岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2014年
7期
1366-1374
,共9页
蒋金泉%张培鹏%聂礼生%李洪%许丽娜%王伟东
蔣金泉%張培鵬%聶禮生%李洪%許麗娜%王偉東
장금천%장배붕%섭례생%리홍%허려나%왕위동
采矿工程%高位硬厚岩层%破断步距%微震活动%地表下沉
採礦工程%高位硬厚巖層%破斷步距%微震活動%地錶下沉
채광공정%고위경후암층%파단보거%미진활동%지표하침
mining engineering%high and thick strata of hard rock%drawing pace of fracturing%microseismicity%subsidence
以杨柳煤矿10416工作面高位硬厚岩浆岩条件为背景,建立高位硬厚岩层三边固支一边简支弹性薄板力学模型,利用瑞利-里兹法,推导出硬厚岩层挠曲函数与应力近似解析式,得到破断跨度的计算式,并根据覆岩破裂形态提出破断步距的计算方法。采用微震、支架压力及地表下沉等监测分析,揭示高位硬厚岩层破断失稳规律及其动力响应。研究表明:高位硬厚岩层破断前的挠度最大点为( x=a/2, y=13b/(10π))(a 为硬厚岩层走向悬露长度,b为硬厚岩层沿倾向的悬露长度);当a<1.049b时,硬厚岩层首先沿倾向固支边发生破断,否则首先沿走向固支边发生破断;硬厚岩层初次破断形式为沿走向对称而沿倾向非对称的“O-X”型,且破断后侧向跨度固支侧大于简支侧。高位硬厚岩层破断及运移过程中微震活动加剧,产生强微震活动,破断失稳期间支架压力显著升高,并引起地表下沉明显变化。高位硬厚岩层破断失稳引起强烈的动力响应,采用理论计算和微震监测可以进行分析预测。
以楊柳煤礦10416工作麵高位硬厚巖漿巖條件為揹景,建立高位硬厚巖層三邊固支一邊簡支彈性薄闆力學模型,利用瑞利-裏玆法,推導齣硬厚巖層撓麯函數與應力近似解析式,得到破斷跨度的計算式,併根據覆巖破裂形態提齣破斷步距的計算方法。採用微震、支架壓力及地錶下沉等鑑測分析,揭示高位硬厚巖層破斷失穩規律及其動力響應。研究錶明:高位硬厚巖層破斷前的撓度最大點為( x=a/2, y=13b/(10π))(a 為硬厚巖層走嚮懸露長度,b為硬厚巖層沿傾嚮的懸露長度);噹a<1.049b時,硬厚巖層首先沿傾嚮固支邊髮生破斷,否則首先沿走嚮固支邊髮生破斷;硬厚巖層初次破斷形式為沿走嚮對稱而沿傾嚮非對稱的“O-X”型,且破斷後側嚮跨度固支側大于簡支側。高位硬厚巖層破斷及運移過程中微震活動加劇,產生彊微震活動,破斷失穩期間支架壓力顯著升高,併引起地錶下沉明顯變化。高位硬厚巖層破斷失穩引起彊烈的動力響應,採用理論計算和微震鑑測可以進行分析預測。
이양류매광10416공작면고위경후암장암조건위배경,건립고위경후암층삼변고지일변간지탄성박판역학모형,이용서리-리자법,추도출경후암층뇨곡함수여응력근사해석식,득도파단과도적계산식,병근거복암파렬형태제출파단보거적계산방법。채용미진、지가압력급지표하침등감측분석,게시고위경후암층파단실은규률급기동력향응。연구표명:고위경후암층파단전적뇨도최대점위( x=a/2, y=13b/(10π))(a 위경후암층주향현로장도,b위경후암층연경향적현로장도);당a<1.049b시,경후암층수선연경향고지변발생파단,부칙수선연주향고지변발생파단;경후암층초차파단형식위연주향대칭이연경향비대칭적“O-X”형,차파단후측향과도고지측대우간지측。고위경후암층파단급운이과정중미진활동가극,산생강미진활동,파단실은기간지가압력현저승고,병인기지표하침명현변화。고위경후암층파단실은인기강렬적동력향응,채용이론계산화미진감측가이진행분석예측。
An elastic model of thin plate with three edges fixed and one simply supported was established as the mechanical model of high and thick strata of hard magmatic rock at working front 10416 in Yangliu coal mine,A flexural function and an analytic expression of stresses for the hard and thick strata were derived with Rayleigh-Ritz method. A formula of fracture span was obtained;and then a method of calculating the length of drawing pace of fracturing according to fracture morphology of overburden was proposed. The analysis of monitored results of microseism,supporting pressures and surface subsidence revealed the fracture process and the dynamic response of high and thick strata of hard rocks. The point of maximum deflection prior to fracturing of strata is at the location of x=a/2 and y=13b/(10π) ,where a is suspension length along the strike of hard-thick strata;b is suspension length along the tendency of hard-thick strata. Fracture first happened along the dip clamper edge if a<1.049b,along the strike clamper edge otherwise. The initial form of fracturing is“O-X” shaped,which is symmetrically along the strike but asymmetrically along the tend. Microseismicity intensified during the process of fracturing and movement of strata leading to the strong microseismicities activities to be generated and the supporting pressure and surface subsidence significantly be increased. Fracturing of high and thick strata of hard rocks causes strong dynamic response which can be analyzed and predicted by theoretical calculation and microseismic monitoring.