外文翻譯---深部綜放開采頂煤穩(wěn)定性與支架承載研究

1、<p><b>　　翻譯部分</b></p><p>　　Research on support bearing and top coal stability of fully mechanized caving face in deep mine</p><p>　　ABSTRACT: On the basis of geological and prod

2、uction conditions of 34223 fully mechanized caving face in Quantai coal mine, the distribution of displacement field of top coal deformation is analyzed by means of UDEC3.0 numerical calculating method, which indicates t

3、hat the top coal deformation shows a characteristic of front-to-back dynamic unstable areas. And the impact of support rigidity and rotation angle of main roof on support bearing and on top coal deformation is investigat

4、ed. Last, the f</p><p>　　introduction</p><p>　　Along with the wide application of top coal caving technology in fully mechanized mining face, the powered support for the top coal caving shows a

5、variety of development. And compared with the high-resistance powered support for top coal caving, the light-duty support for top coal caving is in common use due to such advantages as the lower working resistance, lower

6、 cost, light weight, and the convenient operation. With the increase of mining depth, the face condition of “isolated island” formed </p><p>　　SIMULATED GEOLOGICAL AND PRODUCTIVE CONDITIONS</p><p&

7、gt;　　No.3 coal seam is now exploited by 34223 working face of Quantai mine, the thickness of coal seam is 4.5 m, the dip angle is 2 ~ 14°, averaged by 7°. Its Protodyakonov coefficient f is 1.0, being soft in h

8、ardness and simple in structure, with a buried depth of 800 m. The inclined length of the working face is 140 m and the strike length is 708 m. Since the upper and low adjacent coal seams of this working face have alread

9、y been mined out, during the face mining, the working face will become an “</p><p>　　ESTABLISHMENT OF NUMERICAL CALCULATING MODEL</p><p>　　The stability of top coal is influenced by both the sup

10、port rigidity and the movement of main roof, but it can impact on the support bearing as well. In order to analyze the impact of the support rigidity and main roof movement on the stability of top coal and the impact of

11、the stability of top coal on the working resistance of support, the numerical calculation model is established according to the geological condition of 34223 working face (Fig. 1). The model is 150 m in length and 30 m i

12、n hei</p><p>　　The immediate roof and the top coal in the range of the roof-controlled area of the working face are considered as an emphasis to be studied.. In the calculation model, the excavation of the c

13、oal seam starts from the left boundary to make the rotation of main roof form a certain rotation angle. But the rotation angle of the main roof is relevant to the backfilling degree of the goaf, and in the simulation, th

14、e rotation angles of the main roof are determined to be 4.98°, 5.81°, and 8.16°, respect</p><p>　　Table 1 Simulating mechanical parameters of strata</p><p>　　Table 2 Mechanical pa

15、rameters of joint surface in simulating strata</p><p>　　ANALYSIS AND NUMERICAL </p><p>　　CALCULATING RESULT</p><p>　　Deformation characteristic of top coal</p><p>　　If

16、the support rigidity is 80 kN/mm and the rotation angle of the main roof is 5.81°, the displacement vector distribution of the top coal is shown in Figure 2. From Figure 2, it can be seen that the deformation of the

17、 top coal has mainly two areas. The first is the deformation nearby the goaf-side which causes the support to move toward the goaf direction, resulting in the transverse instability of support. And the softer the top coa

18、l is, the larger this area will be. The second is the deformat</p><p>　　Figure 2 Distribution of displacement vector of top coal</p><p>　　Impact of rotation of main roof on top coal stability&l

19、t;/p><p>　　The rotation of the main roof is an important factor influencing on the rock deformation, and its rotation angle is relevant to the backfilling degree of the rock fall in the goaf.</p><p&g

20、t;　　It can be seen that the vertical and horizontal displacements of the top coal increase with the increase of the rotation angle. But if the rotation angle of main roof is small, the displacement is not obvious. The ob

21、vious impact of main roof rotation on the top coal deformation is shown in the vertical displacement of upper top coal and the horizontal displacement of lower top coal</p><p>　　Impact of support rigidity on

22、 stability of top coal</p><p>　　The support rigidity is an important parameter to reflect the supporting performance of the support. Usually, to increase the support rigidity is favorable for controlling the

23、 roof. But as for the top coal caving, the impact degree of the support rigidity on top coal deformation is different under the influence of the mechanical characteristics of the top coal. .</p><p>　　It can

24、be seen that the increase of support rigidity can reduce the vertical displacement of top coal, and finally the vertical displacements of both upper and lower top coals tend to be the same. Meanwhile, the horizontal disp

25、lacement would increase with the increase of the support rigidity. So, if the support rigidity is raised properly and the horizontal component of the support toward the rib direction is kept unchanged, it should be favor

