【摘要】：淺埋煤層開采常采用長壁式綜采,全部垮落法管理頂板,這使得巖層移動劇烈,地表沉陷量較大。本文采用理論模型分析、地表沉陷觀測及數(shù)值模擬的研究方法,對淺埋煤層開采后的巖層移動及地表沉陷進(jìn)行了深入研究。淺埋煤層開采后巖層移動無彎曲下沉帶,上覆巖土層呈“三帶”(冒落帶、裂隙帶和松散層)分布。冒落帶緊鄰采空區(qū),隨著煤層開采后立即垮落,且破斷塊度較小。裂隙帶位于冒落帶上側(cè),巖層破斷塊度較大,且在破斷后能保持層狀分布。地表松散層顆粒介質(zhì)較分散,移動具有隨機(jī)介質(zhì)移動的特點(diǎn),并在地表形成沉陷盆地。在冒落帶垮落前,將采空區(qū)簡化為橢圓形洞室,分析得到冒落帶巖層應(yīng)力;隨著煤層的開采,未垮落的冒落帶巖層簡化為懸臂梁,計(jì)算得到冒落帶巖層應(yīng)力,結(jié)合巖層破斷條件得到冒落帶巖層的破斷機(jī)理�？偨Y(jié)破碎巖石的碎脹系數(shù),得到了巖層的沉陷經(jīng)驗(yàn)值。巖層移動中關(guān)鍵層起著重要作用,通過簡化建立了關(guān)鍵層彈性地基梁模型,并求解得到了關(guān)鍵層的彎矩、剪力、撓度和轉(zhuǎn)角的解析解。結(jié)合巖梁破斷條件,得到關(guān)鍵層初次破斷距和周期破斷距。將模型應(yīng)用到實(shí)際工程中,結(jié)果表明關(guān)鍵層彈性地基量模型可較好估算關(guān)鍵層的破斷距。應(yīng)用隨機(jī)介質(zhì)理論得到了單元開采的地表沉陷曲線,并積分得到半無限開采地表沉陷預(yù)測公式。將有限開采視為兩個無限開采之和的1/2,得到了有限開采的地表沉陷預(yù)測公式。對沉陷參數(shù)進(jìn)行回歸分析,得到巖性與沉陷參數(shù)的關(guān)系。對地表沉陷進(jìn)行實(shí)際觀測,獲得了地表沉陷實(shí)測值。對比理論預(yù)測與觀測結(jié)果,兩者吻合程度較高,理論模型可較好應(yīng)用在淺埋煤層地表沉陷預(yù)測中。建立了淺埋煤層開采UDEC模型,模擬分步開采過程,得到巖層移動動態(tài)規(guī)律。對比數(shù)值模擬和觀測成果,兩者的相對誤差較小。這說明數(shù)值模擬可較好應(yīng)用在淺埋煤層地表沉陷預(yù)測中。
[Abstract]:Long-wall fully mechanized mining is often used in shallow coal seam mining, and roof is managed by all caving method, which makes the rock strata move violently and the subsidence amount of the surface is large. In this paper, theoretical model analysis, surface subsidence observation and numerical simulation are used to study the strata movement and surface subsidence after mining in shallow coal seam. After mining in shallow coal seam, the strata move without bending subsidence zone, and the overlying rock layer is distributed as "three zones" (fall zone, fracture zone and loose layer). The caving zone is adjacent to the goaf, and it collapses immediately after coal seam mining, and the breaking block degree is smaller. The fracture zone is located on the upper side of the caving zone. The fracture block degree of the rock layer is large, and the layer distribution can be maintained after the fracture. The granular medium in the surface loose layer is dispersed and has the characteristics of random medium movement, and the subsidence basin is formed on the surface of the earth. Before the caving zone collapses, the goaf is simplified to an oval chamber, and the rock stress in the caving zone is analyzed. With the mining of coal seam, the rock layer of the uncollapsed caving zone is simplified to cantilever beam, the stress of the falling zone is calculated, and the breaking mechanism of the caving zone is obtained by combining the breaking conditions of the strata. The coefficient of crushing expansion of broken rock is summarized, and the experiential value of rock subsidence is obtained. The key layer plays an important role in rock movement. By simplifying the elastic foundation beam model of the key layer, the analytical solutions of bending moment, shear force, deflection and rotation angle of the key layer are obtained. Combined with the rock beam breaking conditions, the initial breaking distance and the periodic breaking distance of the key strata are obtained. The model is applied to practical engineering, and the results show that the elastic foundation model of the key layer can estimate the breaking distance of the critical layer well. The surface subsidence curve of unit mining is obtained by using random medium theory, and the prediction formula of semi-infinite mining surface subsidence is obtained by integral. The finite mining is regarded as the sum of two infinite mining, and the prediction formula of surface subsidence of limited mining is obtained. The relationship between lithology and subsidence parameters is obtained by regression analysis of subsidence parameters. The actual observation of the surface subsidence is carried out, and the measured value of the surface subsidence is obtained. The theoretical prediction and observation results are in good agreement with each other. The theoretical model can be applied to the prediction of surface subsidence in shallow coal seam. The UDEC model of shallow coal seam mining is established to simulate the step-by-step mining process and obtain the dynamic law of strata movement. Compared with the results of numerical simulation and observation, the relative error between them is relatively small. This shows that the numerical simulation can be applied to the prediction of surface subsidence in shallow coal seam.
【學(xué)位授予單位】：西安科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TD325

