饱和重塑黄土动力特性及残余变形规律研究
|
摘要
在不同固结条件下对饱和重塑黄土进行动三轴试验,探讨了饱和重塑黄土在固结排水下的动应力应变、体变、残余应变特性,以及固结不排水条件下的动孔压、有效应力路径等特性。并基于三轴试验结果,修正了残余剪应变增量、残余体积应变增量的经验公式。试验结果表明:排水条件下,动应力、围压和固结应力比变化对饱和重塑黄土的体变曲线形态和体变值有较大影响。在均压固结和偏压固结条件下饱和重塑黄土均产生较大的残余应变,围压、动应力变化对残余应变增长曲线基本上无影响。残余剪应变比增长曲线在均压固结和偏压固结时具有相同的形态,都可以用指数函数来描述;而残余体变比-振次比关系在均压固结时呈线性分布,而偏压固结时呈指数型分布。不排水条件下,随着固结应力比的增大,孔压增长曲线由明显上凸型向微凸型转变,孔压比的增长速率也随着围压的增大而减小。
Based on dynamic triaxial tests conducted on saturated remolded loess under different consolidation conditions,the characteristics of dynamic stress-strain,volume strain,residual strain under consolidated-drained conditions and dynamic pore water pressure,effective stress path under consolidated-undrained condition are studied.Then based on the test results,the empirical formula of residual shear strain increment,residual volume strain increment were modified. It is indicated that: under drained conditions,the curve shape and value of volume strain is affected greatly by the dynamic stress,variation of confining pressure and consolidation stress ratio. The great residual strain can be resulted under both isotropic consolidation and anisotropic consolidation,but the relationships between residual strain and number of cycles are hardly affected by the variation of confining pressure and dynamic stress. The curve shape of residual shear strain ratio under isotropic consolidation is the same as that under anisotropic consolidation,and the relationship between residual shear strain ratio and cycle times ratio could be described by exponential function. The relationship between residual volume strain ratio and cycle number ratio could be described by linear function under isotropic consolidations and by exponential function under anisotropic consolidations. Under undrained conditions,the shape of pore water pressure developing curve changes from obvious-convex to micro-convex as long as the consolidation ratio increases,and the growth of pore water pressure ratio decreases with the increasing confining pressure.
Based on dynamic triaxial tests conducted on saturated remolded loess under different consolidation conditions,the characteristics of dynamic stress-strain,volume strain,residual strain under consolidated-drained conditions and dynamic pore water pressure,effective stress path under consolidated-undrained condition are studied.Then based on the test results,the empirical formula of residual shear strain increment,residual volume strain increment were modified. It is indicated that: under drained conditions,the curve shape and value of volume strain is affected greatly by the dynamic stress,variation of confining pressure and consolidation stress ratio. The great residual strain can be resulted under both isotropic consolidation and anisotropic consolidation,but the relationships between residual strain and number of cycles are hardly affected by the variation of confining pressure and dynamic stress. The curve shape of residual shear strain ratio under isotropic consolidation is the same as that under anisotropic consolidation,and the relationship between residual shear strain ratio and cycle times ratio could be described by exponential function. The relationship between residual volume strain ratio and cycle number ratio could be described by linear function under isotropic consolidations and by exponential function under anisotropic consolidations. Under undrained conditions,the shape of pore water pressure developing curve changes from obvious-convex to micro-convex as long as the consolidation ratio increases,and the growth of pore water pressure ratio decreases with the increasing confining pressure.
