杭州第四系软土动力特性试验与土结构性影响的探讨
|
摘要
受新构造运动和气候变化的影响,杭州第四系软土地层相变多而复杂,并具有一定的结构性。为了研究杭州市第四系结构性软土的动力特性,开展了一系列动三轴试验,从而得到工程场地土的动应力-应变骨干曲线以及相关动力特性参数。通过试验研究发现,地层沉积环境的变化使软黏土产生结构性,并对其初始动弹性模量Ed0产生较大的影响。但土的结构性对于最大动应变幅值的控制是随机的,影响并不明显。结构性软土层的剪切波速值与测试点深度之间基本呈幂函数的关系形式,但土结构性特点会使剪切波速与深度的统计关系图象出现分叉。此外,土的结构性对阻尼比与剪切模量的统计关系方程会有一定的影响。
Due to new tectonics movements and drastic climate change,there are different types,and thicknesses of sediment on Quaternary soft clay in Hangzhou region,which have some characteristics of structural properties in particular.In order to investigate the dynamic characteristics of Quaternary soft clay in Hangzhou region,a series of dynamic triaxial tests are conducted.The stress-strain backbone curves and some kinds of dynamic property parameters of structured soft clay in Hangzhou are obtained.It is discovered that the change of the sediment environment is a cause to structural properties of soft clay in Hangzhou region and affects initial dynamic elastic modulus Ed0 obviously.On the side of the maximum amplitude on dynamic strain,the control of structural properties of soft clay is random and unobvious.Generally,there is a good power function relationship between the shear wave velocity and buried depth of structural soft clay,but the different kinds of structural soft clays may have different relationships.In addition,it is shown that structural properties of soft clay could have some influences on the relationship between damping ratio and shear modulus.
Due to new tectonics movements and drastic climate change,there are different types,and thicknesses of sediment on Quaternary soft clay in Hangzhou region,which have some characteristics of structural properties in particular.In order to investigate the dynamic characteristics of Quaternary soft clay in Hangzhou region,a series of dynamic triaxial tests are conducted.The stress-strain backbone curves and some kinds of dynamic property parameters of structured soft clay in Hangzhou are obtained.It is discovered that the change of the sediment environment is a cause to structural properties of soft clay in Hangzhou region and affects initial dynamic elastic modulus Ed0 obviously.On the side of the maximum amplitude on dynamic strain,the control of structural properties of soft clay is random and unobvious.Generally,there is a good power function relationship between the shear wave velocity and buried depth of structural soft clay,but the different kinds of structural soft clays may have different relationships.In addition,it is shown that structural properties of soft clay could have some influences on the relationship between damping ratio and shear modulus.
引文
[1]谭罗荣,孔令伟.特殊岩土工程土质学[M].北京:科学出版社,2006.
[2]张勇,孔令伟,李雄威.循环荷载下饱和软黏土的动骨干曲线模型研究[J].岩土力学,2010,31(6):1699-1704,1708.ZHANG Yong,KONG Ling-wei,LI Xiong-wei.Dynamicbackbone curve model of saturated soft clay under cyclicloading[J].Rock and Soil Mechanics,2010,31(6):1699-1704,1708.
[3]HARDIN B O,DRNEVICH V P.Shear modulus anddamping in soil measurement and parameter effect[J].Journal of the Soil Mechanics and FoundationEngineering Division,1972,98(6):603-624.
[4]RAMBERG W,OSGOOD W R.Description of stressstrain curves by three parameters[R].Washington D C:National Advisory Committee for Aeronautics,TechnicalNote 902,1943.
[5]FINN W D,LEE K L,MARTIN G R.An effective stressmodel for liquefaction[J].Journal of GeotechnicalEngineering,ASCE,1977,(6):517-533.
[6]PYKE R M.Nonlinear soil models for irregular cyclicloading[J].Journal of Geotechnical Engineering,ASCE,1979,(6):715-726.
[7]GB/T50269-97地基动力特性测试规范[S].
[8]孙静.岩土动剪切模量阻尼比试验及应用研究[D].哈尔滨:中国地震局工程力学研究所,2004.
[9]CHEN Guo-xing,LIU Xue-zhu.The preliminary study ondynamic characteristics of recently deposited soils insouthern area of Jiangsu province,China[C]//Proceedingsof the International Symposium on Innovation andSustainability of Structures in Civil Engineering.Nanjing:[s.n.],2005:1332-1339.
[10]KOKUSHO T,YOSHIDA Y,ESAHI Y.Dynamicproperties of soft clays for wide strain range[J].Soils andFoundations,1982,(4):1-18.
[2]张勇,孔令伟,李雄威.循环荷载下饱和软黏土的动骨干曲线模型研究[J].岩土力学,2010,31(6):1699-1704,1708.ZHANG Yong,KONG Ling-wei,LI Xiong-wei.Dynamicbackbone curve model of saturated soft clay under cyclicloading[J].Rock and Soil Mechanics,2010,31(6):1699-1704,1708.
[3]HARDIN B O,DRNEVICH V P.Shear modulus anddamping in soil measurement and parameter effect[J].Journal of the Soil Mechanics and FoundationEngineering Division,1972,98(6):603-624.
[4]RAMBERG W,OSGOOD W R.Description of stressstrain curves by three parameters[R].Washington D C:National Advisory Committee for Aeronautics,TechnicalNote 902,1943.
[5]FINN W D,LEE K L,MARTIN G R.An effective stressmodel for liquefaction[J].Journal of GeotechnicalEngineering,ASCE,1977,(6):517-533.
[6]PYKE R M.Nonlinear soil models for irregular cyclicloading[J].Journal of Geotechnical Engineering,ASCE,1979,(6):715-726.
[7]GB/T50269-97地基动力特性测试规范[S].
[8]孙静.岩土动剪切模量阻尼比试验及应用研究[D].哈尔滨:中国地震局工程力学研究所,2004.
[9]CHEN Guo-xing,LIU Xue-zhu.The preliminary study ondynamic characteristics of recently deposited soils insouthern area of Jiangsu province,China[C]//Proceedingsof the International Symposium on Innovation andSustainability of Structures in Civil Engineering.Nanjing:[s.n.],2005:1332-1339.
[10]KOKUSHO T,YOSHIDA Y,ESAHI Y.Dynamicproperties of soft clays for wide strain range[J].Soils andFoundations,1982,(4):1-18.
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