外文翻譯--關(guān)于傾角煤層挖掘巷道的錨桿支護(hù)的研究

1、<p><b>　　中文3890字</b></p><p><b>　　英文原文</b></p><p>　　STUDY ON GATEWAY BOLTING EXCAVATED IN</p><p>　　INCLINED COAL SEAM</p><p>　　(Northeastern

2、 University ,Shenyang 110006)</p><p>　　(Chengdu University of Technology.Chengdu 610059)</p><p>　　Abstract： </p><p>　　A typical gateway is analyzed using fully-deformable discrete e

3、lement method. The fractured zone around the gateway is measured in field. Based on the measurement results and theoretical analysis, a comprehensive support scheme adopting bolt and steel belt is proposed. Discrete elem

4、ent method is used to asses the bolting scheme, and displacement monitoring in field is also carried out. Having been put into practice, it is proved that the scheme is both successful and rational. According to theor<

5、;/p><p>　　Keywords: inclined seam; gateway; strata behavior; bolting; discrete element method</p><p>　　Introduction</p><p>　　Inclined coal seam is generally regarded as seam with a di

6、p single 25~,which occupies a considerable proportion in both production and reserves in China. Problems related to strata control are, however, seldom studied, and researches on in-seam gateway are even .</p><

7、;p>　　The maintenance expense of gateway in inclined seam is generally 30% higher than that in nearly flat and gently inclined seam. The reason why there exists a such phenomenon is complicated itself, another possible

8、 reason is the lack of the inherent strata behavior law.</p><p>　　At present, problems related to in-seam gateway maintenance are highly emphasized and many studies on strata behavior and support of gateway

9、are carried . Such researches play a positive role in gateway maintenance.</p><p>　　However most of the researches are carried out in flat or gently inclined seams. Due to their locating in remarkably anisot

10、ropic media and environment, gateways in inclined seams are often subjected to unfavorable loads and deform unevenly, strata move more intensively than that in gently inclined seam, and the broken region is also large, w

11、hich makes gateway support even more difficult. </p><p>　　In view of the above-mentioned facts, we use fully deformable discrete element method in simulating strata behavior of gateway in inclined seam, and

12、the loosed zone around the gateway is also monitored in field. Based on the results, a bolting scheme is proposed. After putting into practice, the scheme is proved to be effective and rational.</p><p>　　Def

13、orm and fail features of gateway without any support </p><p>　　1.1 Geologic conditions</p><p>　　The study object is the No.36 seam in Baoshan Coal Mine , the dip angle of the seam is 35°an

14、d thickness is 1.0m, the geologic conditions are rather simple. The average buried depth is 440m. The immediate roof is 2 meters thick of fine sandstone and shale, the overall strength is low. Above the immediate roof is

15、 comparatively hard main roof. The floor is fine sandstone. The gateway width is 2.2m and the gateway is excavated in irregular shape in order to keep the roof intact. The sidewall coal is</p><p>　　1.2 Simu

16、lation of gateway deformation and failure with discrete element method</p><p>　　The joint statistical results show that the surrounding rocks of the gateway are cut by two orthogonal joints, one group is the

17、 bedding plane of the coal measures, another group is normal to the bedding plane, mainly developed in the immediate roof. Because of the low strength of immediate roof, there often exist long joints that cross through t

18、he immediate roof. Such long joints play a dominant part in roof falling. According to the spatial distribution of joints, a discrete element model is bu</p><p>　　After the gateway is excavated, under the ac

19、tion of initial stresses, the upper sidewall coal firstly breaks, then the surface of the lower sidewall coal begins to yield. The abutments of the roof at the two sidewall transfer to deep solid coal in consequence .The

20、 immediate roof at the surface of the gateway begins to bend, bedding separate, fail and fall(see fig 2),as a result, large area of the roof falls until up to the main roof Some broken blocks may collapse when a small di

21、sturbance occurs</p><p>　　The results indicate that two sidewall coals fail differently the upper coal breaks more intensively than the lower sidewall coal.</p><p>　　According to the above-menti

