【摘要】：我國(guó)西部礦區(qū)普遍賦存有傾角介于35°～55°之間的大傾角煤層。與近水平或緩斜煤層不同,大傾角工作面老頂巖層沿走向和傾向都能形成鉸接結(jié)構(gòu)。頂板的傾向結(jié)構(gòu)和走向結(jié)構(gòu)對(duì)支架載荷都有顯著影響,屬于空間結(jié)構(gòu)問題。關(guān)于大傾角工作面支架載荷確定的研究,普遍接受的觀點(diǎn)是支架除承擔(dān)頂煤和直接頂載荷外,還要承擔(dān)老頂?shù)牟糠州d荷,但老頂載荷如何準(zhǔn)確計(jì)算是一個(gè)難題。實(shí)踐表明,大傾角煤層直接頂垮落后,沿工作面滾落,不均勻的充填下部頂板,造成大傾角工作面頂板結(jié)構(gòu)與支架載荷具有分區(qū)特征。而針對(duì)大傾角煤層群綜放開采頂板結(jié)構(gòu)與支架載荷的研究較少。本文以王家山煤礦工程地質(zhì)和開采技術(shù)條件為背景,利用現(xiàn)場(chǎng)實(shí)測(cè)、物理模擬、數(shù)值模擬和理論分析等多種手段,研究了大傾角煤層群綜放采場(chǎng)頂板結(jié)構(gòu)與支架載荷關(guān)系。在物理模擬的基礎(chǔ)上,建立了沿傾向和走向的頂板結(jié)構(gòu)力學(xué)模型,3DUC數(shù)值模擬印證了物理模擬的結(jié)論。通過理論分析得到了大傾角煤層群綜放采場(chǎng)中,上煤層及下煤層工作面支架載荷的計(jì)算公式。給出了兼顧支架防滑與抗中區(qū)頂壓的額定工作阻力判據(jù),通過開采實(shí)踐驗(yàn)證了結(jié)論的可靠性。研究表明:大傾角煤層群上煤層開采后,關(guān)鍵層巖塊沿傾向形成鉸接結(jié)構(gòu),受頂板鉸接結(jié)構(gòu)和煤層傾角影響,頂板垮落高度減小,工作面支架的最大載荷為中區(qū)頂壓。下煤層開采后,間隔層整體發(fā)生撓曲下沉,但關(guān)鍵層結(jié)構(gòu)依然穩(wěn)定。支架工作阻力在滿足防止支架側(cè)滑的前提下,主要承擔(dān)頂煤、間隔層與上煤層垮落頂板的載荷。定義垂直于支架頂梁的載荷為“頂壓”,支架間沿傾向傳遞的載荷為“側(cè)壓”,工作面支架頂壓和側(cè)壓存在分區(qū)特征。上區(qū)支架頂壓不大,支架易發(fā)生失穩(wěn):中區(qū)支架承受的頂壓最大,額定工作阻力需要大于頂壓,同時(shí)滿足初撐力自穩(wěn)條件:下區(qū)充填程度最好,頂板結(jié)構(gòu)穩(wěn)定,支架載荷不大,因此下煤層工作支架工作阻力以平衡中區(qū)頂壓的條件來確定。通過實(shí)例驗(yàn)證,表明研究結(jié)果可靠,可為大傾角煤層綜放開采頂板控制提供理論依據(jù)。
[Abstract]:Large dip coal seams with dip angle between 35 擄and 55 擄are commonly found in western mining areas of China. Different from the near horizontal or gently inclined coal seam, the main roof strata of large inclined face can form hinged structure along the direction and tendency. The inclined structure and strike structure of roof have significant influence on the load of support, which belongs to the problem of space structure. It is generally accepted that the support load should bear part of the main roof in addition to the top coal and direct top load, but how to calculate the main roof load accurately is a difficult problem. The practice shows that the roof structure and support load of the large inclined coal face are zoned because of the falling down along the working face and the uneven filling of the lower roof. However, there are few researches on roof structure and support load of fully mechanized caving mining in large inclined coal seam group. Based on the engineering geology and mining technical conditions of Wangjiashan coal mine, this paper studies the relationship between roof structure and support load in fully mechanized caving stope of large inclined coal seam group by means of field measurement, physical simulation, numerical simulation and theoretical analysis. On the basis of physical simulation, the model of roof structure mechanics along the tendency and trend is established. The conclusion of the physical simulation is confirmed by the numerical simulation of 3DUC. Based on the theoretical analysis, the formulas for calculating the support load in the top coal seam and the lower coal face in the fully mechanized caving stope with large dip coal seam are obtained. The criterion of rated working resistance is given, which takes into account both anti-skid and anti-top pressure of support, and the reliability of the conclusion is verified by mining practice. The research shows that after mining the upper coal seam of large dip coal seam group, the key strata rock block forms hinged structure along the inclination, which is affected by roof hinge structure and coal seam dip angle, the roof collapse height is reduced, and the maximum load of the support in the working face is the middle area top pressure. After the coal seam is mined, the whole interval layer is deflection and subsidence, but the structure of the key layer is still stable. The working resistance of the support mainly bears the load of top coal, spacer and upper coal seam caving roof under the premise of preventing the side slip of the support. The load perpendicular to the top beam of the support is defined as "top pressure", and the load transmitted along the inclination between the supports is "lateral pressure". The top pressure of the upper support is small, the support is vulnerable to instability: the top pressure of the central support is the largest, the rated working resistance needs to be greater than the top pressure, and the self-stability condition of the initial support force is satisfied: the filling degree of the lower area is the best, the roof structure is stable, and the load of the support is not large. Therefore, the working resistance of the working support in the lower coal seam is determined by the condition of balancing the top pressure in the middle area. The experimental results show that the research results are reliable and can provide a theoretical basis for roof control of fully mechanized caving mining in large inclined coal seam.
【學(xué)位授予單位】：西安科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TD327.2;TD355

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 王家臣;趙兵文;趙鵬飛;楊勝利;安建華;江志義;;急傾斜極軟厚煤層走向長(zhǎng)壁綜放開采技術(shù)研究[J];煤炭學(xué)報(bào);2017年02期

2 羅生虎;伍永平;劉孔智;解盤石;郎丁;;大傾角煤層長(zhǎng)壁開采空間應(yīng)力拱殼形態(tài)研究[J];煤炭學(xué)報(bào);2016年12期

3 伍永平;解盤石;王紅偉;任世廣;;大傾角煤層群長(zhǎng)壁采場(chǎng)低位梯階關(guān)鍵層[J];西安科技大學(xué)學(xué)報(bào);2014年06期

4 伍永平;劉孔智;，

本文編號(hào)：2245426