安阳膨胀岩重塑样三轴加卸荷试验研究
|
摘要
对取自河南安阳不同深度处的膨胀岩重塑样进行了三轴加载和卸荷试验。结果表明:加载过程中,随着围压的增大,试样的应力应变曲线形态由应变软化型逐渐向应变硬化型转变,峰值强度以及残余强度随围压的增加呈线性增大。不同卸荷量卸荷时,试样的残余强度与卸荷量呈线性正相关,相关系数在0.9左右;峰值强度和弹性模量Eur与卸荷量呈线性负相关,相关系数在0.95左右。循环加卸荷过程中,试样表现出明显的应变软化性质,试样弹性模量Eur随着循环加卸荷次数的增加而增大,且增加幅度越来越小,最终增加幅度趋近于0,稳定弹性模量Eur比初始弹模增加10%左右。因此,在膨胀岩渠道开挖、蓄水及水位降落时,应该考虑其对膨胀岩渠道稳定性的影响。
This paper studies the triaxial test on remolding expansive rock under loading and unloading conditions at different depths of Anyang.The experimental results demonstrate that during the loading process,the stress-strain curve shape of the test samples transform from strain-softening to strain-hardening gradually and the peak strength and residual strength increase linearly with the increase in confining pressure.When unloading weight changes,there is a positive linear relationship between the residual strength of the sample rock and unloading weight with the coefficient of correlation about 0.9,and a negative linear relationship between peak strength,elastic modulus of the sample rock and unloading weight with the coefficient of correlation about 0.95.And,if it is in cyclic loading and unloading process,strain-softening phenomenon is obviously visible in sample rocks.With the increase in cyclic loading and unloading numbers,the elastic modulus decreases,the reduction rate becomes smaller and smaller and disappears in the end,and stable elastic modulus increases about 10% relative to primary.Therefore,the influence of unloading effect on the expansive rock slope stability should be considered in the excavation,storage and the drawdown process of the expansive rock canals.
This paper studies the triaxial test on remolding expansive rock under loading and unloading conditions at different depths of Anyang.The experimental results demonstrate that during the loading process,the stress-strain curve shape of the test samples transform from strain-softening to strain-hardening gradually and the peak strength and residual strength increase linearly with the increase in confining pressure.When unloading weight changes,there is a positive linear relationship between the residual strength of the sample rock and unloading weight with the coefficient of correlation about 0.9,and a negative linear relationship between peak strength,elastic modulus of the sample rock and unloading weight with the coefficient of correlation about 0.95.And,if it is in cyclic loading and unloading process,strain-softening phenomenon is obviously visible in sample rocks.With the increase in cyclic loading and unloading numbers,the elastic modulus decreases,the reduction rate becomes smaller and smaller and disappears in the end,and stable elastic modulus increases about 10% relative to primary.Therefore,the influence of unloading effect on the expansive rock slope stability should be considered in the excavation,storage and the drawdown process of the expansive rock canals.
引文
[1]缪林昌,殷宗泽,刘松玉.非饱和膨胀土强度特性的常规三轴试验研究[J].东南大学学报(自然科学版),2000,30(1):12-125.
[2]缪林昌,殷宗泽.非饱和土的剪切强度[J].岩土力学,1999,20(3):1-6.
[3]缪林昌,崔颖.非饱和土的固结与水力特性研究[J].西北地震学报,2011,33(S1):38-42.
[4]徐永福.非饱和膨胀土结构性强度的研究[J].河海大学学报(自然科学版),1999,27(2):89-92.
[5]李建林.卸荷岩体力学[M].北京:中国水利水电出版社,2003.
[6]邱士利,冯夏庭,张传庆,等.不同卸围压速率下深埋大理岩卸荷力学特性试验研究[J].岩石力学与工程学报,2010,29(9):1807-1817.
[7]李建林,王瑞红,蒋昱州,等.砂岩三轴卸荷力学特性试验研究[J].岩石力学与工程学报,2010,29(10):2034-2041.
[8]郭印同,杨春和,付建军.盐岩三轴卸荷力学特性试验研究[J].岩土力学,2012,33(3):725-730,738.
[9]李成,秦小林,蒋忠信.膨胀岩路堑边坡破坏机理研究[J].铁道工程学报,1995,2(46):51-56.
[10]程展林,李青云,郭熙灵,等.膨胀土边坡稳定性研究[J].长江科学院院报,2011,(10):102-111.
[11]汪明元,徐晗,杨洪,等.非饱和膨胀土边坡破坏机理与稳定性分析[J].南水北调与水利科技,2011,6(1):151-153,158.
[12]陈愈炯.土的卸荷弹性模量[J].工程勘察,1988,(5):6-9.
[2]缪林昌,殷宗泽.非饱和土的剪切强度[J].岩土力学,1999,20(3):1-6.
[3]缪林昌,崔颖.非饱和土的固结与水力特性研究[J].西北地震学报,2011,33(S1):38-42.
[4]徐永福.非饱和膨胀土结构性强度的研究[J].河海大学学报(自然科学版),1999,27(2):89-92.
[5]李建林.卸荷岩体力学[M].北京:中国水利水电出版社,2003.
[6]邱士利,冯夏庭,张传庆,等.不同卸围压速率下深埋大理岩卸荷力学特性试验研究[J].岩石力学与工程学报,2010,29(9):1807-1817.
[7]李建林,王瑞红,蒋昱州,等.砂岩三轴卸荷力学特性试验研究[J].岩石力学与工程学报,2010,29(10):2034-2041.
[8]郭印同,杨春和,付建军.盐岩三轴卸荷力学特性试验研究[J].岩土力学,2012,33(3):725-730,738.
[9]李成,秦小林,蒋忠信.膨胀岩路堑边坡破坏机理研究[J].铁道工程学报,1995,2(46):51-56.
[10]程展林,李青云,郭熙灵,等.膨胀土边坡稳定性研究[J].长江科学院院报,2011,(10):102-111.
[11]汪明元,徐晗,杨洪,等.非饱和膨胀土边坡破坏机理与稳定性分析[J].南水北调与水利科技,2011,6(1):151-153,158.
[12]陈愈炯.土的卸荷弹性模量[J].工程勘察,1988,(5):6-9.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心