22、oned analysis, it can be seen that in middle to lowly hard thin inclined seam, the stability of the two sidewall coals is very important to the overall stability of the gateway. If the sidewall fails, then the abutments

23、of the roof will transfer to deep solid coal, as a result the free span of the roof increases, which aggravates the unstable condition of the whole gateway .Such failure of surrounding rocks is even serious when it is su

24、bjected to mining influence .It </p><p>　　Measurement of loosed zone around gateway</p><p>　　Based on loosed zone theory of excavation, a loosed zone is generally formed around the excavation i

25、f which the stress is lower than the initial stress. Owing to irregular shape of gateway in inclined seam and anisotropic media, the loosed zone around gateway is certainly in irregular shape. We use an ultrasonic joint

26、detector(Type SC-II by Fushun institute of Coal Science and Technology) to measure the loosed zone of the gateway. The test results are shown in Fig.3. The gateway was supported by</p><p>　　The gateway can b

27、e stable without mining influence. But as long as being subjected to mining activity, the gateway will collapse wit sidewall failing and roof falling. In extreme case, the maximum caving height can reach as high as 4.0m.

28、</p><p>　　As a result , the gateway in the seam is very difficult to be maintained and the maintenance cost is thus rather high. The test results are coincided with the numerical calculation. So it is, there

29、fore, necessary to reinforce the gateway including the sidewall comprehensively.</p><p>　　Inclined combined beam model for roofbolts</p><p>　　In inclined seam, roofbolts combine roof together wh

30、en bolt length is shorter than the soft and loose roof. Of course, if the bolt can be bolted at a competent stratum, then the bolting mechanism will become hanging over. A typical inclined combined beam model is illustra

31、ted in Fif.4. The beam is composed by several (total numbers of layers are k) different kinds of strata, with length L and thickness . It is assumed that (1) each layer of the beam is homogeneous, continuous and isotropi

32、c; (2) t</p><p>　　According to strength criteria of the beam, the minimum thickness can be derived and then the total length of a bolt can be easily determined as follows:</p><p><b>　　(1)

33、</b></p><p>　　Where , is the length of bolted end ; is the length of outer part.</p><p>　　Bolt spacing a can be derived by the criteria that no slip occurs along bedding planes. Besides

34、the above-mentioned conditions, the safety of the combined beam must be checked to prevent it from longitudinal instability.</p><p>　　When all the conditions are satisfied, roof bolt parameters can ready be

35、determined. As for sidewall bolts, their length and spacing can be derived by soil bracing theory in soil mechanics.</p><p>　　It should be noticed when roof is composed of weak and loose strata, some bracin

36、g measures must be taken to protect the integrity of the fragile roof.</p><p>　　Bolting of the gateway and its assessment </p><p>　　4.1 Support assessment by discrete element method </p>

37、<p>　　We consider two case in order to compare , first</p><p>　　case: only the roof is bolted; second case: both roof and sidewall are bolted.</p><p>　　Having been bolted in the first case

38、, the roof has a obvious higher stiffness and strength, in the initial stage, only slight deflection occurs. However, with the sidewall coal failing and caving, the free span of the roof increases, the roof gradually ent

39、ers unstable stage, subsiding and bedding separating as shown in Fig.5. Compared with the unsupported gateway, the gateway with roof bolted can keep stability for much longer time even it destabilizes finally.</p>

40、<p>　　In the second case, the sidewall coal deformation and failure are strictly controlled by the sidewall bolts, the sidewalls are stable. Roof deflects only a small amount. Displacement can be hardly seen in the

41、 block diagram(Fig.6).</p><p>　　The overall surrounding strata are in stable conditions. Even influenced by mining activity the gateway only fails locally, the roof is, however rather stable. It is, thus imp

42、ortant to adopt a comprehensive bolt support pattern including the sidewalls.</p><p>　　4.2 Bolting scheme and its implementation </p><p>　　Based on the inclined combined beam theory, gateway lo