26、able for the roof stability of the end face and for t</p><p>　　From the above analysis, the support bearing is the comprehensive result of the support rigidity, the deformation and breakage degree of the top

27、 coal, and the rotation degree of the main roof. The increase of mining depth will increase the breakage degree of the top coal. The deformation and breakage characteristic of top coal determines that the support bearing

28、 is lowered with the increase of the support rigidity. Therefore, under mining condition of the fully mechanized caving face, if the mai</p><p>　　CONCLUSIONS</p><p>　　1) The deformation of the t

29、op coal in roof-controlled area can be divided into two dynamic instable areas: the front one and the back one. And the size of the dynamic instable area is relevant to the hardness of the top coal. The joint of both are

30、as may result in an instability of rock-support system. And under the condition of the soft coal, the occurrence of the front instable area should be avoided and the back instable area should be also reduced. But, in the

31、 condition of the hard coal, the </p><p>　　2) To increase the rotation angle of main roof will increase both the vertical displacement of upper top coal and the horizontal displacement of lower top coal. And

32、 to increase the support rigidity will decrease the vertical displacement of the top coal but increase the horizontal displacement, with the lower top coal in particular.</p><p>　　3) The support bearing is t

33、he comprehensive result of the support rigidity, the deformation degree of the top coal, and the rotation degree of the main roof. As for fully mechanized caving face, if the main roof can form a relatively stable struct

34、ure of “voussior beam”, the working resistance of support should be properly lowered, and then the light-duty support of top coal caving used is feasible.</p><p>　　REFERENCES</p><p>　　[1] Liu, C

35、.Y., Cao, S.G. & Fang, X.Q. 2003. Relation between rock and support in stope and its monitoring. Xuzhou: Press of China University of Mining & Technology.</p><p>　　[2] Liu, C.Y., Cao, S.G. & Yang

36、, P.J. 1999. Research on bearing characteristics of immediate roof in stope. Journal of Rock Pressure and Ground Control (3 - 4): 35 - 39.</p><p><b>　　中文譯文：</b></p><p>　　深部綜放開采頂煤穩(wěn)定性與

37、支架承載研究</p><p>　　摘要:依據權臺煤礦34223綜放工作面的地質及生產條件，采用UDEC3.0數值計算方法，分析了頂煤變形的位移場分布，得出了頂煤變形呈前后動態(tài)失穩(wěn)區(qū)特征，分析了老頂回轉角、支架剛度對頂煤變形以及支架承載的影響規(guī)律，分析了綜放開采采用輕型支架的可行性。</p><p>　　關鍵詞: 深部，頂煤穩(wěn)定性，支架，承載</p><p>　　隨著

38、綜采放頂煤技術的廣泛應用，放頂煤液壓支架已呈多樣化發(fā)展。與高阻力放頂煤液壓支架相比，輕型放頂煤支架因其工作阻力較低、成本低、重量輕和使用方便等優(yōu)點而在放頂煤開采中得到普遍使用。隨著煤層開采深度的增加，深部開采引起的高應力和開采順序形成的"孤島"工作面條件造成了工作面圍巖應力的疊加，從而給工作面的煤巖控制和安全生產帶來了很大難度和影響。在這種條件下，能否使用輕型放頂煤支架實現厚煤層的安全順利開采，已成為廣泛關注的問題。

39、基于此，本文以權臺煤礦深部高應力綜放開采的地質和生產技術條件為依據，采用UDEC數值計算方法，分析探討了綜放開采老頂運動、頂煤變形與支架承載的關系問題，以期為深部厚煤層綜放開采的支架合理選型等提供參考。</p><p>　　1. 模擬的地質及生產技術條件</p><p>　　權臺煤礦34223工作面開采3煤，煤層厚度4.5m，傾角2～14°，平均7°，煤層普氏系數f為1

40、.0，煤質較軟，煤層結構簡單，煤層埋藏深度800m。工作面傾斜長140m，走向長708m。工作面上部和下部相鄰的煤層均已回采結束，因而該工作面開采時將成為三面臨空的"孤島"工作面。煤層直接頂為厚度3.4m的砂質泥巖，老頂為4.6m厚的砂巖，直接底為厚度1.7m的砂質泥巖。工作面地質構造簡單。</p><p>　　工作面支護采用ZFZ2600－16/24型低位放頂煤液壓支架。支架初撐力1950k

41、N，工作阻力2600kN，支護強度0.45MPa。</p><p>　　2.數值計算模型的建立</p><p>　　頂煤的穩(wěn)定性受到老頂運動程度和支架剛度的影響，同時，又影響到支架的承載。為了分析老頂回轉變形、支架剛度對頂煤穩(wěn)定性的影響，以及頂煤穩(wěn)定性對支架工作阻力的影響程度，依據34223工作面的地質條件，建立圖1所示的數值計算模型。模型長度150m，高度30m。模擬采深800m，模型