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 公茂旭;陳加更;呂國慶;;承壓含水層自身性質(zhì)對地表沉陷的影響規(guī)律[J];煤礦安全;2013年02期

2 官凱;董濤;賈金龍;;基于UDEC的淺埋煤層表土層與主關(guān)鍵層對地表沉陷的耦合效應(yīng)分析[J];煤礦安全;2012年03期

3 繆協(xié)興;張吉雄;郭廣禮;;綜合機(jī)械化固體充填采煤方法與技術(shù)研究[J];煤炭學(xué)報(bào);2010年01期

4 朱衛(wèi)兵;許家林;施喜書;王曉振;劉文濤;;覆巖主關(guān)鍵層運(yùn)動對地表沉陷影響的鉆孔原位測試研究[J];巖石力學(xué)與工程學(xué)報(bào);2009年02期

5 滕永海;王金莊;;綜采放頂煤地表沉陷規(guī)律及機(jī)理[J];煤炭學(xué)報(bào);2008年03期

6 湯伏全;姚頑強(qiáng);夏玉成;;薄基巖下淺埋煤層開采地表沉陷預(yù)測方法[J];煤炭科學(xué)技術(shù);2007年06期

7 季翔;伍佑倫;李江武;;崩落法開采時復(fù)雜頂板的崩落過程分析[J];金屬礦山;2007年04期

8 許家林;尤琪;朱衛(wèi)兵;李興尚;賴文奇;;條帶充填控制開采沉陷的理論研究[J];煤炭學(xué)報(bào);2007年02期

9 譚志祥,鄧喀中,白振明,王宗盛,孫新民;綜放開采地表移動變形規(guī)律實(shí)測研究[J];測繪通報(bào);2003年09期

10 蔣建平,高廣運(yùn);地下工程引起的不均衡地表沉陷分析[J];煤炭學(xué)報(bào);2003年03期

相關(guān)博士學(xué)位論文 前1條

1 黃平路;構(gòu)造應(yīng)力型礦山地下開采引起巖層移動規(guī)律的研究[D];中國科學(xué)院研究生院（武漢巖土力學(xué)研究所）;2008年

相關(guān)碩士學(xué)位論文 前3條

1 洪興;淺埋煤層開采引起的地表移動規(guī)律研究[D];西安科技大學(xué);2012年

2 王云廣;五陽礦淺埋厚煤層開采地表沉陷規(guī)律研究及系統(tǒng)開發(fā)[D];河南理工大學(xué);2012年

3 劉文濤;采場覆巖移動流變模型及開采沉陷預(yù)計(jì)研究[D];太原理工大學(xué);2004年

，

本文編號：2457113