63、rs, when focal points were located about 30m before and after the mining line.</p><p>　　Frequency of the tremors affected the appearance of the fissures or the propagation of the existed ones, which are the

64、way of methane migration into the mine workings. The biggest growths in methane concentration after the occurred tremors were observed when the number of the tremors was 100÷150 in a month in seams of IV category of

65、 methane hazard, and 150÷200 tremors in a month in seams of II category. When the number of tremors in a month was bigger, the observed growths in methane increase in</p><p>　　Speed of mining affects di

66、rectly the occurrence of bigger number of tremors and then the fissures. Therefore, speed of mining is an important factor which influences the appearance of sudden growths in methane concentration after the mining tremo

67、rs, because it affects the number of tremors.</p><p>　　Also methane content of the seam influences clearly the amount of the growth in methane concentration after the tremors. In the seams of IV category of

68、methane hazard, after the tremors, the average amount of methane concentration growths was 100% bigger than in the II category of methane hazard.</p><p>　　References</p><p>　　Drz??la B., Dubińsk

69、i J.: Lokalizacja ognisk wstrz?sów górniczych. Szko?a Eksploatacji Podziemnej, 1995, Wyd. CPPGSMiE PAN, Kraków.</p><p>　　Goszcz A.: Elementy mechaniki ska? oraz t?pania w polskich kopalniach w

70、?gla i miedzi. Biblioteka Szko?y Eksploatacji Podziemnej, Kraków 1999.</p><p>　　Konopko W?., Kabiesz J.: Pr?dko?? post?pu frontu ?cianowego a zagro?enie t?paniami i metanem. Szko?a Eksploatacj

71、i Podziemnej, 1996, Wyd. CPPGSMiE PAN, Kraków.</p><p>　　Konopko W., Kabiesz J., Cygankiewicz J.: Wstrz?sy i t?pania jako inicjatory zagro?enia metanowego. Przegl?d Górniczy nr 2, 1994.</p>&

72、lt;p>　　Kutkowski J., Badura H.: Wp?yw wstrz?sów sejsmicznych na zagro?enie metanowe. Przegl?d Górniczy nr 3, 1998.</p><p>　　Kutkowski J.: Wp?yw rejonizacji, ogniska wstrz?su i jego energii na pr

73、zyrost st??enia metanu w wyrobiskach prowadzonych w jego s?siedztwie. Przegl?d Górniczy nr 4, 1999.</p><p>　　Ogieg?o K.,Skatu?a R., Kutkowski J.: Wyp?yw metanu do wyrobisk górniczych jako prekursor

74、 wstrz?su górniczego. VII Konferencja Naukowo-Techniczna T?PANIA 2000, Katowice, 15-17 listopad 2000.</p><p>　　Ogieg?o K., Lubryka M., Skatu?a R., Kutkowski J.: Wydzielanie si? metanu pod wp?ywem wstrz?

75、sów górniczych. Wieliczka, Warsztaty 2001. </p><p>　　采動(dòng)對(duì)工作面內(nèi)瓦斯釋放的影響</p><p>　　Krzysztof OGIEG?O, Mieczys?aw LUBRYKA, Jan KUTKOWSKI</p><p>　　?Jas-Mos” Coal Mine, Jastrz?bie

76、Zdrój</p><p>　　Józef SU?KOWSKI, The Silesian University of Technology, Gliwice, Poland</p><p><b>　　摘要</b></p><p>　　煤礦開(kāi)采中的瓦斯來(lái)自于采下的煤、巷道的兩壁、自由工作面、相鄰煤層和采空區(qū)的碎矸當(dāng)中。裂

