本文選題：深部煤層　切入點(diǎn)：底板突水　出處：《煤炭科學(xué)研究總院》2015年博士論文

【摘要】：隨著我國礦井淺部煤炭資源開采逐漸枯竭,對深部煤炭資源的開采利用勢在必行。而隨著礦井采掘深度的不斷增加,深部煤層帶水壓開采底板突水的危險(xiǎn)性和危害程度更加嚴(yán)重,這除了與煤層底板承受的含水層水壓力不斷增加的原因之外,還與深部煤層頂、底板圍巖所處的高地應(yīng)力環(huán)境有著密不可分的關(guān)系。怎樣安全有效地把深部煤炭資源從高地應(yīng)力高承壓水開采條件下解放出來,是實(shí)現(xiàn)深部煤炭資源安全開采所面臨的關(guān)鍵技術(shù)難題。在對埋藏深度較淺的煤層實(shí)施帶水壓安全開采的研究工作中,我們通常重點(diǎn)考慮充水水源、充水途徑和充水強(qiáng)度三個(gè)要素,地應(yīng)力大小對工作面底板突水的控制作用以及控制機(jī)理研究較少,甚至忽略不計(jì),但隨著煤層埋深的不斷增加,煤層頂、底板圍巖所受原巖地應(yīng)力迅速增大,圍巖力學(xué)性質(zhì)、采掘擾動(dòng)后的力學(xué)響應(yīng)特征、高壓水作用下的破斷突水機(jī)理都會(huì)產(chǎn)生有別于淺埋煤層的特殊性質(zhì),地應(yīng)力逐漸成為煤層底板突水的重要控制因素。因此,從理論到工程實(shí)際上,系統(tǒng)研究煤層賦存區(qū)原巖地應(yīng)力大小隨埋藏深度的變化規(guī)律,研究深部煤層圍巖所受地應(yīng)力狀態(tài)、高地應(yīng)力對煤層頂?shù)装鍑鷰r力學(xué)性質(zhì)的控制機(jī)理,高地應(yīng)力環(huán)境中煤層底板巖層在采掘擾動(dòng)和水壓力作用下的損傷破壞特征及其對底板高壓水突出的控制作用,進(jìn)而獲得煤層埋藏深度、地應(yīng)力大小與底板突水危險(xiǎn)性評價(jià)指標(biāo)之間的內(nèi)在關(guān)系,是深部煤層開采底板水害形成條件評價(jià)與水害防治的關(guān)鍵科學(xué)與技術(shù)問題,是實(shí)現(xiàn)高地應(yīng)力環(huán)境條件下煤層帶水壓安全開采的重大需求。正是基于上述原因,本論文選擇了“深部煤層開采底板突水地應(yīng)力控制機(jī)理研究”作為主要研究內(nèi)容和研究方向。本論文主要以巖體力學(xué)理論為基礎(chǔ),論述了在不同埋深條件下地應(yīng)力對煤層采掘活動(dòng)中底板擾動(dòng)損傷破壞的控制效應(yīng),分析了地應(yīng)力對底板突水的控制機(jī)理,提出了地應(yīng)力與煤層底板擾動(dòng)損傷破壞深度的量值關(guān)系；通過不同圍壓條件下不同巖性巖石的三軸壓縮試驗(yàn)和滲透性測試試驗(yàn),獲得了巖石強(qiáng)度、變形特征和全應(yīng)力應(yīng)變過程中滲透性變化規(guī)律及量值關(guān)系,分析了圍壓對巖石強(qiáng)度、變形特征、滲透規(guī)律的控制效應(yīng)；通過Flac3D軟件的流固耦合數(shù)值模擬,分析研究了不同埋深條件下煤層回采后底板圍巖應(yīng)力變化特征、塑性變形破壞特征及分布規(guī)律,并對現(xiàn)有突水系數(shù)計(jì)算公式進(jìn)行了修正,同時(shí)提出了深部煤層帶壓開采突水危害程度評價(jià)預(yù)測方法。通過理論分析、實(shí)驗(yàn)研究、數(shù)值模擬和實(shí)測資料統(tǒng)計(jì)分析等研究手段,本文得出以下主要結(jié)論：煤層圍巖垂向地應(yīng)力隨埋藏深度呈遞增變化規(guī)律,垂向地應(yīng)力大小與地層埋深基本成正比關(guān)系；在其它開采條件和開采參數(shù)基本相同的條件下,煤層底板隔水層回采擾動(dòng)損傷破壞深度隨煤層埋深不斷增加而呈現(xiàn)增大趨勢,煤層圍巖地應(yīng)力的大小與煤層開采后工作面底板破壞深度基本成正比關(guān)系,表明地應(yīng)力對煤層底板巖層損傷破壞深度控制效應(yīng)明顯；論文提出了地應(yīng)力影響系數(shù)的概念及其計(jì)算公式：Cd=0.1272△σv+0.8066,并對現(xiàn)有突水系數(shù)計(jì)算公式進(jìn)行了修正：Td=P/M·Cd,同時(shí)提出了深部煤層帶水壓安全開采底板突水危害程度評價(jià)的單位涌水量——突水系數(shù)雙因素(q-Td法)評價(jià)預(yù)測方法。本文研究成果對實(shí)現(xiàn)我國高地應(yīng)力條件下深部煤層帶水壓安全、有序、高效開采具有重要的理論指導(dǎo)意義和實(shí)用價(jià)值。
[Abstract]:Based on the theory of rock mechanics , this paper deals with the control mechanism of rock mechanics property of coal seam roof and bottom plate under the action of mining disturbance and water pressure . It is the key technical problem to realize the safety exploitation of coal seam floor .
Through triaxial compression test and permeability test of different lithologic rocks under different confining pressure conditions , the variation law and magnitude relation of rock strength , deformation characteristics and full stress strain are obtained , and the control effect of confining pressure on rock strength , deformation characteristics and infiltration law is analyzed .
Based on the numerical simulation of fluid - solid coupling of Flac3D software , the characteristics , characteristics and distribution of surrounding rock under different burial conditions are analyzed , and the calculation formula of the existing water inrush system is modified . The main conclusions are as follows : the vertical stress of the surrounding rock of the coal seam increases with the buried depth , and the vertical stress magnitude is directly proportional to the burial depth of the formation .
Under the condition that other mining conditions and mining parameters are basically the same , the damage depth of the back - mining disturbance damage of the coal seam floor is increased with the increasing of the buried depth of the coal seam , and the magnitude of the underground stress of the surrounding rock of the coal seam is basically proportional to the depth of failure of the bottom plate after the coal seam mining , and indicates that the underground stress has obvious control effect on the damage of the coal seam floor rock stratum .
In this paper , the concept and the calculating formula of the influence coefficient of floor stress are presented : Cd = 0.272 鈻，

本文編號(hào)：1720189