43、osed zone measurement and discrete element analysis, four bolts 1.6m long are installed in the roof. At the outer end of each bolt, a testing device is installed( of National Bureau of China) to ensure that at least 20kN

44、 pretension is exerted. Bolt spacing is 0.75m, array pitch is 1.0m. Due to rather developed joints, steel bends are used together with roof bolt to ensure support effectiveness and prevent local roof caving. The steel pl

45、ate is</p><p>　　The coal sidewall is reinforced by timber bolt with spacing 1.0m, timer bolt for upper sidewall is 2.0m long and 1.0m for the lower sidewall. The timber bolt is installed with no less 7.5kN p

46、retension.</p><p>　　In the influence zone of front abutment pressure, strengthened supports are added. Metal frictional prop with timber cap is set as temporary reinforcement. The reinforcement distance is 2

47、5m ahead of the working face. The reinforced props are arranged in the center line of the gateway.</p><p>　　More attentions should be paid to gateway excavation procedure. The roof bolts should be installed

48、as soon as possible after the roof is exposed, then the sidewall bolt. The maximum delayed time should be less than 6 hours, which can make the roof deform exceedingly and integrity worsening. After each construction cyc

49、le, the bolts near the driving face should be refastened to assure their anchorage force.</p><p>　　4.3 Measurement of gateway closure</p><p>　　In order to assess the effectiveness of the suppor

50、t scheme, the gateway closure is monitored during its driving and working face retreating.</p><p>　　The closure of roof vs floor, sidewalls and roof subsiding velocity are shown in Fig.7. </p><p&g

51、t;　　It can be seen that when the working face is far away from the monitoring area, the deformation of the surrounding rocks is very small, indicating that the gateway is not influenced by face dynamic pressure , the sup

52、port system can easily bear the static load of gateway itself. With the working face advancing, the gateway begin to sense the dynamic action of the working face.</p><p>　　When the distance between the face

53、and monitoring area is around 20 meters, the deforming velocity of surrounding is increasing obviously and the strata is moving remarkably, such response of the gateway is the dynamic action of the working face. The test

54、ing results show that the reinforced distance should be more than 20 meters. However , from the overall status of the surrounding rock, the gateway is in stable conditions and can satisfy the demand of coal transportatio

55、n, air intake and other e</p><p>　　In spite of the fact that there are 2~3 groups of joints distinctively shown if the roof, the roof is, however stable under the combined action of roof bolts and steel bens

56、. The upper sidewall coal fails and falls in some places, but the depth is limited within 0.6m.</p><p>　　Based on the facts in field, in brief, the support scheme is rational and effective. Good economic and

57、 rechnical benefit were obtained.</p><p>　　Conclusion </p><p>　　The failure pattern of gateway in inclined seam is remarkably anisotropic. The failure zone is not only related to the mechanical

58、properties of strata, but also closely to the stability of sidewall coal body. The sidewall coal failure causes the abutment points to transfer into deep solid coal, increase the free span of the roof and therefore worse

59、n the roof integrity. It is, thus a key task to keep the gateway sidewall sound in gateway maintenance.</p><p>　　By gateway loosed zone testing, combined with the inclined combined beam model, bolt parameter

60、s can be readily determined. Discrete element method can be adopted to verify the rationality and make some amendment . As for the roof with multiple soft and loose layers, ensuring bolt pretension and installing roof bo

61、lts as early as possible are the keys to make the roof stable. Meanwhile, to keep roof integrity with steel bends (sometimes metal net is needed) is another important measure. It is prov</p><p>　　References&

62、lt;/p><p>　　陶連金. 大傾角煤層開采礦山壓力顯現(xiàn)及其控制[學(xué)位論文]. 沈陽(yáng)：東北大學(xué). 1996。70~79</p><p>　　候朝烔，郭宏亮.我國(guó)煤巷錨桿動(dòng)手術(shù)的發(fā)展方向：煤炭學(xué)報(bào)，1996，21（2）：113~118</p><p>　　陳炎光主編. 中國(guó)煤礦巷道圍巖控制.徐州：中國(guó)礦業(yè)大學(xué)出版社，1995（3~4）：67~70</p>