引文
[1]曹鹏,魏巍,刘恩龙,等.饱和重塑黄土的动力特性[J].南水北调与水利科技,2016,14(2):136-141.CAO Peng,WEI Wei,LIU Enlong,et al. Dynamic properties of saturated remolded loess[J]. South-to-North Water Transfer and Water Science&Technology,2016,14(2):136-141.(in Chinese)
[2]李铮,李宏恩,范光亚.饱和黄土静、动力特性试验研究[J].防灾减灾工程学报,2013,33(增刊1):111-116.LI Zheng,LI Hongen,FAN Guangya. Experimental study on static and dynamic properties of saturated loess[J]. Journal of Disaster Prevention and Mitigation Engineering,2013,33(S1):111-116.(in Chinese)
[3]陈存礼,杨鹏,何军芳.饱和击实黄土的动力特性研究[J].岩土力学,2007,28(8):1551-1556.CHEN Cunli,YANG Peng,HE Junfang. Research on dynamic characteristics of saturated compacted loess[J]. Rock and Soil Mechanics,2007,28(8):1551-1556.(in Chinese)
[4]谷天峰,王家鼎,刘亚明.循环荷载下压实黄土动强度特性研究[J].工程地质学报,2015,23(4):604-608.GU Tianfeng,WANG Jiading,LIU Yaming. Dynamic strength characteristics of compacted loess under cyclic loads[J]. Journal of Engineering Geology,2015,23(4):604-608.(in Chinese)
[5]李焱,骆亚生,谭东岳,等.振动频率对压实黄土动强度特性的影响[J].水土保持通报,2009,29(4):130-133.LI Yan,LUO Yasheng,TAN Dongyue,et al. Effects of vibration frequency on dynamic strength properties of compacted loess[J]. Bulletin of Soil and Water Conservation,29(4):130-133.(in Chinese)
[6]刘建民,周云东,张立志,等.饱和重塑黄土液化应变发展试验研究[J].江西理工大学学报,2012,33(1):39-43.LIU Jianmin,ZHOU Yundong,ZHANG Lizhi,et al. Experimental study of strain development on saturated remolded loess liquefaction[J]. Journal of Jiangxi University of Science and Technology,2012,33(1):39-43.(in Chinese)
[7]张军,郑俊杰,曹文昭,等.循环荷载作用下饱和压实黄土动力特性研究[J].岩土工程学报,2013,35(增刊1):322-327.ZHANG Jun,ZHENG Junjie,CAO Wenzhao,et al. Dynamic characteristics of saturated compacted loess under cyclic loads[J]. Chinese Journal of Geotechnical Engineering,2013,35(S1):322-327.(in Chinese)
[8]刘保健,张晓荣,程海涛.应变控制下压实黄土的动三轴试验研究[J].岩土力学,2007,28(6):1073-1076.LIU Baojian,ZHANG Xiaorong,CHENG Haitao. Study on compacted loess under strain control at dynamic triaxial test[J]. Rock and Soil Mechanics,2007,28(6):1073-1076.(in Chinese)
[9]雷华阳,姜岩,陆培毅,等.交通荷载作用下结构性软土动应力-动应变关系试验研究[J].岩石力学与工程学报,2008,27(增刊1):3052-3057.LEI Huayang,JIANG Yan,LU Peiyi,et al. Experimental study of dynamic stress-strain relation of structural soft soil under traffic load[J]. Chinese Journal of Rock Mechanics and Engineering,2008,27(S1):3052-3057.(in Chinese)
[10]李华明,蒋关鲁,吴丽君,等.黄土地基动力沉降特性试验研究[J].岩土力学,2009,30(8):2220-2224.LI Huaming,JIANG Guanlu,WU Lijun,et al. Experimental study of dynamic settlement behavior of loess foundation[J]. Rock and Soil Mechanics,2009,30(8):2220-2224.(in Chinese)
[11]廖红建,肖正华,刘健.动载下饱和重塑黄土的骨干曲线变化研究[J].岩土力学,2011,32(2):375-379.LIAO Hongjian,XIAO Zhenghua,LIU Jian. Study of variation of backbone curve of saturated remolded loess under dynamic loading[J]. Rock and Soil Mechanics,2011,32(2):375-379.(in Chinese)
[12]邓龙胜,范文,贺龙鹏.随机地震荷载作用下黄土的液化特性[J].岩石力学与工程学报,2012,31(6):1274-1280.DENG Longsheng,FAN Wen,HE Longpeng. Liquefaction property of loess stochastic seismic load[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(6):1274-1280.(in Chinese)
[13] Gu C,Wang J,Cai Y,et al. Undrained cyclic triaxial behavior of saturated clays under variable confining pressure[J]. Soil Dynamics&Earthquake Engineering,2012,40(3):118-128.
