岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
4期
913-918,925
,共7页
周辉%孟凡震%卢景景%张传庆%杨凡杰
週輝%孟凡震%盧景景%張傳慶%楊凡傑
주휘%맹범진%로경경%장전경%양범걸
起裂强度%损伤强度%声发射%体积应变刚度%计算方法
起裂彊度%損傷彊度%聲髮射%體積應變剛度%計算方法
기렬강도%손상강도%성발사%체적응변강도%계산방법
crack initiation strength%crack damage strength%acoustic emission%volumetric strain stiffness%calculating method
岩石裂纹起裂强度?ci和损伤强度?cd的研究对探讨岩石渐进破坏过程和脆性破坏机制,建立岩石的起裂强度和长期强度准则具有重要意义。鉴于此,系统总结了岩石起裂强度和损伤强度的4种计算方法,包括裂纹应变模型计算法,声发射参数取值法,侧向应变、体积应变曲线观察法和移动点回归法,并以大理岩和花岗岩在单轴压缩条件下为例,详细描述了用不同方法计算?ci和?cd时存在的问题。研究结果表明,裂纹应变模型法物理意义明确,可以方便和准确地确定岩石的?ci和cd?;声发射撞击率可以定性或半定量了解岩石的渐进破坏和损伤过程,但无法准确定量确定?ci和?cd;移动点回归法计算体积应变刚度时受取值点间隔影响较大,而且加载过程中不同阶段的特征并不明显,难以确定起裂强度值。研究结论可为加深对岩石裂纹起裂强度和损伤强度的重要意义的认识,了解两个强度值的计算方法并合理选取其计算方法提供有益的参考。
巖石裂紋起裂彊度?ci和損傷彊度?cd的研究對探討巖石漸進破壞過程和脆性破壞機製,建立巖石的起裂彊度和長期彊度準則具有重要意義。鑒于此,繫統總結瞭巖石起裂彊度和損傷彊度的4種計算方法,包括裂紋應變模型計算法,聲髮射參數取值法,側嚮應變、體積應變麯線觀察法和移動點迴歸法,併以大理巖和花崗巖在單軸壓縮條件下為例,詳細描述瞭用不同方法計算?ci和?cd時存在的問題。研究結果錶明,裂紋應變模型法物理意義明確,可以方便和準確地確定巖石的?ci和cd?;聲髮射撞擊率可以定性或半定量瞭解巖石的漸進破壞和損傷過程,但無法準確定量確定?ci和?cd;移動點迴歸法計算體積應變剛度時受取值點間隔影響較大,而且加載過程中不同階段的特徵併不明顯,難以確定起裂彊度值。研究結論可為加深對巖石裂紋起裂彊度和損傷彊度的重要意義的認識,瞭解兩箇彊度值的計算方法併閤理選取其計算方法提供有益的參攷。
암석렬문기렬강도?ci화손상강도?cd적연구대탐토암석점진파배과정화취성파배궤제,건립암석적기렬강도화장기강도준칙구유중요의의。감우차,계통총결료암석기렬강도화손상강도적4충계산방법,포괄렬문응변모형계산법,성발사삼수취치법,측향응변、체적응변곡선관찰법화이동점회귀법,병이대리암화화강암재단축압축조건하위례,상세묘술료용불동방법계산?ci화?cd시존재적문제。연구결과표명,렬문응변모형법물리의의명학,가이방편화준학지학정암석적?ci화cd?;성발사당격솔가이정성혹반정량료해암석적점진파배화손상과정,단무법준학정량학정?ci화?cd;이동점회귀법계산체적응변강도시수취치점간격영향교대,이차가재과정중불동계단적특정병불명현,난이학정기렬강도치。연구결론가위가심대암석렬문기렬강도화손상강도적중요의의적인식,료해량개강도치적계산방법병합리선취기계산방법제공유익적삼고。
Strength thresholds of crack initiation (?ci ) and crack damage (?cd ) of hard rock are of great significance not only for understanding the progressive failure process and brittle failure mechanism but also for establishing the crack initiation strength criterion and long-term strength criterion. In view of this, four methods to calculate the crack initiation and damage strength, including crack volumetric strain model, acoustic emission method, lateral strain and volumetric strain observation method, moving point regression technique, are summarized systematically;and marble and granite in uniaxial stress state are taken as examples to show problems in determining ci? and cd? by each method. Results show that ci? and cd? can be obtained conveniently and precisely through crack volumetric strain model which has a clear physical meaning;progressive failure and damage process of rock can be comprehended qualitatively or semi-quantitatively by analysis of acoustic emission hit rate; but ci? and cd? can not be acquired accurately. Curve of volumetric strain stiffness is strongly influenced by data intervals and characteristics of different stages during loading are not obvious when moving point regression technique is used, which makes the determination of ci? difficult. The result could contribute to understanding the importance and calculating methods of crack initiation and damage strength thresholds and provide a useful reference to choose appropriate calculating method.