63、<p>　　陶連金. 寶山煤礦巷道圍巖松動(dòng)范圍測(cè)試.建井技術(shù),1993(3~4):67~70</p><p>　　5劉明遠(yuǎn)，陶連金，李芳成等 錨桿預(yù)緊力標(biāo)示圈. 1993，國(guó)家專利號(hào)：93208997.6</p><p>　　6 張倬元，王士天 工程動(dòng)力地質(zhì)學(xué). 北京: 中國(guó)工業(yè)出版社, 1964</p><p>　　7 張倬元. 工程地質(zhì)分析原理.

64、北京：地質(zhì)出版社, 1994.3</p><p>　　8 張卓元. 工程地質(zhì)勘探. 北京：地質(zhì)出版社, 1981</p><p><b>　　中文譯文</b></p><p>　　關(guān)于傾角煤層挖掘巷道的錨桿支護(hù)的研究</p><p><b>　　摘要:</b></p><p&g

65、t;　　一種典型的巷道是使用完全可變形的離散元素法。巷道周圍的斷裂區(qū)域是有規(guī)則的。在測(cè)量結(jié)果和理論分析的基礎(chǔ)上，一種全新的使用錨桿和鐵板的支護(hù)方案被提出。離散元素法被用于評(píng)估錨桿支護(hù)方案，并且取代了在現(xiàn)場(chǎng)上經(jīng)常采用的監(jiān)測(cè)手段。自從投入到實(shí)際應(yīng)用以來，這種方案被證實(shí)是成功的和正確的。對(duì)于理論分析和現(xiàn)場(chǎng)的監(jiān)測(cè)，一些在巷道螺栓連接的實(shí)踐中必須被注意的關(guān)鍵點(diǎn)最好還是總結(jié)一下。</p><p>　　關(guān)鍵詞 : 傾斜地層;

66、巷道; 地層運(yùn)動(dòng); 錨桿支護(hù); 離散元素法</p><p><b>　　概述</b></p><p>　　傾角煤層一般是指煤層有一個(gè)25到45的下沉角度，這種煤層在中國(guó)的產(chǎn)量和儲(chǔ)存量中占有相當(dāng)大的比例。涉及到地層控制的問題，很少被研究，并且研究地層巷道的學(xué)者就更少了。</p><p>　　維護(hù)傾斜煤層巷道的費(fèi)用一般來說比近似平直和逐漸傾斜的煤層

67、巷道的費(fèi)用要高百分之三十。導(dǎo)致出現(xiàn)這種現(xiàn)象的原因一是自身的復(fù)雜情況，另一個(gè)是基本的地層運(yùn)動(dòng)理論。</p><p>　　目前，關(guān)于煤層巷道的維護(hù)問題已經(jīng)引起關(guān)注，并且許多關(guān)于地層運(yùn)動(dòng)和巷道的支撐的研究已經(jīng)展開了。這些研究在巷道的維護(hù)過程中，起到了積極的作用。</p><p>　　然而，大多數(shù)研究是圍繞平直或者是逐漸傾斜的煤層展開的。由于他們是定位在非常特殊的各有異性的媒介和環(huán)境中的，而在傾斜

68、煤層的巷道通常受到不利的載荷并且不均衡的產(chǎn)生變形，地層運(yùn)動(dòng)比逐漸傾斜的煤層要強(qiáng)烈，另外遭到破壞的區(qū)域也是很大的，這就造成了巷道的支撐更加困難。</p><p>　　從以上提到的情況來看，我們?cè)诜抡鎯A斜煤層巷道的地層運(yùn)動(dòng)中使用了完全可變形離散元素法，并且在巷道的承載小的區(qū)域也被監(jiān)控起來。基于這些監(jiān)控結(jié)果，一種螺栓連接的方法被提出。等到付諸實(shí)踐以后，這種方法被證明是有效的并且是合理的。</p><

