(中南大學(xué) 資源與安全工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 討論巖石斷裂力學(xué)研究近年來(lái)的若干進(jìn)展，主要內(nèi)容包括擴(kuò)展機(jī)理、斷裂準(zhǔn)則、實(shí)驗(yàn)加載方式與裂紋定位方法、數(shù)值計(jì)算方法在巖石斷裂力學(xué)研究中的應(yīng)用。基于室內(nèi)實(shí)驗(yàn)研究單軸加載下預(yù)制裂紋間的貫通模式與多裂紋試樣的破壞模式、壓剪復(fù)合作用下混合裂紋間的貫通類型與破碎規(guī)律。與此同時(shí)，針對(duì)巖石亞臨界裂紋擴(kuò)展問(wèn)題進(jìn)行相關(guān)討論并給與實(shí)例分析。結(jié)果表明：處于同一應(yīng)力水平時(shí)，水巖化學(xué)作用能加速亞臨界裂紋擴(kuò)展；水化學(xué)腐蝕后巖石的斷裂韌度均小于其在空氣中的斷裂韌度。此外，還對(duì)巖石流變斷裂模式及考慮原生裂隙的非線性流變模型進(jìn)行分析：結(jié)合巖石斷裂力學(xué)與流變力學(xué)推導(dǎo)出壓剪應(yīng)力環(huán)境下裂紋流變斷裂判據(jù)與理論模型；引入損傷因子和裂隙塑性體構(gòu)建了能描述原生節(jié)理影響的巖體非線性蠕變模型。最后，展望巖石斷裂力學(xué)未來(lái)的發(fā)展前景，并就巖石裂紋萌生與擴(kuò)展的研究闡述幾點(diǎn)認(rèn)識(shí)。
關(guān)鍵字: 裂紋擴(kuò)展；貫通模式；亞臨界擴(kuò)展；流變斷裂；理論模型
（School of Resources and safety engineering, Central South University, Changsha 410083, China）
Abstract:The recent developments in some aspects on the research of rock fracture mechanics were discussed, including the crack extension mechanism, fracture criterion, loading method, locating method of crack and numerical method in rock fracture. At the same time, case studies about crack propagation, subcritical crack growth and creep fracture criterion and theoretical model were accomplished. Firstly, based the uniaxial test of rock-like specimens, the coalescence pattern between fissures and failure modes of multi-fissure specimens was discussed. At the same time, further discussion about the coalescence patterns and fragmentation of mixed crack specimen under compressive-shear test were made. Moreover, the subcritical crack growth, and fracture toughness in three different kinds of nature rocks were investigated with double torsion test. The results show that: at the same stress level, the water-rock interaction can accelerate the subcritical crack growth and the fracture toughness of rocks under atmospheric environment is higher than that of rocks immersed in water. In addition, the creep fracture criterion and nonlinear elastic visco-plastic creep damage models were also analyzed: combined with rock fracture mechanics and rheological mechanics, the theoretical models of crack rheologic fracture failure under compressive-shear load were established. By introducing damage factor and plastic body containing fissures, the nonlinear elastic visco-plastic creep damage model was conducted. Finally, several understandings on the research work were presented in prospect of the fracture mechanics in the future.
Key words: crack propagation; coalescence pattern; subcritical crack growth; rheologic fracture; theoretical model