77、隙以及多孔易滲透的巖層當(dāng)中易發(fā)生瓦斯的溢出。工作面前方，由于采動(dòng)和巖體破壞的綜合影響將使瓦斯的釋放量增加。深部開(kāi)采時(shí)，容易引起震動(dòng)，并且與工作面相臨的或間隔一定距離的巖層也隨之遭到破壞。產(chǎn)生的裂隙包括斷層裂隙和與開(kāi)采過(guò)程中預(yù)先松動(dòng)頂板或地板有關(guān)的裂隙。開(kāi)采實(shí)踐中的幾個(gè)例子證明，工作面內(nèi)瓦斯?jié)舛鹊脑黾优c震動(dòng)的能量有關(guān)，就象震動(dòng)的能量與震動(dòng)傳播的距離有關(guān)一樣。震動(dòng)是工作面內(nèi)瓦斯?jié)舛仍黾拥脑颍绻徽{(diào)整瓦斯的溢出量，將引起工作面內(nèi)空氣中瓦斯

78、濃度超過(guò)容許值。瓦斯與震動(dòng)間的必然聯(lián)系要求我們采取真確的預(yù)防措施以改善工作面的通風(fēng)狀況。</p><p><b>　　前言</b></p><p>　　過(guò)去在研究自然災(zāi)害之間的關(guān)系時(shí)主要考慮以下幾個(gè)方面：</p><p><b>　　采動(dòng)——巖石突出</b></p><p>　　巖石突出——瓦斯突出

79、</p><p>　　巖石突出——煤層自燃發(fā)火</p><p>　　瓦斯爆炸——煤塵爆炸</p><p>　　90年代初，人們主要研究采動(dòng)與瓦斯釋放類型之間的規(guī)律。雖然這在以前也曾研究過(guò)，但并沒(méi)有數(shù)據(jù)記錄它們發(fā)生的次數(shù)、頻率和范圍。采動(dòng)之后隨著震動(dòng)的產(chǎn)生，將引起煤層中瓦斯?jié)舛鹊耐蝗辉黾?，本文就是介紹對(duì)這種現(xiàn)象多年研究的結(jié)果，研究旨在找出震動(dòng)和震動(dòng)剛發(fā)生后工作面內(nèi)空氣

80、中瓦斯?jié)舛韧蝗辉龃笾g的關(guān)系，尤其是它們的數(shù)量關(guān)系。為此，我們?cè)赗ybnik礦（Coal Basin of Rybnik）觀察了約5500次震動(dòng)，震動(dòng)的能量從103J到107J不等，它們分別發(fā)生在12個(gè)長(zhǎng)壁跨落采煤工作面和8個(gè)巷道掘進(jìn)頭處 。除震動(dòng)能量之外，也同時(shí)考慮了震源的水平位置、煤層開(kāi)采速度、煤層瓦斯含量以及震動(dòng)的次數(shù)等。通過(guò)分析工作面內(nèi)瓦斯?jié)舛鹊脑黾优c上述參數(shù)之間的關(guān)系將為采取正確的措施以防止震動(dòng)后瓦斯突出帶來(lái)危險(xiǎn)的后果指明方向

81、。震動(dòng)后瓦斯突出是采煤工作面周?chē)鷰r體破壞的結(jié)果。根據(jù)壓力大小的梯度，擴(kuò)張或擠壓裂隙將使其中的瓦斯釋放到工作面。觀測(cè)資料已經(jīng)表明，在一些情況下，瓦斯突出發(fā)生在震動(dòng)之前，上述情況的出現(xiàn)是煤層開(kāi)采過(guò)程中巖體變形的結(jié)果，并且在開(kāi)采后期由于瓦斯的釋放將導(dǎo)致震動(dòng)的產(chǎn)生。</p><p>　　震動(dòng)能量對(duì)工作面內(nèi)瓦斯?jié)舛鹊挠绊?lt;/p><p>　　震動(dòng)能量是表證震動(dòng)強(qiáng)度大小的參數(shù)。開(kāi)采過(guò)程中釋放能量的大小

