本文選題：裂紋擴(kuò)展 + 數(shù)字散斑��； 參考：《煤炭學(xué)報(bào)》2017年10期

【摘要】：瓦斯抽采鉆孔孔周裂隙漏氣是抽采失效的主要原因之一,孔周裂隙擴(kuò)展在煤體破壞的過程中表現(xiàn)孕育、穩(wěn)定擴(kuò)展及迅速擴(kuò)展3個(gè)階段。為探究孔周裂紋在松軟煤體不同破壞階段的發(fā)展特征,開展含孔試樣漸進(jìn)性破壞過程中的孔周裂紋擴(kuò)展規(guī)律研究。將石膏與水以質(zhì)量比7∶3混合制成類軟煤含孔方形試樣,進(jìn)行單軸壓縮試驗(yàn)并采用數(shù)字散斑相關(guān)測量方法(DSCM)獲取試樣表面全場變形。基于此,提出了利用DSCM系統(tǒng)確定應(yīng)力門檻值的方法,并將其用于含孔試樣漸進(jìn)性破壞過程的孔周變形精細(xì)化分析,利用該方法所確定的應(yīng)力門檻值可將試樣的破壞過程劃分為5個(gè)階段,通過提取與計(jì)算分析試樣表面全場變形數(shù)據(jù),得到在不同階段內(nèi)試樣表面相對位移、以及孔周位移。結(jié)果表明:試樣表面相對位移發(fā)展歷經(jīng)緩慢降低,加速降低以及迅速降低3個(gè)階段,其中加速降低和迅速降低階段與應(yīng)力-應(yīng)變曲線的裂紋穩(wěn)定擴(kuò)展和裂紋加速擴(kuò)展對應(yīng);在壓縮過程中,由于孔周對稱移動(dòng)造成孔周表面拉伸和壓縮錯(cuò)動(dòng),最終在表面形成主拉伸裂紋和法向剪切裂紋。
[Abstract]:It is one of the main reasons that the gas leakage in the hole in the hole of the gas extraction drilling is one of the main reasons for the failure of the extraction. The expansion of the fracture of the hole in the process of the failure of the coal body shows birth, the steady expansion and the rapid expansion of the 3 stages. The plaster and water are mixed with water with the mass ratio of 7 to 3 to make a square specimen with holes in the soft coal. A single axial compression test and a digital speckle correlation method (DSCM) are used to obtain the total field deformation of the surface of the specimen. Based on this, a method of determining the stress threshold by the DSCM system is proposed and used in the progressive failure of the bore specimen. The failure process of the specimen can be divided into 5 stages by the stress threshold value determined by this method. By extracting and calculating the total field deformation data on the surface of the specimen, the relative displacement of the specimen surface and the displacement of the hole in different stages are obtained. The results show that the relative displacement of the sample surface develops through the development of the specimen surface. Slow reduction, acceleration reduction and rapid reduction of 3 stages, in which the accelerated and rapid reduction stages correspond to the steady crack propagation of the stress strain curve and the acceleration of the crack. In the compression process, the Kong Zhou symmetry movement causes the Kong Zhou surface tension and the compression dislocation, and finally the main tensile crack and the normal shear are formed on the surface. Crackle.

【作者單位】： 西安科技大學(xué)理學(xué)院;西安科技大學(xué)安全科學(xué)與工程學(xué)院;
【基金】：國家自然科學(xué)基金資助項(xiàng)目(51374168,51504189);國家自然科學(xué)基金科學(xué)儀器基礎(chǔ)研究專項(xiàng)資助項(xiàng)目(51327007)
【分類號】：TD712.6
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本文編號：1829356