采礦專業(yè)英語外文翻譯---綜放開采巷旁充填沿空留巷技術(shù)研究

1、<p>　　2300單詞，11860英文字符,3290漢字</p><p><b>　　原文：</b></p><p>　　Study on gob-side entry retaining technique with roadside packing in longwall top-coal caving technology</p>&l

2、t;p>　　Abstract：Pointed out some technical difficulties of gob-side entry retaining with roadside packing in longwall top-coal caving technology (LTCT), and analyzed the function mechanism of roadside filling body. The

3、ory analysis shows the mechanical properties of highwater material fit for the feature of deformation of gob-side entry retaining in LTCT, and gob-side entry retaining in LTCT face is one of effective ways to increase th

4、e recovery ratio of mining district.</p><p>　　Key words ：gob-side entry retaining, roadside packing, longwall top-coal caving, support resistance</p><p>　　Introduction</p><p>　　Now

5、the longwall top-coal caving technology (LTCT) in China has shown its advantages such as advanced technique, small investment, low cost, high efficiency in production and good safety and the like.</p><p>　　T

6、he LTCT will be adopted widely in view of the abundant reserves of thick seam in China. However,the mining district recovery ratio in LTCT is still very low because of some restricts from LTCT process. The statistics sho

7、ws that the coal loss caused by coal pillar is about 9.5% of that of the whole district and that a great number of gate-roads by LTCT are protected by wide chain pillars, resulting a plenty of coal lost and limiting seri

8、ously the further increase of the coal recovery ratio in LT</p><p>　　1 Several technical problems</p><p>　　(1) With the great height of coal seam mined out once, the scope of ground behaviors in

9、crease accordingly. Because of the increase of the mining height and the superposition of the abutment pressure caused by mining from face and neighbor mined areas, the surrounding rock stress of the roadway increases, a

10、nd the maximum value of it is 5 to 6 times of in-situ rocks. In LTCT, the distance influenced by the front abutment pressure of working face gets longer, moreover, the mining roadways are fully</p><p>　　(2)

11、What is on the top of the gob-side entry is coal seam. Being low strength, the top-coal is crushed easily to fall into goaf, which often leads to a unsupported roof appearing above the roadway. So, it is anessential and

12、difficult issue to keep the stability of the top-coal of roadway.</p><p>　　(3) Long-term research on the ground pressure behavior rule of gob-side entry in LTCT indicates:top-coal, immediate roof and main ro

13、of all present as overhanging beams, the bearing point of which is the coal wall. With approaching working face, the overhanging beam turns rapidly and its subsidence is in direct proportion to the height mined out at on

14、e time.The coal wall in LTCT not only bears high abutment pressure but also as the bearing point of the mined area. Thereby, a great bulging toward </p><p>　　(4) Because of the large strength of mining, the

15、big airflow quantity required and the large room that occupied by the conveyer in working face, the end transloader and the belt conveyer, a large section area of roadway must be required to meet the need for equip-ment

16、transportation, ventilation and walking,which makes it very difficult to retain and maintainthe roadway.</p><p>　　(5) Both ends of face in LTCT are supported by end supports. When the working face is pushed

17、and end supports are removed forward, the top-coal will fall immediately after mining because of its low strength, which makes it difficult to retain in advance the space for gob-side supporting zone to some extent.</

18、p><p>　　(6) The height of the roof controlling by roadside support is in direct proportion to the thickness of coal mined out. For ensuring to have enough support strength to cut the roof of big height required

19、 in LTCT,the roadside supporting zone is required to have larger width. It increases the difficulty to establish the supporting zone beside roadway.</p><p>　　(7) Air leakage from gob-side entry along goaf si

20、de provides continual oxygen for spontaneous burn of the remaining coal in gob. So, ensuring the quality of roadside filling body is very important.</p><p>　　2 Technical analysis</p><p>　　(1) Th

21、e surrounding rock control of gob-side entry retaining in LTCT mainly is how to control the interior rock of roadway before or after entry retaining and how to fill after entry retaining. The quality of surrounding rock

22、control of roadway before entry retaining is directly relate to whether the gob-side entry retaining can obtain success or not. The excessive deformation of roadway before filling should be controlled,which must not only

23、 depends on the passive bearing load capacity of the s</p><p>　　(2) To make the top-coal above the roadway and the supporting zone beside roadway not fall and keep a good integrality, polyure-thane should be

24、 injected into the coal body of both ends of the face to reinforce the coal body.</p><p>　　(3) To keep the integrality of top-coal in the space to be filled and to improve the load distribution of support be