69、p>　　1 沒有任何支撐的巷道的變形和實(shí)效特征</p><p><b>　　1.1 地質(zhì)條件</b></p><p>　　研究對(duì)象是寶山煤礦的第36號(hào)煤層，煤層的向下傾角是35度，煤層厚度是1米 ，地質(zhì)條件是相當(dāng)簡(jiǎn)單的。平均的埋藏深度是440米。巷道上緊接著的頂是2米厚的沙巖和頁(yè)巖，施加全部的載荷是低的。再一層是比較硬的重要的頂。這一層是沙巖。巷道的寬度是2.2

70、米并且為了保持頂不被改變，巷道被以不規(guī)則的形狀挖掘。邊墻的煤卻是又軟又松，很容易掉下來。巷道周圍的巖石不是很穩(wěn)定，頂和邊墻易于倒下或者斷裂，這對(duì)于煤炭生產(chǎn)和礦工的安全都是一個(gè)隱患。工作進(jìn)程經(jīng)常由于巷道的困難得維護(hù)而停止。</p><p>　　1.2用離散元素法來仿真巷道的變形和失效</p><p>　　接縫的統(tǒng)計(jì)結(jié)果表明巷道的圍巖是被兩個(gè)垂直的接縫破壞的，一條是煤礦測(cè)量的基床，另一條是垂直

71、于基床的，主要發(fā)生在緊鄰的頂。由于緊鄰頂?shù)牡蛷?qiáng)度，常常會(huì)出現(xiàn)穿透緊鄰頂?shù)拈L(zhǎng)裂縫。這么長(zhǎng)的裂縫是冒頂事故發(fā)生的主要原因。按照裂縫的空間分布，建立起一個(gè)如圖1的離散元素模型，計(jì)算所需要的參數(shù)主要基于現(xiàn)場(chǎng)的測(cè)量和一些后續(xù)的分析，模型實(shí)際的負(fù)載是重力。這些離散元素是完全可變的，因此巖石的變形可以被考慮在內(nèi)。</p><p>　　當(dāng)巷道被挖掘好以后，在處應(yīng)力的作用下，上方邊墻的煤層首先破裂，接著下方邊墻的煤層的表面開始屈服

72、變形。結(jié)果兩個(gè)邊墻的間的頂?shù)闹巫兂缮顚拥膱?jiān)實(shí)的煤層，在巷道表面的緊鄰的頂開始彎曲變形，基床分離，失效并且掉落（如圖2），結(jié)果大面積的頂?shù)袈?，直到到主頂。?dāng)一個(gè)小震動(dòng)發(fā)生時(shí)，一些破碎的巖石可能倒塌。實(shí)際上，掉落的巖石很難處理，有時(shí)如果沒有特別關(guān)注，上方緊鄰頂可能會(huì)發(fā)生一系列倒塌，那會(huì)使掉落巖石的處理成為一項(xiàng)困難并且危險(xiǎn)的任務(wù)。</p><p>　　圖1 離散元素模型的巖石分割 圖2 巷道周圍圍

73、巖的狀況</p><p>　　結(jié)果表明兩個(gè)邊墻煤層的失效是不同的，上方的煤層比下方煤層更容易破裂。</p><p>　　按照上面提到的分析，可以看出在中間對(duì)于低的薄硬傾斜煤層，兩個(gè)邊墻煤層的穩(wěn)定性對(duì)于整個(gè)巷道的穩(wěn)定性是非常重要的。如果邊墻失效，接著頂?shù)闹螌?huì)變成深層的堅(jiān)實(shí)的煤層，結(jié)果頂?shù)淖杂煽缇嘣黾?，這樣會(huì)加大整個(gè)巷道的不穩(wěn)定性。當(dāng)受到采煤的影響時(shí)，圍巖的失效會(huì)更嚴(yán)重。這樣保證整個(gè)傾斜煤

