冻融作用对海相软土压缩性及抗剪强度影响研究
|
摘要
为揭示原状海相软土冻融前后变形及强度差异性,对宁波原状海相软土及不同冻融条件下的融土进行了压缩实验和三轴固结不排水剪切实验。研究结果表明:单向冻结条件下,冻融作用使海相软土压缩性增强,且对试样不同部位处产生的影响程度不同,对靠近冷端的下部融土压缩性影响最大,中部其次,上部最小;冷端温度越低,冻融作用对融土压缩性影响越小,且逐渐趋于稳定;自然解冻比强制解冻对融土压缩性影响程度更大。冻融作用使融土黏聚力明显减小,内摩擦角略有增大;冷端温度越低,冻融作用对黏聚力和内摩擦角影响程度越大,在一定法向应力范围内,融土破坏强度越小。
In order to reveal the difference in deformation and strength of undisturbed marine soft soils before and after freezing and thawing, compression tests and triaxial consolidation undrained shear tests were performed on the undisturbed Ningbo marine soft soil and the thawing soil under different freezing and thawing conditions. The results show that under the condition of one-way freezing, the freezing and thawing effect enhances the compressibility of the marine soft soil, and the degree of influence on different parts of the sample is different. The compressive property of the lower part near the cold end has the greatest effect, and the middle part has the second and the upper part has the smallest effect. The lower the temperature of the cold end, the smaller the effect of freezing and thawing on the compressibility of the thawing soil, and tends to be stable gradually. Natural thawing has a great influence on compressibility of thawing soil than forced thawing. Freezing and thawing effect obviously decreases the cohesive force of the thawing soil and slightly increases the internal friction angle. The lower the temperature of the cold end, the greater the effect of freezing and thawing on the cohesion and internal friction angle, and the smaller the failure strength of the thawing soil within a certain range of normal stress.
In order to reveal the difference in deformation and strength of undisturbed marine soft soils before and after freezing and thawing, compression tests and triaxial consolidation undrained shear tests were performed on the undisturbed Ningbo marine soft soil and the thawing soil under different freezing and thawing conditions. The results show that under the condition of one-way freezing, the freezing and thawing effect enhances the compressibility of the marine soft soil, and the degree of influence on different parts of the sample is different. The compressive property of the lower part near the cold end has the greatest effect, and the middle part has the second and the upper part has the smallest effect. The lower the temperature of the cold end, the smaller the effect of freezing and thawing on the compressibility of the thawing soil, and tends to be stable gradually. Natural thawing has a great influence on compressibility of thawing soil than forced thawing. Freezing and thawing effect obviously decreases the cohesive force of the thawing soil and slightly increases the internal friction angle. The lower the temperature of the cold end, the greater the effect of freezing and thawing on the cohesion and internal friction angle, and the smaller the failure strength of the thawing soil within a certain range of normal stress.
引文
[1] Yang Ping,Zhang Ting.The physical and the mechanical properties of original and frozen-thawed soil[J].Journal of Glaciology and Geocryology,2002,24(5):665-667.[杨平,张婷.人工冻融土物理力学性能研究[J].冰川冻土,2002,24(5):665-667.]
[2] Chen Sili,Shi Jianjun,Yu Tao,et al.Effects of freezing-thawing cycle of compressibility of cement soil[C]//Applied Mechanics and Materials.Trans Tech Publications,2013,419:837-841.
[3] Shi Huaqiang,Ni Wankui,Liu Kui,et al.The impact of the freezing-thawing cycle to compression of the loess[J].Hydrogeology & Engineering Geology,2012,39(3):45-48.[师华强,倪万魁,刘魁,等.冻融循环作用对黄土压缩性的影响[J].水文地质工程地质,2012,39(3):45-48.]
[4] Yin Qixiang,Zhou Guoqing,Zhao Xiaodong,et al.Experimental study of the water migration and compression of soils under double direction freezing-one direction thawing[J].Rock and Soil Mechanics,2015,36(4) :1021-1026.[阴琪翔,周国庆,赵晓东,等.双向冻结-单向融化土压缩性及水分迁移试验研究[J].岩土力学,2015,36(4):1021-1026.]
[5] Zhang Ying,Bing Hui,Yang Chengsong.Influences of freeze-thaw cycles on mechanical properties of silty clay based on SEM and MIP test[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(Suppl 1):3597-3603.[张英,邴慧,杨成松.基于SEM和MIP的冻融循环对黏土强度影响机制研究[J].岩石力学与岩土工程学报,2015,34(增刊1):3597-3603.]
[6] Wang Dayan,Ma Wei,Chang Xiaoxiao,et al.Physical-mechanical properties changes of Qinghai-Tibet clay due to cyclic freezing and thawing[J].Chinese Journal of Rock Mechanics and Engineering,2005,24 (23):4313-4319.[王大雁,马巍,常小晓,等.冻融循环作用对青藏粘土物理力学性质的影响[J].岩石力学与工程学报,2005,24(23):4313-4319.]