[14]廖红建,宋丽,杨政,等.往返荷载下粘性土的强度及取值标准试验研究[J].岩土力学,2001,22(1):16-20.LIAO Hongjian,SONG Li,YANG Zheng,et al. Experiment study on shear strength and yield criterion of cohesive soils under repeated loads[J]. Rock and Soil Mechanics,2001,22(1):16-20.(in Chinese)
[15]王志杰,骆亚生,谭东岳,等.干密度对预剪应力下重塑黄土动力特性影响的试验研究[J].地震工程学报,2011,33(4):349-353.WANG Zhijie,LUO Yasheng,TAN Dongyue,et al. Experimental study on the effects of dry density on dynamic properties of remodeled loess under condition of pre-shearing stress[J]. China Earthquake Engineering Journal,2011,33(4):349-353.(in Chinese)
[16]王峻,李兰.俄罗斯伊尔库茨克地区黄土动力特性实验研究[J].地震工程学报,2001,23(3):71-75.WANG Jun,LI Lan. The laboratory study on dynamic characteristics Loess in Irkutsk,Russia[J]. China Earthquake Engineering Journal,2001,23(3):71-75.(in Chinese)
[17]谢定义.土动力学[M].北京:高等教育出版社,2011:102-105.XIE Dingyi. Soil Dynamics[M]. Beijing:Higher Education Press,2011:102-105.(in Chinese)
[18] SL 237—1999土工试验规程[S].北京:中华人民共和国水利部,1999.SL 237—1999 Specification of Soil Test[S]. Beijing:The Ministry of Water Resources of the People's Republic of China,1999.(in Chinese)
[19]汪闻韶.土的动力强度和液化特性[M].北京:中国电力出版社,1997.WANG Wenshao. Dynamic Strength and Liquefaction Characteristics of Soil[M]. Beijing:China Electric Power Press,1997.(in Chinese)
[20]汪闻韶.土的液化机理[J].水利学报,1981(5):24-36.WANG Wenshao. Liquefaction mechanism of soil[J]. Journal of Hydraulic Engineering,1981(5):24-36.(in Chinese)
[21]沈珠江.饱和砂土的动力渗流变形计算[J].水利学报,1980(2):16-24.SHEN Zhujiang. Dynamic seepage deformation calculation of saturated sand[J]. Journal of Hydraulic Engineering,1980(2):16-24.(in Chinese)
[22]沈珠江.砂土动力液化变形的有效应力分析方法[J].水利水运工程学报,1982(4):25-35.SHEN Zhujiang. Effective stress method in dynamic liquefaction of sand[J]. Journal of Hydro-Science and Engineering,1982(4):25-35.(in Chinese)
[2]李铮,李宏恩,范光亚.饱和黄土静、动力特性试验研究[J].防灾减灾工程学报,2013,33(增刊1):111-116.LI Zheng,LI Hongen,FAN Guangya. Experimental study on static and dynamic properties of saturated loess[J]. Journal of Disaster Prevention and Mitigation Engineering,2013,33(S1):111-116.(in Chinese)
[3]陈存礼,杨鹏,何军芳.饱和击实黄土的动力特性研究[J].岩土力学,2007,28(8):1551-1556.CHEN Cunli,YANG Peng,HE Junfang. Research on dynamic characteristics of saturated compacted loess[J]. Rock and Soil Mechanics,2007,28(8):1551-1556.(in Chinese)
[4]谷天峰,王家鼎,刘亚明.循环荷载下压实黄土动强度特性研究[J].工程地质学报,2015,23(4):604-608.GU Tianfeng,WANG Jiading,LIU Yaming. Dynamic strength characteristics of compacted loess under cyclic loads[J]. Journal of Engineering Geology,2015,23(4):604-608.(in Chinese)
[5]李焱,骆亚生,谭东岳,等.振动频率对压实黄土动强度特性的影响[J].水土保持通报,2009,29(4):130-133.LI Yan,LUO Yasheng,TAN Dongyue,et al. Effects of vibration frequency on dynamic strength properties of compacted loess[J]. Bulletin of Soil and Water Conservation,29(4):130-133.(in Chinese)
[6]刘建民,周云东,张立志,等.饱和重塑黄土液化应变发展试验研究[J].江西理工大学学报,2012,33(1):39-43.LIU Jianmin,ZHOU Yundong,ZHANG Lizhi,et al. Experimental study of strain development on saturated remolded loess liquefaction[J]. Journal of Jiangxi University of Science and Technology,2012,33(1):39-43.(in Chinese)
[7]张军,郑俊杰,曹文昭,等.循环荷载作用下饱和压实黄土动力特性研究[J].岩土工程学报,2013,35(增刊1):322-327.ZHANG Jun,ZHENG Junjie,CAO Wenzhao,et al. Dynamic characteristics of saturated compacted loess under cyclic loads[J]. Chinese Journal of Geotechnical Engineering,2013,35(S1):322-327.(in Chinese)