74、層巷道的穩(wěn)定性的關(guān)鍵就是保證邊墻的堅(jiān)實(shí)和完整。</p><p>　　2 巷道周圍的松動(dòng)區(qū)域的測(cè)量</p><p>　　基于松動(dòng)區(qū)域的挖掘理論，一個(gè)松動(dòng)區(qū)域通常在挖掘的洞的周圍形成，因?yàn)槟堑膽?yīng)力比初應(yīng)力低。由于傾斜煤層巷道的不規(guī)則形狀和各向異性的媒介，在巷道周圍的松動(dòng)區(qū)域也是不規(guī)則的形狀。我們使用一種超聲波裂縫探測(cè)儀（撫順煤炭科學(xué)和技術(shù)學(xué)院研發(fā)的型號(hào)為SC-II）來測(cè)量巷道的松動(dòng)區(qū)域，測(cè)試結(jié)

75、果如圖3所示。巷道被兩個(gè)到頂?shù)?.6米的錨噴支護(hù)支撐，錨噴支護(hù)內(nèi)有一點(diǎn)混凝土預(yù)應(yīng)力。被測(cè)量的松動(dòng)區(qū)域是上方邊墻煤層高1.8米，下方邊墻煤層低1.4到1.5米，并且頂?shù)母叨仁?.95到1.1米。</p><p>　　圖3 傾斜煤層巷道周圍松動(dòng)區(qū)域的結(jié)果</p><p>　　巷道在沒有開采影響下可以是穩(wěn)定的，但是只要受到開采的影響，巷道將會(huì)由于邊墻的失效和頂?shù)牡袈涠顾Ｔ谧罱K的情況下，最大的

76、采礦高度可以達(dá)到4.0米。</p><p>　　因此傾斜煤層的巷道很難維護(hù)，而且維護(hù)費(fèi)用非常高。測(cè)試的結(jié)果是符合數(shù)值計(jì)算的，所以加固包括邊墻在內(nèi)的巷道是非常必要的。</p><p>　　3錨桿頂?shù)膬A斜組合橫梁的模型</p><p>　　在傾斜煤層中，當(dāng)錨桿的長(zhǎng)度小于軟且松動(dòng)的頂時(shí)，錨桿頂將傾斜的頂聯(lián)合起來。當(dāng)然如果錨桿可以支撐到一個(gè)合適的地層，那么錨桿裝置將會(huì)掛在上

77、面。一種典型的傾斜組合橫梁模型如圖4所示。橫梁是由幾個(gè)（層的總數(shù)為k）不同性質(zhì)的長(zhǎng)度為L(zhǎng)且厚度為地層組成的。有如下假設(shè)（1）每一層的橫梁是均勻的、連續(xù)的、各向同性的；（2）橫梁屈服于小的變形；（3）每一層同時(shí)變形，且沒有在基面上的滑動(dòng)。</p><p>　　圖4 傾斜組合橫梁的錨桿頂模型</p><p>　　按照橫梁的標(biāo)準(zhǔn)強(qiáng)度，組合橫梁最小的厚度可以被得出，并且錨桿的</p>

78、<p>　　總長(zhǎng)度可以被容易的確定如下：</p><p><b>　?。?）</b></p><p>　　這里是錨桿的長(zhǎng)度；是伸出部分的長(zhǎng)度</p><p>　　由錨桿不會(huì)沿著基床滑動(dòng)的規(guī)律，錨桿間距a可以得出。除了以上提到的條件，組合橫梁的安全性一定要被檢查，以保證它的縱向的穩(wěn)定性。</p><p>　　當(dāng)

79、所有的條件都具備了，錨桿頂參數(shù)就可以被確定了。至于邊墻的錨桿，它們的長(zhǎng)度和間距可以由巖土力學(xué)中的巖土支撐理論得出。</p><p>　　當(dāng)頂是由不牢固和松軟的地層構(gòu)成時(shí)，一定要實(shí)施一些支撐的措施，來保護(hù)易碎頂?shù)耐暾浴?lt;/p><p>　　4 巷道的錨桿支護(hù)及其評(píng)定</p><p>　　4.1 離散元素法的支撐評(píng)定</p><p>　　我們考