[7] Wang Tianliang,Liu Jiankun,Peng Liyun,et al.Research on the mechanical properties of the cement-modified soil under the action of freezing and thawing cycles[J].China Railway Science,2010,31(6):7-13.[王天亮,刘建坤,彭丽云,等.冻融循环作用下水泥改良土的力学性质研究[J].中国铁道科学,2010,31(6):7-13.]
[8] Jiang Wangyang,Yang Ping,Chen Bin,et al.Experimental study on strength properties of artificial frozen soil in marine soft soil area of Ningbo City,China[J].Journal of Forestry Engineering,2017,2(5):126-131.[江汪洋,杨平,陈斌,等.宁波海相软弱土层人工冻土强度特性试验[J].林业工程学报,2017,2(5):126-131.]
[9] Formanek G E,McCool D K,Papendick R I.Freeze-thaw and consolidation effects on strength of a wet silt loam[J].Transactions of the ASAE,1984,27(6):1749-1752.
[10] Tang Yiqun,Yang Ping,Shen Feng,et al.Microscopic study of dark green silty′s behavior after melted[J].Journal of Tongji University(Natural Science) ,2007,35(1):6-9.[唐益群,杨坪,沈锋,等.上海暗绿色粉质粘土冻融前后微观性状研究[J].同济大学学报(自然科学版),2007,35(1):6-9.]
[11] Wang Xiaobin,Yang Ping,Wang Haibo,et al.Experimental study on effects of freezing and thawing on mechanical properties of clay[J].Chinese Journal of Geotechnical Engineering,2009,31(11):1768-1772.[王效宾,杨平,王海波,等.冻融作用对黏土力学性能影响的试验研究[J].岩土工程学报,2009,31(11):1768-1772.]
[12] Fan Haoming,Qian Duo,Zhou Lili,et al.Effects of freeze-thaw cycle on mechanical properties of black soil[J].Bulletin of Soil and Water Conservation,2011,31(3):81-84.[范昊明,钱多,周丽丽,等.冻融作用对黑土力学性质的影响研究[J].水土保持通报,2011,31(3):81-84.]
[13] Fang Jianhong,Chen Xin,Xu Anhua,et al.Experimental study of the influence of freezing-thawing cycles on physical and mechanical properties of Qinghai-Tibet red clay[J].Journal of Glaciology and Geocryology,2018,40(1):62-69.[房建宏,陈鑫,徐安花,等.冻融循环对青藏红黏土物理力学性质影响试验研究[J].冰川冻土,2018,40(1):62-69.]
[14] Fang Lili,Qi Jilin,Ma Wei.Freeze-thaw induced changes in soil Structure and its relationship with variations in strength[J].Journal of Glaciology and Geocryology,2012,34(2):435-440.[方丽莉,齐吉琳,马巍.冻融作用对土结构性的影响及其导致的强度变化[J].冰川冻土,2012,34(2):435-440.]
[15] Ye Wanjun,Li Changqing,Dong Xihao,et al.Study on damage identification of loess microstructure and macro mechanical response under freezing and thawing conditions[J].Journal of Glaciology and Geocryology,2018,40(3):546-555.[叶万军,李长清,董西好,等.冻融环境下黄土微结构损伤识别与宏观力学响应规律研究[J].冰川冻土,2018,40(3):546-555.]
[16] Harris J S.Ground Freezing in Practice[M].London:Thomas Telford Publishing,1995.
[17] Yong R N,Boonsinsuk P.Alteration of soil behavior after cyclic freezing and thawing[C]// Proc of Fourth International Symposium on Ground Freezing,Sapporo,1985.
[18] Li Y.Effects of particle shape and size distribution on the shear strength behavior of composite soils[J].Bulletin of Engineering Geology and the Environment,2013,72(3/4):371-381.
[2] Chen Sili,Shi Jianjun,Yu Tao,et al.Effects of freezing-thawing cycle of compressibility of cement soil[C]//Applied Mechanics and Materials.Trans Tech Publications,2013,419:837-841.
[3] Shi Huaqiang,Ni Wankui,Liu Kui,et al.The impact of the freezing-thawing cycle to compression of the loess[J].Hydrogeology & Engineering Geology,2012,39(3):45-48.[师华强,倪万魁,刘魁,等.冻融循环作用对黄土压缩性的影响[J].水文地质工程地质,2012,39(3):45-48.]
[4] Yin Qixiang,Zhou Guoqing,Zhao Xiaodong,et al.Experimental study of the water migration and compression of soils under double direction freezing-one direction thawing[J].Rock and Soil Mechanics,2015,36(4) :1021-1026.[阴琪翔,周国庆,赵晓东,等.双向冻结-单向融化土压缩性及水分迁移试验研究[J].岩土力学,2015,36(4):1021-1026.]
