岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2013年
11期
3180-3186
,共7页
黄曼%杜时贵%罗战友%倪骁慧
黃曼%杜時貴%囉戰友%倪驍慧
황만%두시귀%라전우%예효혜
不同尺寸%岩石模型结构面%直剪试验%抗剪强度
不同呎吋%巖石模型結構麵%直剪試驗%抗剪彊度
불동척촌%암석모형결구면%직전시험%항전강도
different sizes%simulation rock structural plane%direct shear test%shear strength
开展岩石模型结构面抗剪强度特征的多尺度(尤其大尺寸)直剪试验研究对于理解岩石结构面力学特性具有重要的理论价值和实践意义。首先,基于多尺度直剪试验仪(MSJ-DST),对20 cm×20 cm、40 cm×40 cm、60 cm×60 cm、80 cm×80 cm和100 cm×100 cm的岩石模型结构面试样采用法向应力分别为200~1000 kPa进行直接剪切试验;然后,研究不同尺寸岩石模型结构面抗剪强度的特征。结果表明:不同法向荷载作用下模型的受力变形特点相近,峰值剪切位移总体上随着某一数值附近上下浮动;在同一法向应力作用下,不同尺寸结构面试样的峰值抗剪强度表现出在某一数值附近上下浮动的特征,残余抗剪强度则表现出随尺寸的增加有小幅度增加;5级法向应力作用下,不同尺寸的峰值抗剪强度和残余抗剪强度随着法向应力的变化规律均近似相同,抗剪强度残余值与峰值的比值随着法向应力的增大逐渐增大并趋于稳定。
開展巖石模型結構麵抗剪彊度特徵的多呎度(尤其大呎吋)直剪試驗研究對于理解巖石結構麵力學特性具有重要的理論價值和實踐意義。首先,基于多呎度直剪試驗儀(MSJ-DST),對20 cm×20 cm、40 cm×40 cm、60 cm×60 cm、80 cm×80 cm和100 cm×100 cm的巖石模型結構麵試樣採用法嚮應力分彆為200~1000 kPa進行直接剪切試驗;然後,研究不同呎吋巖石模型結構麵抗剪彊度的特徵。結果錶明:不同法嚮荷載作用下模型的受力變形特點相近,峰值剪切位移總體上隨著某一數值附近上下浮動;在同一法嚮應力作用下,不同呎吋結構麵試樣的峰值抗剪彊度錶現齣在某一數值附近上下浮動的特徵,殘餘抗剪彊度則錶現齣隨呎吋的增加有小幅度增加;5級法嚮應力作用下,不同呎吋的峰值抗剪彊度和殘餘抗剪彊度隨著法嚮應力的變化規律均近似相同,抗剪彊度殘餘值與峰值的比值隨著法嚮應力的增大逐漸增大併趨于穩定。
개전암석모형결구면항전강도특정적다척도(우기대척촌)직전시험연구대우리해암석결구면역학특성구유중요적이론개치화실천의의。수선,기우다척도직전시험의(MSJ-DST),대20 cm×20 cm、40 cm×40 cm、60 cm×60 cm、80 cm×80 cm화100 cm×100 cm적암석모형결구면시양채용법향응력분별위200~1000 kPa진행직접전절시험;연후,연구불동척촌암석모형결구면항전강도적특정。결과표명:불동법향하재작용하모형적수력변형특점상근,봉치전절위이총체상수착모일수치부근상하부동;재동일법향응력작용하,불동척촌결구면시양적봉치항전강도표현출재모일수치부근상하부동적특정,잔여항전강도칙표현출수척촌적증가유소폭도증가;5급법향응력작용하,불동척촌적봉치항전강도화잔여항전강도수착법향응력적변화규률균근사상동,항전강도잔여치여봉치적비치수착법향응력적증대축점증대병추우은정。
It has important value of theory and practical significance to understand the mechanical characteristics of rock structural planes by taking direct shear tests for shear strength of simulation rock structural planes with different sizes (especially large sizes). Based on MSJ-DST, the direct shear tests of simulation rock structural planes in sizes 20 cm×20 cm, 40 cm×40 cm, 60 cm×60 cm, 80 cm×80 cm and 100 cm×100 cm are taken under the normal stresses from 200 kPa to 1 000 kPa. Then, the characteristics of shear strength of rock structural planes with different sizes are studied. The results indicate that the stresses and deformation characteristics of simulation rock structural planes under different normal stresses are similar; and the peak shear displacements are generally fluctuated in the vicinity of a certain value. Under the same normal stress, the peak shear strength values of simulation rock structural planes with different sizes are fluctuated in the vicinity of a certain value;and the residual shear strength values rise slightly as the size increases. Under five grade normal stresses, the variations of peak shear strength and residual shear strength with different sizes are approximately same;and the ratio of residual shear strength value and peak shear strength value increases and tends to be stable as normal stress increases.