82、主要取決于：</p><p>　　煤層或開(kāi)采煤層的厚度</p><p><b>　　頂板控制方法</b></p><p><b>　　開(kāi)采速度</b></p><p>　　巖石中釋放的總能量隨開(kāi)采深度的增大而增加，但是釋放的部分能量的大小也同樣重要，在所觀測(cè)的礦井中，低能量的震動(dòng)與工作面周?chē)鷰r體的破

83、碎度有關(guān)。在很多情況下，能量為106J到107J的震動(dòng)，其震源距工作面的距離主要與地質(zhì)構(gòu)造的不連續(xù)性有關(guān)。因此很難找出高能量的震動(dòng)與瓦斯突出之間的直接關(guān)系。然而，低能量的震動(dòng)先于瓦斯突出而發(fā)生，這從工作面內(nèi)瓦斯?jié)舛鹊脑黾又锌梢缘玫阶C明。在所監(jiān)測(cè)的震動(dòng)當(dāng)中，有10—15%發(fā)生過(guò)這種情況。在震動(dòng)之前，瓦斯釋放將導(dǎo)致工作面內(nèi)瓦斯?jié)舛戎辽僭黾?%，但在很多情況下，震動(dòng)并不能引起瓦斯釋放。不同能量的震動(dòng)引起的瓦斯?jié)舛鹊钠骄黾又狄?jiàn)表1。表1當(dāng)中的

84、部分結(jié)論是從二級(jí)瓦斯煤層中得到的。正如表1所示，能量在102J到105J的震動(dòng)不會(huì)影響到附近工作面內(nèi)瓦斯的濃度。</p><p>　　圖1. 震動(dòng)對(duì)鄰近工作面內(nèi)瓦斯含量的影響</p><p>　　震動(dòng)中心的位置對(duì)工作面內(nèi)瓦斯?jié)舛鹊挠绊?lt;/p><p>　　通過(guò)對(duì)煤層觀測(cè)的結(jié)果可以估計(jì)震動(dòng)中心到工作面和巷道掘進(jìn)頭的距離對(duì)瓦斯?jié)舛鹊挠绊?。在引起工作面?nèi)瓦斯?jié)舛仍黾拥恼饎?dòng)

85、當(dāng)中，其震動(dòng)中心鄰近工作面的震動(dòng)最多。在長(zhǎng)壁工作面中，震動(dòng)中心對(duì)瓦斯?jié)舛仍黾拥挠绊憣⑦_(dá)到工作面前方約60—70米處，并且在很大程度上取決于開(kāi)采條件和地質(zhì)條件（如落差、邊界等）。引起瓦斯?jié)舛仍黾幼畲蟮恼饎?dòng)，其震動(dòng)中心位于工作面30米以內(nèi)的地方。然而，位于采空區(qū)的震動(dòng)，由于其震動(dòng)中心距工作面的距離已超過(guò)30米，故其對(duì)瓦斯?jié)舛鹊淖兓瘞缀鯖](méi)有影響，震源距工作面的距離對(duì)瓦斯?jié)舛鹊挠绊懸?jiàn)表2。</p><p>　　在巷道當(dāng)中

86、，震源對(duì)瓦斯?jié)舛鹊挠绊懛秶鷮⑦_(dá)到距掘進(jìn)頭或巷道壁60米的地方。</p><p>　　圖2. 震源與工作面之間的距離對(duì)工作面內(nèi)瓦斯?jié)舛扔绊懙囊罁?jù)。</p><p>　　應(yīng)該提一下，確定震源的確切位置并非易事，因?yàn)樗某叽缡亲兓摹?jù)研究發(fā)現(xiàn)，能量為106J的震動(dòng)，其震源的大小為150—200米，因此，它的尺寸和工作面的長(zhǎng)度相當(dāng)。</p><p><b>　　

87、例1</b></p><p>　　97年11月24日晚9點(diǎn)27分，在703煤層的M—6號(hào)工作面發(fā)生了能量為1.4*106J的震動(dòng)，震動(dòng)中心在工作面前方170米、巷道掘進(jìn)頭30米處，能量如此大的震動(dòng)僅僅使瓦斯?jié)舛壬晕⒃黾??？墒?7年12月11日早晨5點(diǎn)20分發(fā)生的震動(dòng)，雖然能量只有5.3*103J，但由于其震源位于工作面上方，故引起的瓦斯?jié)舛瘸^(guò)平常值的9倍之多。以上情況的發(fā)生不是孤立的，它證明了這樣一

88、個(gè)觀點(diǎn)，那就是，決定瓦斯涌出量大小的不是震動(dòng)的能量而是震源的位置。</p><p>　　圖3 能量和震源不同的震動(dòng)發(fā)生后，工作面內(nèi)瓦斯涌出的例子。</p><p>　　圖4 斷層和工作面附近震動(dòng)發(fā)生后瓦斯涌出的例子。</p><p><b>　　例2</b></p><p>　　510煤層采用長(zhǎng)壁充填法開(kāi)采，開(kāi)采邊界

89、是一條0.5米到2.5米的斷層，在開(kāi)采后期，當(dāng)推進(jìn)到斷層的下降盤(pán)時(shí)，發(fā)生了震動(dòng)。這次震動(dòng)的能量為6.6*104J（表4），發(fā)生在1991年5月28日早晨4點(diǎn)55分，震源在斷層附近、工作面前方約30米處，到5點(diǎn)08分，瓦斯?jié)舛韧蝗患眲∩仙瑤追昼娭?，已?jīng)從原來(lái)的0.3%增加到5%之多。并且一直持續(xù)到6點(diǎn)50分，然后急劇下降。到7點(diǎn)10分達(dá)到0.3%。瓦斯?jié)舛乳L(zhǎng)時(shí)間超過(guò)5%，在很大程度上是因?yàn)檎鹪次挥跀鄬拥南陆当P(pán)，而斷層的下降盤(pán)則象一個(gè)收

90、集器，將裂隙中大量的瓦斯聚集起來(lái)。</p><p>　　4.震動(dòng)次數(shù)對(duì)長(zhǎng)壁工作面內(nèi)瓦斯?jié)舛鹊挠绊?lt;/p><p>　　通過(guò)監(jiān)測(cè)和分析一個(gè)月內(nèi)震動(dòng)發(fā)生的次數(shù)可以找出它們對(duì)工作面內(nèi)瓦斯?jié)舛仍黾拥挠绊懀ㄈ绫?），可以看出，在四級(jí)瓦斯煤層中和長(zhǎng)壁工作面內(nèi)，當(dāng)每月的震動(dòng)數(shù)為25次時(shí)，瓦斯?jié)舛葘?huì)上升，在跨落長(zhǎng)壁工作面內(nèi)，當(dāng)每月震動(dòng)次數(shù)超過(guò)20—50次時(shí)，瓦斯?jié)舛纫矔?huì)上升；當(dāng)巖石突出次數(shù)每月超過(guò)100

91、—150次時(shí)，震動(dòng)后瓦斯?jié)舛鹊脑黾又捣炊_(kāi)始減少；當(dāng)超過(guò)250次時(shí)，瓦斯?jié)舛葞缀醪辉僭黾印?lt;/p><p>　　圖5 二級(jí)和四級(jí)瓦斯煤層中每月震動(dòng)的次數(shù)對(duì)瓦斯?jié)舛仍黾拥挠绊?lt;/p><p>　　四級(jí)瓦斯煤層中，當(dāng)每月的震動(dòng)次數(shù)在100—150之間時(shí)，瓦斯?jié)舛仍黾拥淖畲?，甚至超過(guò)5%；當(dāng)每月的巖石突出次數(shù)超過(guò)150次時(shí)，瓦斯?jié)舛戎粫?huì)稍微超出最高允許濃度，當(dāng)每月突出次數(shù)多于200次時(shí)，震前震

92、后的瓦斯?jié)舛葞缀跸嗖顭o(wú)幾。</p><p>　　二級(jí)瓦斯煤層中，一些情況下，當(dāng)每月震動(dòng)次數(shù)為50—100時(shí)，工作面內(nèi)瓦斯?jié)舛葧?huì)增加；當(dāng)震動(dòng)次數(shù)為250此時(shí)，瓦斯?jié)舛炔辉僭黾?；?dāng)每月震動(dòng)150—200次時(shí)，工作面內(nèi)瓦斯?jié)舛鹊脑黾又底畲蟆?lt;/p><p>　　5. 開(kāi)采速度對(duì)工作面內(nèi)震動(dòng)次數(shù)和瓦斯?jié)舛鹊挠绊?lt;/p><p>　　增大開(kāi)采速度可以使巖體中釋放的震動(dòng)能量增加

93、、使震動(dòng)次數(shù)增加，繼而有可能使瓦斯?jié)舛仍黾?，但是通過(guò)對(duì)約20個(gè)工作面研究的結(jié)果分析可知，其影響可能要更加復(fù)雜一些。</p><p>　　我們注意到，在所觀測(cè)的煤層中，當(dāng)開(kāi)采速度從1米/天增加到5米/天時(shí)，震動(dòng)次數(shù)從每月50次增加到140次（表7）。一個(gè)月當(dāng)中震動(dòng)次數(shù)的增加將導(dǎo)致瓦斯?jié)舛仍黾铀俣燃涌?，但這僅限于開(kāi)采速度為1—2米/天時(shí)；當(dāng)開(kāi)采速度為3—5米/天時(shí)，瓦斯?jié)舛仍黾铀俣确炊鴾p小；當(dāng)開(kāi)采速度超過(guò)5米/天時(shí)，

94、震動(dòng)次數(shù)繼續(xù)增加，甚至超過(guò)200次/月，但是瓦斯?jié)舛鹊钠骄鲩L(zhǎng)值卻在減小。 </p><p>　　圖6 從大約20個(gè)長(zhǎng)壁工作面中得到的關(guān)于開(kāi)采速度對(duì)震動(dòng)次數(shù)和瓦斯?jié)舛绕骄鲩L(zhǎng)值影響的數(shù)據(jù)。</p><p>　　將703煤層的工作面作為一個(gè)例子來(lái)說(shuō)明以上所述因素之間的關(guān)系。在開(kāi)采過(guò)程中，開(kāi)采速度是連續(xù)增加的（表8），由此引起的震動(dòng)次數(shù)快速增加，從每月60次增加到230次，同時(shí)在震動(dòng)之后有瓦

95、斯涌出。當(dāng)開(kāi)采速度為4—5米/天時(shí)，瓦斯?jié)舛鹊钠骄鲩L(zhǎng)值達(dá)到最大，當(dāng)開(kāi)采速度超過(guò)5米/天時(shí)，也能引起瓦斯釋放，但是工作面內(nèi)瓦斯?jié)舛仍黾恿亢苌?。高能量的震?dòng)，如能量超過(guò)105J，可使工作面停產(chǎn)。當(dāng)一星期停產(chǎn)2次時(shí)，就應(yīng)該考慮將工作面推進(jìn)速度限制在2—4米/天。</p><p>　　開(kāi)采1個(gè)月后，震動(dòng)次數(shù)減少到每月50次左右，并且震動(dòng)后瓦斯?jié)舛绕骄狄矞p小到0.1%。</p><p>　　圖7

96、 改變工作面推進(jìn)速度對(duì)震動(dòng)次數(shù)和瓦斯?jié)舛绕骄鲩L(zhǎng)值的影響。</p><p>　　6．煤層瓦斯含量對(duì)震動(dòng)后瓦斯?jié)舛仍黾拥挠绊?lt;/p><p>　　震動(dòng)發(fā)生后，煤層瓦斯含量對(duì)空氣中瓦斯?jié)舛鹊姆€(wěn)定增長(zhǎng)影響非常大。在一些煤層中，雖然瓦斯已經(jīng)被部分排出，但由于其瓦斯含量超過(guò)8m3/t,所以震動(dòng)發(fā)生后，在有些情況下，依然可以觀察到瓦斯?jié)舛瘸^(guò)5%，當(dāng)開(kāi)采到地質(zhì)構(gòu)造不連續(xù)區(qū)時(shí)，震動(dòng)后瓦斯?jié)舛鹊脑鲩L(zhǎng)值將

97、會(huì)變大。表9列出了當(dāng)震動(dòng)發(fā)生后，煤層瓦斯含量對(duì)工作面內(nèi)瓦斯?jié)舛绕骄黾又档挠绊憽?lt;/p><p>　　圖8 煤層瓦斯含量對(duì)瓦斯?jié)舛绕骄鲩L(zhǎng)值的影響</p><p><b>　　7．結(jié)論</b></p><p>　　瓦斯?jié)舛仁軒r體震動(dòng)的影響，能量為103J—105J的震動(dòng)不會(huì)使瓦斯?jié)舛鹊脑黾又底兓?；能量?06J—107J的震動(dòng)能間接地引起瓦

98、斯?jié)舛鹊脑黾?。震源距工作面的距離取決于開(kāi)采條件和地質(zhì)條件，并且對(duì)瓦斯?jié)舛鹊挠绊懯秋@而易見(jiàn)的，它能影響到工作面前方60米、后方30米和掘進(jìn)頭60米以內(nèi)區(qū)域的瓦斯?jié)舛取?lt;/p><p>　　當(dāng)震源在工作面前方和后方30米處時(shí)，巖體突出后，瓦斯?jié)舛仍黾又底畲蟆?lt;/p><p>　　震動(dòng)的頻率能影響裂隙的產(chǎn)生或已有裂隙的延伸和傳播，而瓦斯正是從這些裂隙當(dāng)中溢出而涌入工作面的。當(dāng)四級(jí)瓦斯煤層每月震動(dòng)

99、100—150次、二級(jí)瓦斯煤層每月震動(dòng)150—200次時(shí)，瓦斯?jié)舛仍黾又底畲?，?dāng)震動(dòng)次數(shù)再增加時(shí)，瓦斯?jié)舛仍黾拥梅炊幻黠@。</p><p>　　開(kāi)采速度直接影響震動(dòng)發(fā)生的次數(shù)繼而影響到裂隙的產(chǎn)生，故它是瓦斯?jié)舛韧蝗辉龃蟮囊粋€(gè)非常重要的影響因素。</p><p>　　煤層瓦斯含量也明顯地影響瓦斯?jié)舛鹊卦黾樱?dāng)震動(dòng)發(fā)生后，四級(jí)瓦斯煤層中的瓦斯?jié)舛仍黾又凳嵌?jí)瓦斯煤層的2倍。</p>

100、;<p><b>　　參考文獻(xiàn)：</b></p><p>　　Drz??la B., Dubiński J.: Lokalizacja ognisk wstrz?sów górniczych. Szko?a Eksploatacji Podziemnej, 1995, Wyd. CPPGSMiE PAN, Kraków.</p>&l

101、t;p>　　Goszcz A.: Elementy mechaniki ska? oraz t?pania w polskich kopalniach w?gla i miedzi. Biblioteka Szko?y Eksploatacji Podziemnej, Kraków 1999.</p><p>　　Konopko W?., Kabiesz J.: Pr?dko?? pos

102、t?pu frontu ?cianowego a zagro?enie t?paniami i metanem. Szko?a Eksploatacji Podziemnej, 1996, Wyd. CPPGSMiE PAN, Kraków.</p><p>　　Konopko W., Kabiesz J., Cygankiewicz J.: Wstrz?sy i t?pania jako i