[5] Zhang Ying,Bing Hui,Yang Chengsong.Influences of freeze-thaw cycles on mechanical properties of silty clay based on SEM and MIP test[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(Suppl 1):3597-3603.[张英,邴慧,杨成松.基于SEM和MIP的冻融循环对黏土强度影响机制研究[J].岩石力学与岩土工程学报,2015,34(增刊1):3597-3603.]
[6] Wang Dayan,Ma Wei,Chang Xiaoxiao,et al.Physical-mechanical properties changes of Qinghai-Tibet clay due to cyclic freezing and thawing[J].Chinese Journal of Rock Mechanics and Engineering,2005,24 (23):4313-4319.[王大雁,马巍,常小晓,等.冻融循环作用对青藏粘土物理力学性质的影响[J].岩石力学与工程学报,2005,24(23):4313-4319.]
[7] Wang Tianliang,Liu Jiankun,Peng Liyun,et al.Research on the mechanical properties of the cement-modified soil under the action of freezing and thawing cycles[J].China Railway Science,2010,31(6):7-13.[王天亮,刘建坤,彭丽云,等.冻融循环作用下水泥改良土的力学性质研究[J].中国铁道科学,2010,31(6):7-13.]
[8] Jiang Wangyang,Yang Ping,Chen Bin,et al.Experimental study on strength properties of artificial frozen soil in marine soft soil area of Ningbo City,China[J].Journal of Forestry Engineering,2017,2(5):126-131.[江汪洋,杨平,陈斌,等.宁波海相软弱土层人工冻土强度特性试验[J].林业工程学报,2017,2(5):126-131.]
[9] Formanek G E,McCool D K,Papendick R I.Freeze-thaw and consolidation effects on strength of a wet silt loam[J].Transactions of the ASAE,1984,27(6):1749-1752.
[10] Tang Yiqun,Yang Ping,Shen Feng,et al.Microscopic study of dark green silty′s behavior after melted[J].Journal of Tongji University(Natural Science) ,2007,35(1):6-9.[唐益群,杨坪,沈锋,等.上海暗绿色粉质粘土冻融前后微观性状研究[J].同济大学学报(自然科学版),2007,35(1):6-9.]
[11] Wang Xiaobin,Yang Ping,Wang Haibo,et al.Experimental study on effects of freezing and thawing on mechanical properties of clay[J].Chinese Journal of Geotechnical Engineering,2009,31(11):1768-1772.[王效宾,杨平,王海波,等.冻融作用对黏土力学性能影响的试验研究[J].岩土工程学报,2009,31(11):1768-1772.]
[12] Fan Haoming,Qian Duo,Zhou Lili,et al.Effects of freeze-thaw cycle on mechanical properties of black soil[J].Bulletin of Soil and Water Conservation,2011,31(3):81-84.[范昊明,钱多,周丽丽,等.冻融作用对黑土力学性质的影响研究[J].水土保持通报,2011,31(3):81-84.]
[13] Fang Jianhong,Chen Xin,Xu Anhua,et al.Experimental study of the influence of freezing-thawing cycles on physical and mechanical properties of Qinghai-Tibet red clay[J].Journal of Glaciology and Geocryology,2018,40(1):62-69.[房建宏,陈鑫,徐安花,等.冻融循环对青藏红黏土物理力学性质影响试验研究[J].冰川冻土,2018,40(1):62-69.]
[14] Fang Lili,Qi Jilin,Ma Wei.Freeze-thaw induced changes in soil Structure and its relationship with variations in strength[J].Journal of Glaciology and Geocryology,2012,34(2):435-440.[方丽莉,齐吉琳,马巍.冻融作用对土结构性的影响及其导致的强度变化[J].冰川冻土,2012,34(2):435-440.]
[15] Ye Wanjun,Li Changqing,Dong Xihao,et al.Study on damage identification of loess microstructure and macro mechanical response under freezing and thawing conditions[J].Journal of Glaciology and Geocryology,2018,40(3):546-555.[叶万军,李长清,董西好,等.冻融环境下黄土微结构损伤识别与宏观力学响应规律研究[J].冰川冻土,2018,40(3):546-555.]
[16] Harris J S.Ground Freezing in Practice[M].London:Thomas Telford Publishing,1995.
[17] Yong R N,Boonsinsuk P.Alteration of soil behavior after cyclic freezing and thawing[C]// Proc of Fourth International Symposium on Ground Freezing,Sapporo,1985.
[18] Li Y.Effects of particle shape and size distribution on the shear strength behavior of composite soils[J].Bulletin of Engineering Geology and the Environment,2013,72(3/4):371-381.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |