本文關(guān)鍵詞： 淺埋煤層 頂板突水 固液耦合實(shí)驗(yàn) 隔水土層 導(dǎo)水裂縫　出處：《西安科技大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：本論文以榆神府礦區(qū)為研究背景,通過理論分析、物理相似模擬實(shí)驗(yàn)和數(shù)值模擬相結(jié)合的方法,對淺埋煤層上覆隔水土層受采動(dòng)影響的穩(wěn)定性以及隔水性等問題進(jìn)行研究,為礦井突水預(yù)測提供了依據(jù),研究結(jié)果對礦井安全生產(chǎn)具有一定的理論意義。針對三趾馬紅土的物理力學(xué)性質(zhì)、水理性質(zhì),利用土力學(xué)相關(guān)知識對三趾馬紅土性質(zhì)進(jìn)行試驗(yàn)分析,為相似模擬和數(shù)值模擬的進(jìn)一步研究打下基礎(chǔ)。實(shí)驗(yàn)得出三趾馬紅土滲透性隨上覆載荷增大不斷減小,隨水頭壓力增大滲透性增強(qiáng)。以榆神府淺埋煤層、薄基巖、厚土層下的中厚煤層為研究對象,通過固液耦合相似模擬實(shí)驗(yàn)研究隔水土層的下沉與關(guān)鍵層同步運(yùn)動(dòng),由于受到水壓以及水平擠壓作用部分裂縫發(fā)生閉合,在開切眼和工作面上方裂縫發(fā)育較為明顯由于鉸接作用不易閉合;導(dǎo)水裂縫帶的高度受到關(guān)鍵層的影響較為明顯,實(shí)驗(yàn)表明在單一關(guān)鍵層的條件下關(guān)鍵層位置越高導(dǎo)水裂縫帶的發(fā)育高度越低反之亦然。通過紅外成像儀呈現(xiàn)了水的運(yùn)移,表明水在巖層中運(yùn)動(dòng)不僅有縱向運(yùn)動(dòng)還有水平運(yùn)動(dòng)即表現(xiàn)為層流運(yùn)動(dòng)。覆巖上部隔水土層厚度不同隔水效果也不同,土層厚度與采高之比k≤4的條件下,隔水層將發(fā)生不可恢復(fù)的破壞,工作面突水較嚴(yán)重;土層厚度與采高之比4k15的條件下,隔水土層裂縫將會貫通,形成突水通道,但隨著工作面的繼續(xù)推進(jìn)部分裂縫受到水平作用力與水壓共同作用下將會愈合;土層厚度與采高之比k≥15的條件下,隔水土層裂縫不會貫通,不能形成突水通道。應(yīng)用FLAC3D數(shù)值模擬軟件,分析采動(dòng)影響下圍巖的位移場、塑性破壞區(qū)域、孔隙水壓以及滲流等特征,通過對塑性區(qū)、孔隙水壓云圖以及滲流場的分析頂板發(fā)生突水區(qū)域主要集中在開切眼和工作面上方。利用數(shù)值模擬進(jìn)一步驗(yàn)證了淺埋煤層頂板突水是由于隔水土層發(fā)生破壞,導(dǎo)水裂縫帶貫穿隔水土層并溝通含水層而引起。
[Abstract]:In this paper, the Yushenfu mining area as the research background, through theoretical analysis, physical similarity simulation experiment and numerical simulation method combined. This paper studies the stability and water repellency of overlying soil layer affected by mining in shallow coal seam, which provides the basis for the prediction of mine water inrush. The research results have certain theoretical significance for mine safety production. Aiming at the physical and mechanical properties and hydrological properties of the red soil of the third toe horse, the properties of the red soil of the third toe horse are tested and analyzed by using the relevant knowledge of soil mechanics. The experimental results show that the permeability of red soil decreases with the increase of overburden and increases with the pressure of water head. Thin bedrock, thick coal seam under thick soil as the research object, through the solid-liquid coupling simulation experiment to study the subsidence of the impermeable soil and the synchronous movement of the key layer. Due to water pressure and horizontal extrusion, some cracks are closed, and the crack development is obvious because of hinge action is difficult to close in the opening and cutting hole and above the working face. The height of the water-conducting fracture zone is obviously affected by the critical layer. The experimental results show that the higher the position of the critical layer is, the lower the development height of the water-conducting fracture zone is, and vice versa. The water migration is shown by the infrared imager. The results show that the movement of water in rock is not only longitudinal motion but also horizontal movement, that is, laminar movement, the effect of water and soil barrier is different with the ratio of soil thickness to mining height k 鈮，

本文編號：1483283