80、慮到兩種情形來比較，一種是只有頂被錨桿支護(hù)；另一種是頂和邊墻都被支護(hù)。</p><p>　　使用第一種情形的支護(hù)，在初期頂板明顯要承受更高的應(yīng)力，只有輕微的偏差發(fā)生。然而隨著邊墻煤的掉落和開采，頂板的自由跨距在增加，頂板逐漸進(jìn)入不穩(wěn)定階段，下沉和基床的分離如圖5所示。同無支撐的巷道相比，經(jīng)過錨桿支護(hù)的頂板的巷道可以在一個(gè)比較長(zhǎng)的時(shí)間內(nèi)保持穩(wěn)定，甚至到它最終動(dòng)搖。</p><p>　　在第二

81、種情形，邊墻煤層的變形和失效被邊墻的錨桿嚴(yán)格控制，邊墻是穩(wěn)定的。頂板只偏轉(zhuǎn)了一個(gè)很小的角度。在如圖6所示的巖層圖表中幾乎看不到位移。整個(gè)周圍的地層處在穩(wěn)定的條件下，哪怕受到開采的影響，巷道只會(huì)局部的失效，頂板還是相當(dāng)穩(wěn)定。因此采用一種全面的包括邊墻錨桿支護(hù)形式是非常重要的。</p><p>　　圖5 當(dāng)只有頂板被錨桿支護(hù)時(shí)的周圍地層的運(yùn)動(dòng)</p><p>　　圖6 當(dāng)采用全面支護(hù)時(shí)頂板的穩(wěn)

82、定性</p><p>　　4.2錨桿支護(hù)的方案及其應(yīng)用</p><p>　　基于傾斜的組合橫梁理論，巷道松動(dòng)區(qū)域的測(cè)量和離散元素分析，在頂板上安裝四根1.6米長(zhǎng)的錨桿。在每一根錨桿外部的末端，安裝了一種測(cè)試裝置（中國(guó)國(guó)家專利局的專利）來確保錨桿最少能承受20kN的負(fù)載。錨桿間距是0.75米，排列斜度是1.0米。對(duì)于已經(jīng)形成的裂縫，鋼結(jié)構(gòu)同錨桿頂板一起使用，來保證支撐應(yīng)力和預(yù)防局部頂板掉落。

83、鋼板是0.01米厚，0.89米長(zhǎng)和0.1米寬。</p><p>　　邊墻的煤層被間距是1.0米的木料錨桿加固，木料錨桿對(duì)于上方邊墻是2.0米長(zhǎng)，下方邊墻是1.0米長(zhǎng)。木料錨桿安裝好后，則不會(huì)少于7.5kN的負(fù)載。</p><p>　　對(duì)于前面的鄰接壓力所影響的區(qū)域，增加了加固支護(hù)。有木料蓋的金屬磨擦支撐被作為臨時(shí)加固。加固的距離是在工作面前方25米。加固物被排列在巷道的中心線上。</

84、p><p>　　更多的關(guān)注應(yīng)該投向巷道的挖掘過程。頂板的錨桿支護(hù)要在頂板露出后馬上完成，接著是邊墻支護(hù)。最多延遲時(shí)間不要超過6個(gè)小時(shí)，否則將會(huì)使頂板變形嚴(yán)重且完整性降低。等到每一個(gè)工程周期結(jié)束，靠近推進(jìn)面的錨桿要被再次固定，來保證它們的固定能力。</p><p>　　4.3 巷道的最終測(cè)試</p><p>　　為了評(píng)定支護(hù)方案的效果，在巷道的推進(jìn)和工作面的撤退過程中，巷

85、道就被監(jiān)測(cè)起來。</p><p>　　頂板對(duì)于基床、邊墻和頂板的下沉速度如圖7所示，可以看出當(dāng)工作面距離測(cè)量區(qū)域很遠(yuǎn)時(shí)，圍巖的變形是非常小的，這表明巷道不是受工作面的變應(yīng)力的影響的，支撐體系可以很容易的承受巷道本身的靜應(yīng)力。隨著工作面的推進(jìn)，巷道開始受到工作面變應(yīng)力的影響。</p><p>　　圖7 巷道中圍巖失效過程</p><p>　　當(dāng)工作面與監(jiān)測(cè)區(qū)域間的距離

86、是大約20米時(shí)，圍巖的變形速度明顯增加，而且底層運(yùn)動(dòng)明顯。巷道的這些變化是因?yàn)楣ぷ髅娴膭?dòng)力作用。測(cè)試結(jié)果表明加固距離要大于20米。然而從整個(gè)圍巖的底層來看，巷道是處在穩(wěn)定的條件下，并且可以滿足煤炭安全運(yùn)輸、通風(fēng)口和其他工程功能的要求。</p><p>　　事實(shí)上盡管頂板上有兩到三條明顯的裂縫，但在頂板錨桿和鋼結(jié)構(gòu)的組合作用下，頂板仍是穩(wěn)定的。上方邊墻煤層失效而且掉落在某些地方，但深度控制在0.6米。</p&

87、gt;<p>　　簡(jiǎn)單扼要地講，基于這些情況，這種支護(hù)方案是合理有效的。在經(jīng)濟(jì)和技術(shù)方面獲得很好的益處。</p><p><b>　　5 結(jié)論</b></p><p>　　傾斜煤層的巷道失效形式是顯著不同的。失效的區(qū)域不只是與地層的機(jī)械性質(zhì)有關(guān)，而且與邊墻煤層的穩(wěn)定性有密切關(guān)系。邊墻煤層的失效導(dǎo)致支撐點(diǎn)轉(zhuǎn)移到深層堅(jiān)實(shí)的煤層，增加了頂板的自由間距和破壞了頂

88、板的完整性。因此在巷道的維護(hù)中關(guān)鍵是要保證巷道邊墻的穩(wěn)定性。 </p><p>　　通過巷道松動(dòng)區(qū)域測(cè)試，用傾斜的組合橫梁模型，錨桿支護(hù)參數(shù)可以確定。離散元素法可以被采用來檢驗(yàn)合理性，并做一些改善。對(duì)于有多重松軟地層的頂板，保證錨桿的負(fù)載和盡量早的進(jìn)行頂板錨桿支護(hù)是使頂板穩(wěn)定的關(guān)鍵。同時(shí)用鋼結(jié)構(gòu)（有時(shí)金屬網(wǎng)也需要）來使頂板完整是另一種重要的措施。事實(shí)證明，錨桿支護(hù)用于易碎且不牢固的頂板支撐是一種必要的措施，可以

89、獲得可觀的經(jīng)濟(jì)效益。</p><p><b>　　英文參考文獻(xiàn)</b></p><p>　　1 陶連金. 大傾角煤層開采礦山壓力顯現(xiàn)及其控制：[學(xué)位論文] 沈陽(yáng)：東北大學(xué) 1996.70～79</p><p>　　2侯朝炯，郭宏亮. 我國(guó)煤巷錨桿技術(shù)的發(fā)展方向：煤炭學(xué)報(bào) 1996.21(2):113～118</p><p&

90、gt;　　3 陳炎光主編 中國(guó)煤礦巷道圍巖控制 徐州：中國(guó)礦業(yè)大學(xué)出版社 1995.1～25</p><p>　　4 陶連金. 寶山煤礦巷道圍巖松動(dòng)范圍測(cè)試建井技術(shù).1993(3-4):67～70</p><p>　　5劉明遠(yuǎn)，陶連金，李芳成等 錨桿預(yù)緊力標(biāo)示圈. 1993，國(guó)家專利號(hào)：93208997.6</p><p>　　6 張倬元，王士天. 工程動(dòng)力地質(zhì)學(xué)