42、上邊界施加其上方巖層的自重應力。在工作面控頂區(qū)范圍內的頂煤和直接頂為研究的重點。模型計算時，煤層開挖自左側開采邊界開始，使老頂巖層回轉形成一定的回轉角。老頂的回轉角與采空區(qū)的充填程度有關，模擬中確定老頂回轉角分別為4.98°、5.81°和8.16°。模擬支架剛度分別為40kN/mm、85kN/mm和120kN/mm。計算模型中各巖層的力學參數如表1、表2所示。</p><p>　　表

43、1模擬的煤巖層力學參數</p><p>　　表2 模擬的煤巖層節(jié)理面力學參數</p><p>　　3.數值計算結果及分析</p><p>　　3.1頂煤的變形特征</p><p>　　在支架剛度為80kN/mm、老頂回轉角為5.81°時，頂煤的位移矢量分布如圖2。由圖中可知，頂煤的變形主要有兩個區(qū)域，一是靠采空區(qū)側的頂煤變形，該

44、側頂煤的顯著變形造成支架向采空區(qū)方向運動，形成支架的橫向不穩(wěn)定，頂煤越軟，該區(qū)域越大；二是靠近煤壁的端面頂煤的變形，該處頂煤的冒落將造成端面頂煤變形的加劇和冒落范圍的擴大。因此，依據控頂區(qū)頂煤的變形特征，可將頂煤分為前后動態(tài)失穩(wěn)區(qū)，兩區(qū)域的勾通將造成支架圍巖體系的不穩(wěn)定。</p><p>　　3.2 老頂回轉對頂煤穩(wěn)定性的影響</p><p>　　老頂的回轉是影響煤巖變形的重要因素。其回轉

45、角度與采空區(qū)冒落煤巖的充填程度有關。</p><p>　　隨著老頂回轉角度增大，頂煤的垂直位移和水平位移量增大。但當老頂回轉角較小，頂煤的位移量變化不明顯。老頂回轉對頂煤變形影響顯著的是上位頂煤的垂直位移量和對下位頂煤的水平位移量。</p><p>　　3.3 支架剛度對頂煤穩(wěn)定性的影響</p><p>　　支架剛度是反映支架支護性能的重要參數。一般來說，增大支架剛

46、度，有利于對頂板的控制。但在放頂煤條件下，受頂煤力學特性的影響，支架剛度對頂煤變形的影響程度不同。</p><p>　　增大支架剛度將使頂煤的垂直位移量減小，并最終導致上下位頂煤的垂直位移量趨于一致。而水平位移量則隨支架剛度的增大而增大，尤其是下位頂煤。因此，適當提高支架剛度，并使支架保持向煤壁方向的水平分力，將有利于端面頂板的穩(wěn)定和支架圍巖體系的穩(wěn)定。</p><p>　　綜上分析可得出

47、，支架承載是由老頂的回轉變形程度、頂煤的變形破壞程度和支架剛度綜合作用的結果。采深增加，將增大頂煤的破壞程度。頂煤的變形破壞特征決定了支架承載隨支架剛度增加而降低的特征。因此，在綜放開采條件下，當老頂能形成相對穩(wěn)定的"砌體梁"結構時，適當降低支架工作阻力，采用輕型放頂煤支架是可行的。</p><p><b>　　4.結論</b></p><p>

48、　?。?）控頂區(qū)頂煤的變形可分為前后動態(tài)失穩(wěn)區(qū)，動態(tài)失穩(wěn)區(qū)的大小與頂煤的硬度有關。兩區(qū)域的勾通將造成支架圍巖體系的不穩(wěn)定。在軟煤條件下，應避免產生前失穩(wěn)區(qū)，減小后失穩(wěn)區(qū)。在硬煤條件下，應適當加大后失穩(wěn)區(qū)，以利于頂煤的放落。</p><p>　?。?）老頂回轉角增大將增加上位頂煤的垂直位移量和對下位頂煤的水平位移量。增大支架剛度將減小頂煤的垂直位移量，增大水平位移量，尤其是下位頂煤。</p><

49、p>　?。?）支架承載是由老頂的回轉變形程度、頂煤的變形破壞程度和支架剛度綜合作用的結果。在綜放開采條件下，當老頂能形成相對穩(wěn)定的"砌體梁"結構時，適當降低支架工作阻力，采用輕型放頂煤支架是可行的。</p><p><b>　　參考文獻</b></p><p>　　[1] 劉長友，曹勝根，方新秋. 采場支架圍巖關系及其監(jiān)測控制. 徐州：中國礦