[8]刘保健,张晓荣,程海涛.应变控制下压实黄土的动三轴试验研究[J].岩土力学,2007,28(6):1073-1076.LIU Baojian,ZHANG Xiaorong,CHENG Haitao. Study on compacted loess under strain control at dynamic triaxial test[J]. Rock and Soil Mechanics,2007,28(6):1073-1076.(in Chinese)
[9]雷华阳,姜岩,陆培毅,等.交通荷载作用下结构性软土动应力-动应变关系试验研究[J].岩石力学与工程学报,2008,27(增刊1):3052-3057.LEI Huayang,JIANG Yan,LU Peiyi,et al. Experimental study of dynamic stress-strain relation of structural soft soil under traffic load[J]. Chinese Journal of Rock Mechanics and Engineering,2008,27(S1):3052-3057.(in Chinese)
[10]李华明,蒋关鲁,吴丽君,等.黄土地基动力沉降特性试验研究[J].岩土力学,2009,30(8):2220-2224.LI Huaming,JIANG Guanlu,WU Lijun,et al. Experimental study of dynamic settlement behavior of loess foundation[J]. Rock and Soil Mechanics,2009,30(8):2220-2224.(in Chinese)
[11]廖红建,肖正华,刘健.动载下饱和重塑黄土的骨干曲线变化研究[J].岩土力学,2011,32(2):375-379.LIAO Hongjian,XIAO Zhenghua,LIU Jian. Study of variation of backbone curve of saturated remolded loess under dynamic loading[J]. Rock and Soil Mechanics,2011,32(2):375-379.(in Chinese)
[12]邓龙胜,范文,贺龙鹏.随机地震荷载作用下黄土的液化特性[J].岩石力学与工程学报,2012,31(6):1274-1280.DENG Longsheng,FAN Wen,HE Longpeng. Liquefaction property of loess stochastic seismic load[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(6):1274-1280.(in Chinese)
[13] Gu C,Wang J,Cai Y,et al. Undrained cyclic triaxial behavior of saturated clays under variable confining pressure[J]. Soil Dynamics&Earthquake Engineering,2012,40(3):118-128.
[14]廖红建,宋丽,杨政,等.往返荷载下粘性土的强度及取值标准试验研究[J].岩土力学,2001,22(1):16-20.LIAO Hongjian,SONG Li,YANG Zheng,et al. Experiment study on shear strength and yield criterion of cohesive soils under repeated loads[J]. Rock and Soil Mechanics,2001,22(1):16-20.(in Chinese)
[15]王志杰,骆亚生,谭东岳,等.干密度对预剪应力下重塑黄土动力特性影响的试验研究[J].地震工程学报,2011,33(4):349-353.WANG Zhijie,LUO Yasheng,TAN Dongyue,et al. Experimental study on the effects of dry density on dynamic properties of remodeled loess under condition of pre-shearing stress[J]. China Earthquake Engineering Journal,2011,33(4):349-353.(in Chinese)
[16]王峻,李兰.俄罗斯伊尔库茨克地区黄土动力特性实验研究[J].地震工程学报,2001,23(3):71-75.WANG Jun,LI Lan. The laboratory study on dynamic characteristics Loess in Irkutsk,Russia[J]. China Earthquake Engineering Journal,2001,23(3):71-75.(in Chinese)
[17]谢定义.土动力学[M].北京:高等教育出版社,2011:102-105.XIE Dingyi. Soil Dynamics[M]. Beijing:Higher Education Press,2011:102-105.(in Chinese)
[18] SL 237—1999土工试验规程[S].北京:中华人民共和国水利部,1999.SL 237—1999 Specification of Soil Test[S]. Beijing:The Ministry of Water Resources of the People's Republic of China,1999.(in Chinese)
[19]汪闻韶.土的动力强度和液化特性[M].北京:中国电力出版社,1997.WANG Wenshao. Dynamic Strength and Liquefaction Characteristics of Soil[M]. Beijing:China Electric Power Press,1997.(in Chinese)
[20]汪闻韶.土的液化机理[J].水利学报,1981(5):24-36.WANG Wenshao. Liquefaction mechanism of soil[J]. Journal of Hydraulic Engineering,1981(5):24-36.(in Chinese)
[21]沈珠江.饱和砂土的动力渗流变形计算[J].水利学报,1980(2):16-24.SHEN Zhujiang. Dynamic seepage deformation calculation of saturated sand[J]. Journal of Hydraulic Engineering,1980(2):16-24.(in Chinese)
[22]沈珠江.砂土动力液化变形的有效应力分析方法[J].水利水运工程学报,1982(4):25-35.SHEN Zhujiang. Effective stress method in dynamic liquefaction of sand[J]. Journal of Hydro-Science and Engineering,1982(4):25-35.(in Chinese)