25、side roadway, the following measures can be taken: decreasing a set of support at the end-face along the side of entry retaining, matting the steel gauze in advance during mining, adding a long inclined junction timberin

26、g and monomer hydraulic props along the interior side of filling body, keeping three rows monomer hydraulic props at the rear of support till the next filling endin</p><p>　　(4) Because of the high advancing

27、 rate in LTCT,a fully mechanized filling system and a good filling material are required in order to establish the supporting zone beside roadway timely following with the working face. Especially, the filling body must

28、have a good capacity of bearing load and deformation. A lot of mining practices for moderately thick seam show that high-water material and its filling system is able to meet the need above mentioned.</p><p>

29、;　　3 Function mechanism of high-water fasthardening material as roadside fillingbody</p><p>　　As a kind of roadside filling body, the function mechanism of high-water fast hardening material are stated as fo

30、llows:</p><p>　　(1) Roadside filling body is required to have a certain support resistance to support the unload top-coal and immediate roof within a given range at the rear of working face. If the support r

31、esistance is very low or the supporting isn’t in time, the top-coal and immediate roof will crack along the foot wall of roadway, resulting a badly damage and a large prophase deformation in roadway. So the roadside fill

32、ing body should be characterized by a high solidify-Cation rate and a high early strength</p><p>　　(2) With the working face is pushed forward, the main roof will break and destabilize in sequence, at this t

33、ime, the filling body’s resistance should reach the resistance of roof cutting-off. When the bending moment in main roof strata reaches to the limited value at the edge of roadside filling body, the main roof will be cut

34、 off orderly. In LTCT, the height of roof cutting is large, so the filling body should have a large resistance of roof cutting.</p><p>　　(3) When the rock falls into goaf, its volume increases.When the goaf

35、is full of broken rock, the upperstrata is bolstered by coal body, support of roadway and roadside filling body together, till reach to balance. Under this condition, the deformation of roadway will tend to moderation an

36、d get a balance gradually, the roadside filling body should be able to keep the balance of broken strata above roadway at this time, thus, the roof subsidence of roadway can be controlled within the range of de</p>

37、<p>　　(4) Considering medium’s stiffness matching,one side of roadway is the elastic-plastic coal body,and the other is filling body. The coal body can provide with certain yieldable capacity, if the filling body

38、has a little yieldable capacity or is a rigid basically, it will cause the roof to subside unevenly. Lab research and production practice show that high-water material has a good yieldable property.</p><p>　

39、　4 Support resistance of the roadside filling body</p><p>　　(1)Initial support resistance required</p><p>　　It is the top-coal and immediate roof that is supported by filling body at the initial

40、 stage (1 day). The interaction mechanics model is shown as the Fig.1.The analysis of the load on coal-rock block ‘ABCD’ is stated as follows. </p><p>　　For safety, we can consider the coal-rock block ‘ABCD’

41、 have no mechanics relation to its surrounding rocks. From =0,then</p><p><b>　　(1)</b></p><p>　　Fig.1 Mechanical behavior of rockstrata around roadretained for next sublevel about mi

42、ning with fully mechanizedsublevel caving</p><p>　　1—roadside filling body；2—gob-side entry retaining roadway</p><p>　　From formula (1), the following equation can be obtained.</p><p&

43、gt;<b>　　(2)</b></p><p>　　Considering the periodic weighting and introducing the increa-sing coefficient of periodic weighting Kt, the formula (2) can be expressed by</p><p><b>

44、　　(3)</b></p><p>　　Where, Pc is the support resistance of the one dayaged filling body, N/m; Ph is the average strength of support to coal-rock block ‘ABCD’ and immediate roof by support of roadway, N/

45、m2; a is the width of roadway, m; b is the width of filling body, m; u is the filling length per day, m; l is the distance from filling body to working face, m; hm and hz are the height of top-coal and immediate roof res

46、pectively, m; and are the specific gravity of top-coal and immediate roof respectively,N/m3.</p><p>　　(2)Support resistance of roof cutting</p><p>　　With the working face advancing, the roof-c

47、ontrolling field increases, inducing main roof to break and destabilize in sequence. A reasonable cutting-off height should ensure gob to be filled with break rocks and make overlying strata obtain a stability with the a

48、butment by refuse, coal body, support of roadway and filling body together. Because the cutting-off height depends on the cutting-off resistance, the proper support resistance of filling body should make the roadway tren

49、d to stability ea</p><p><b>　　(4)</b></p><p>　　Where, K is the coefficient of main roof cutting-off,generally K=3.</p><p>　　5 Conclusions</p><p>　　(1) It is

50、 fully feasible to realize a gob-side entry retaining for next sector in LTCT face by reforming the traditional support pattern such as bolting (cable anchor), reinforcing the coal body at both ends of face,adopting full

51、y mechanized filling system and good filling material, and so on.</p><p>　　(2) Theory analysis shows the mechanical properties of high-water material is fit for the feature of deformation of gob-side entry r

52、etaining in LTCT. It’s an ideal material for roadside filling.</p><p>　　(3) For providing high initial resistance for gob-side entry retaining in LTCT, a high-strength filling body is required. Generally, th

53、e width of filling body in LTCT face for thinner and moderately thick seam is required to be greater.</p><p>　　(4) Gob-side entry retaining in LTCT face is one of effective ways to increase the recovery rati

54、o of mining district, but a lot of problems urgently required further study and solution, It is suggested that industrial test should be conducted to obtain more experience for its application under proper condition abou

55、t this technology.</p><p><b>　　譯文：</b></p><p>　　綜放開采巷旁充填沿空留巷技術(shù)研究</p><p>　　摘要：指出了在綜放開采中應用巷旁充填沿空留巷技術(shù)的幾個技術(shù)難題，分析了巷旁充填體的作用機理。理論分析表明高水材料的力學性能適應于綜放開采沿空留巷的變形特征，在綜放面實行沿空留巷也是提高采區(qū)回

56、采率的有效途徑之一。</p><p>　　關鍵詞：沿空留巷，巷旁充填，綜放開采，支護阻力</p><p><b>　　前言</b></p><p>　　目前我國綜放開采技術(shù)已經(jīng)顯示了它的優(yōu)越性，如技術(shù)先進、投資少、成本低、效率高、安全性好等?？紤]到我國厚煤層儲量豐富，綜放開采技術(shù)將得到廣泛應用。但是由于綜放工藝的一些限制因素，綜放開采的工作面采

57、出率仍然很低。據(jù)統(tǒng)計，在綜放采區(qū)的煤炭損失中，工作面區(qū)段煤柱損失約占9.5%，許多綜放面順槽巷道使用寬煤柱護巷，導致了煤炭的大量損失，嚴重制約了綜放面煤炭回采率的進一步提高。結(jié)合綜放面的特點，進行了大量的現(xiàn)場試驗和理論研究，對于提高采區(qū)采出率、減少巷道掘進率和緩解采掘接替矛盾具有重要意義，同時可進一步推動綜放開采的可持續(xù)發(fā)展。巷旁充填沿空留巷是實現(xiàn)綜放面無煤柱開采的途徑之一。</p><p><b>　

58、　1 幾個技術(shù)問題</b></p><p>　?。?）綜放開采一次采出煤層厚度大，上覆巖層的活動范圍相應增加。由于采高的增加和綜放面及已采面采動所引起的支承壓力的疊加作用，巷道圍巖壓力增大，最大可達原巖應力的5～6倍。綜放開采時，工作面超前支承壓力影響距離增大，且回采巷道完全沿煤層掘進，所以礦壓顯現(xiàn)劇烈，而沿空巷道的頂?shù)装逡平颗c開采高度成正比。當厚煤層一次采出時，巷道的頂?shù)装逡平渴欠謱娱_采的數(shù)倍，

59、而且在綜放工作面的前方，巷道斷面的收縮率很大。若不采取合理的支護方式和超前加強支護，沿空巷道的變形將會快速增加甚至超出控制，使所留巷道在下區(qū)段不能正常使用。</p><p>　?。?）沿空巷道的上部為煤層。頂煤強度低，易被壓碎落入采空區(qū)，造成巷道上方空頂，所以保證巷道頂煤的穩(wěn)定性是十分重要而又困難的。</p><p>　?。?）對綜放面沿空巷道礦壓顯現(xiàn)規(guī)律的長期研究表明：頂煤、直接頂和老頂

60、都呈現(xiàn)出以煤壁為支承點的懸臂梁狀態(tài)。隨著臨近工作面，懸臂梁急劇轉(zhuǎn)動，它的沉降量與一次開采厚度成正比。綜放面煤壁不僅承受高的支承壓力，而且作為已采區(qū)的支承點，因此煤壁會向巷道空間擠出，產(chǎn)生嚴重脹形。這不僅導致煤壁的強烈位移，而且會增加懸臂梁的回轉(zhuǎn)角，引起巷道頂煤的急劇沉降。因此，控制煤壁的強烈位移是有效控制沿空巷道變形的關鍵。</p><p>　?。?）由于回采強度大，所需風量大，工作面運輸機、端頭轉(zhuǎn)載機和皮帶輸送

61、機空間體積大，因此需要增大順槽斷面以滿足設備運輸、通風和行人的需要，使得巷道難以保留和維護。</p><p>　?。?）綜放工作面端頭由端頭支架支護。隨工作面推進和端頭支架的前移，頂煤由于強度低采后隨之冒落，給預留巷旁支護帶空間帶來一定困難。</p><p>　?。?）巷旁支護控頂高度與采出煤層的厚度成正比。由于綜放面需切落頂板高度較大，為保證巷旁支護帶有足夠的支護強度切落頂板，巷旁支護帶

62、需要有較大寬度，增加了構(gòu)筑巷旁支護帶的難度。</p><p>　　（7）沿空巷道采空側(cè)的漏風為采空區(qū)遺煤的自燃提供了持續(xù)的供氧條件。因此，保證巷旁充填體的質(zhì)量是很重要的。</p><p><b>　　2 技術(shù)分析</b></p><p>　?。?）巷旁充填前要控制巷道的過度變形，而控制其過度變形不僅要依靠支架的被動承載能力，而且應充分利用巷道圍

63、巖的自承能力。錨桿（索）網(wǎng)支護可把被動支護變?yōu)橹鲃又ёo，改善圍巖應力狀態(tài)，發(fā)揮圍巖的自承能力。綜放面沿空留巷的圍巖控制主要是留巷前后如何控制巷道內(nèi)部圍巖及留巷后如何充填。留巷前巷道圍巖控制的質(zhì)量直接關系到沿空留巷能否取得成功。另外，對圍巖施加足夠的橫向力可增加破碎煤體間的摩擦力，保持煤體處于徑向連續(xù)狀態(tài)，是圍巖保持較高的三向應力狀態(tài)。同時可防止頂板早期離層，也有利于增加巷道的凈斷面。為避免巷道在巷旁支護前后因工作面超前和滯后支承壓力造成

64、較大變形，在工作面前后方一定區(qū)域內(nèi)必須進行加強支護。</p><p>　?。?）為保證巷道及巷旁充填體上方的頂煤不冒落并保持完整性，需對工作面上下端頭的煤體注聚氨酯以加固煤體。</p><p>　?。?）為保證待充填空間頂煤的完整性和改善巷旁支護的受力狀況，應采取以下措施：在留巷側(cè)工作面端頭待充填空間處少安裝1組支架，回采過程中預鋪金屬網(wǎng)，在充填體內(nèi)側(cè)打加長傾斜抬棚和單體液壓支柱，支架后方

65、始終保持3排單體液壓支柱,直至下一步充填工作結(jié)束后回撤，工作面端頭采用長Π形鋼梁交錯前進支護,在Π形鋼梁上鋪設菱形金屬網(wǎng)。</p><p>　?。?）由于綜放面推進速度快，為保證巷旁支護帶能緊隨工作面及時構(gòu)筑,需采用綜合機械化巷旁充填系統(tǒng)和良好的充填材料,充填體尤其要有好的承載特性和變形性能。中厚煤層沿空留巷大量工程實踐表明,高水材料及其充填系統(tǒng)可滿足上述要求。</p><p>　　3 高

66、水速凝充填材料巷旁充填體作用機理</p><p>　　作為一種巷旁充填體，高水速凝材料巷旁充填體作用機理如下:</p><p>　?。?）在工作面后方某一范圍內(nèi),巷道頂煤與直接頂已經(jīng)卸載,此時巷旁充填體需有一定的支護阻力。如果支護阻力低或支護不及時，頂煤與直接頂就會沿巷道煤幫斷裂，造成巷道嚴重破壞或前期變形過大。因此，巷旁充填體應具有凝固速度快、早期強度高的特點。另外，必須緊隨工作面構(gòu)筑充

67、填體，及時支護頂煤及直接頂，確保頂煤和直接頂不破碎，避免其與老頂離層，并切斷巷道靠采空區(qū)側(cè)的頂煤與直接頂，以減小巷旁充填體所承受的壓力。由于巷旁充填高水材料的早強性高，可有效控制頂部煤巖層的破裂位置，達到預期的切頂目的，有效地保護巷道內(nèi)頂板（煤）的完整性和自承能力，進而減小頂板的早期下沉量和巷道斷面收縮率。</p><p>　?。?）隨著工作面推進，老頂會依次破斷、失穩(wěn)，此時，充填體的支護阻力應達到切頂阻力。當老

68、頂巖層中的彎矩在巷旁充填體的邊緣達到極限值時，老頂將被依次切斷。綜放開采時，切頂高度很大，所以充填體應當有較大的切頂阻力。</p><p>　?。?）矸石落入采空區(qū)時體積增大，當采空區(qū)充滿破碎巖石時，更上位的巖層在煤體、巷道支護和巷旁充填體的共同支撐作用下達到平衡。在這種條件下，巷道圍巖變形趨于緩和并逐漸穩(wěn)定，此時巷旁充填體應能維持巷道上方破斷巖層的平衡，將巷道頂板下沉量控制在設計要求的范圍內(nèi)。</p>

69、;<p>　?。?）從介質(zhì)的剛度匹配來說，巷道一側(cè)是彈塑性截介質(zhì)的煤體，另一側(cè)是巷旁充填體。煤體具有一定的可壓縮量，而巷旁充填體的可壓縮量很小或基本上是剛性的，會造成頂板下沉不均勻。實驗室研究和生產(chǎn)實踐表明，高水材料有良好的可縮性。</p><p>　　圖1 巷旁充填體與圍巖相互作用的力學模型</p><p>　　1—巷旁充填體；2—沿空巷道</p><p

70、>　　4 巷旁充填體支護阻力</p><p>　　(1)巷旁充填體初期所需支護阻力</p><p>　　巷旁充填體構(gòu)筑初期（1d）支護頂煤與直接頂。相互作用的力學模型如圖1所示。下面對圖中所示的ABCD煤巖塊進行受力分析。</p><p>　　為安全起見，設ABCD煤巖塊與圍巖無力學聯(lián)系,則由∑Fy=0得</p><p><b&g

71、t;　　(1)</b></p><p><b>　　由式（1）得下式：</b></p><p><b>　　(2)</b></p><p>　　考慮工作面周期來壓，引入周期來壓增壓系數(shù)，式（2）可表示為：</p><p><b>　　(3)</b></p>

72、;<p>　　式中，為巷旁充填體1d后的支護阻力，N/m;為巷內(nèi)支護對ABCD塊頂煤與直接頂?shù)钠骄ёo強度，N/m2 ;為巷道寬度，m；為巷旁充填體寬度，m；為每日充填長度，m；為充填體距工作面的距離，m；和分別為頂煤和直接頂厚度，m；和分別為頂煤和直接頂?shù)娜葜?，N/m3。</p><p><b>　?。?）切頂支護阻力</b></p><p>　　隨著

73、工作面推進，控頂范圍增加，引起老頂依次破斷、失穩(wěn)。合理的切頂高度應能使采空區(qū)充滿破碎矸石，使上位巖層在矸石、煤體、巷道支護和充填體的共同支撐作用下處于平衡狀態(tài)。由于切頂高度取決于切頂阻力，充填體必須具有一定得切頂阻力以使巷道及早趨于穩(wěn)定。根據(jù)非放頂煤實踐經(jīng)驗與試驗結(jié)果，并經(jīng)統(tǒng)計分析表明，切頂阻力與初期支護阻力的關系可用下式表示：</p><p><b>　　(4)</b></p>

74、<p>　　式中，為老頂切頂系數(shù)，一般取=3。</p><p><b>　　5 結(jié)論</b></p><p>　?。?）通過改革傳統(tǒng)的支護方式如錨桿（索）支護、加固工作面兩端的煤體、采用機械化程度高的充填系統(tǒng)和良好的充填材料等，在綜放面為下區(qū)段沿空留巷是完全可行的。</p><p>　　（2）理論分析表明，高水材料的力學性能能適用

75、于綜放面沿空留巷圍巖變形特點，是一種理想的巷旁充填材料。</p><p>　?。?）綜放面沿空留巷巷旁充填體所需初期支護阻力較大，要求巷旁充填體強度較高。一般情況下，綜放開采時，較薄和中厚煤層工作面沿空留巷巷旁充填體所需寬度較大。</p><p>　?。?）綜放面沿空留巷是提高采區(qū)回收率的有效途徑之一，但仍有許多問題亟待進一步研究和加以解決。建議在適宜條件下對綜放開采巷旁充填沿空留巷技術(shù)進