【摘要】：針對(duì)煤巖破壞前兆信號(hào)的有效性,開展了等效圍壓下的含瓦斯型煤加載試驗(yàn),采集了加載破壞過程中的聲發(fā)射信號(hào),基于臨界慢化原理計(jì)算了聲發(fā)射計(jì)數(shù)-時(shí)間序列的方差和自相關(guān)系數(shù),分析了煤樣破壞的前兆信號(hào).結(jié)果表明:等效圍壓下,含瓦斯煤在壓縮破裂過程中,聲發(fā)射累計(jì)計(jì)數(shù)隨時(shí)間的響應(yīng)經(jīng)歷了初始活躍期、穩(wěn)定增長(zhǎng)期、加速增長(zhǎng)期和峰后衰減期;不同圍壓-孔隙壓力下煤樣壓縮破裂聲發(fā)射特征均存在臨界慢化現(xiàn)象,聲發(fā)射計(jì)數(shù)序列的方差和自相關(guān)系數(shù)在煤樣破壞前均出現(xiàn)了增大并持續(xù)增加的趨勢(shì),可以作為煤樣破壞的前兆信號(hào).相比聲發(fā)射累計(jì)計(jì)數(shù)所表征的前兆信號(hào),縮短了前兆信號(hào)與破壞點(diǎn)之間的時(shí)間差,前兆信號(hào)對(duì)應(yīng)的載荷也更接近試樣所能承受的最大載荷,更加表明試樣確實(shí)進(jìn)入危險(xiǎn)破裂階段.
[Abstract]:Aiming at the validity of the precursor signal of coal and rock failure, the loading test of gas-bearing briquette under equivalent confining pressure is carried out, and the acoustic emission signals during the loading and failure are collected. Based on the critical slowing principle, the variance and autocorrelation coefficient of acoustic emission counting-time series are calculated, and the precursor signals of coal sample destruction are analyzed. The results show that under the equivalent confining pressure, the cumulative acoustic emission (AE) count has experienced the initial active period, the stable growth period, the accelerated growth period and the post-peak attenuation period during the compression rupture of the gas-bearing coal. Under different confining pressure and pore pressure, the characteristics of compression fracture acoustic emission of coal samples have the phenomenon of critical slowing down, and the variance and autocorrelation coefficient of acoustic emission counting series increase and continue to increase before the coal samples are destroyed. It can be used as a precursor signal of coal sample damage. Compared with the precursor signal represented by the cumulative acoustic emission count, the time difference between the precursor signal and the failure point is shortened, and the load corresponding to the precursor signal is closer to the maximum load that the sample can bear. It also shows that the specimen does enter the stage of dangerous rupture.
【作者單位】： 中國(guó)礦業(yè)大學(xué)煤礦瓦斯與火災(zāi)防治教育部重點(diǎn)實(shí)驗(yàn)室安全工程學(xué)院;中國(guó)科學(xué)院武漢巖土力學(xué)研究所;
【基金】：中央高�；究蒲袠I(yè)務(wù)費(fèi)專項(xiàng)資金項(xiàng)目(2014ZDPY23) 江蘇省研究生培養(yǎng)創(chuàng)新工程項(xiàng)目(KYZZ16_0228) 中國(guó)礦業(yè)大學(xué)優(yōu)秀創(chuàng)新團(tuán)隊(duì)項(xiàng)目(2014ZY001)
【分類號(hào)】：TD712;TD32

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1 吳浩;基于臨界慢化現(xiàn)象的氣候突變前兆信號(hào)的研究[D];揚(yáng)州大學(xué);2014年

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