饱和砂土液化过程中细观组构的模型试验研究
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摘要
采用室内振动台模型试验对液化过程中饱和砂土颗粒的细观组构进行研究.分析了砂土颗粒在液化破坏过程中颗粒长轴方向、平均配位数、孔隙率的演化规律及其与宏观现象之间的联系.应用表征上述量的组构参数分析了砂土的诱发各向异性,指出在循环荷载的作用下,砂土颗粒不断重新排列定向以适应新的应力状态,导致累积配位数的丧失、孔隙率增大,继而导致液化的发生.研究成果对于揭示砂土变形(液化)的细观机理以及建立砂土的细观力学模型都具有重要意义.
Based on the shaking table model testing,the mesofabric characteristics of saturated sand are studied including macro-axis orientation for sand granules,average coordination numbers and porosity.Induced anisotropy of sand is analyzed by fabric features.The results show that under cyclic loading, sand granules continuously rearrange and redirect for the new stress state which results in decreasing cumulative coordination numbers and increasing porosity,and then liquefaction.The study is expected to contribute to disclosing the meso-mechanism of sand liquefaction relating to the mesofabric and macro mechanical response of granular soils and developing meso-mechanical models of granular media.
Based on the shaking table model testing,the mesofabric characteristics of saturated sand are studied including macro-axis orientation for sand granules,average coordination numbers and porosity.Induced anisotropy of sand is analyzed by fabric features.The results show that under cyclic loading, sand granules continuously rearrange and redirect for the new stress state which results in decreasing cumulative coordination numbers and increasing porosity,and then liquefaction.The study is expected to contribute to disclosing the meso-mechanism of sand liquefaction relating to the mesofabric and macro mechanical response of granular soils and developing meso-mechanical models of granular media.
引文
[1]沈珠江.现代土力学的基本问题[J].力学与实践,1998,20 (6):1. SHEN Zhujiang.Foundamental problems in the modern soil mechanics[J].Mechanics and Engineering,1998,20(6):1.
[2]刘汉龙.余湘娟.土动力学与岩土地震工程研究进展[J].河海大学学报,1999,27(1):6. LIU Hanlong,YU Xiangjuan.Advance in soil dynamics and geotechnical earthquake engineering[J].Journal of Hohai University,1999,27(1):6.
[3]李亮,赵成刚.饱和土体动力本构模型研究进展[J].世界地震工程,2004,20(1):138. LI Liang,ZHAO Chenggang.Advances on the research of dynamic constitutive models of saturated soils[J].World Information on Earthquake Engineering,2004,20(1):138.
[4]史旦达.单调与循环加荷条件下砂土力学性质细观模拟[D].上海:同济大学土木工程学院,2007. SHI Danda.Micromechanical simulations of sand behavior under monotonic and cyclic loading[D].Shanghai:Tongji University. School of Civil Engineering,2007.
[5]Oda M.Initial fabrics and their relations to mechanical properties of granular materials[J].Soils and Foundations, 1972,12(1):17.
[6]Oda M,Konishi J.Microscopic deformation mechanism of granular materials[J].Soils and Foundations,1974,14(4):25.
[7]Oda M,Nemat-Nasser S,Mehrabadi M M.A statistical study of fabric in a random assembly of spherical granules[J]. International Journal for Numerical and Analytical Methods in Geomechanics,1982,6:77.
[8]Oda M,Takahashi M,Takahashi M.Microstructure in shear band observed by microfocus X-ray computed tomography[J]. Geotechnique,2004,54(8):539.
[9]沈珠江.砂土液化分析的散粒体模型[J].岩土工程学报, 1999,21(6):742. SHEN Zhujiang.A granular medium model for liquefaction analysis of sands[J].Chinese Journal of Geotechnical Engineering,1999,21(6):742.
[10]Satake M.Constitution of mechanics of granular materials through graph representation[J].Theoretical and Applied Mechanics,1978,26:257.
[11]Nemat-Nasser S.Influence of fabric on liquefaction and densification potential of cohesionless sand[J].Mechanics of Materials,1982,1(1):43.
[12]Horne M R.The behaviour of an assembly of rotund,rigid, cohesionless particles[J].Mathematical and Physical Sciences, 1965,286(1404):62.
[13]沈珠江.复杂荷载下砂土液化变形的结构性模型[C]//第五届全国土动力学学术会议论文集.大连:大连理工大学出版社, 1998:1-10. SHEN Zhujiang.Structured model of liquefaction-induced deformation in sand under complex loading[C]//Proceeding of the 5th National Conference on Soil Dynamics.Dalian:Dalian University of Technology Press,1998:1-10.
[14]李元海.数字照相变形量测技术及其在岩土模型试验中的应用研究[D].上海:同济大学土木工程学院,2003. LI Yuanhai.Study on digital photography-based deformation measurement technique and its application in geo-physical model experiment[D].Shanghai:Tongji University.School of Civil Engineering,2003.
[15]周健,余荣传,贾敏才.基于数字图像技术的砂土模型试验细观结构参数量测[J].岩土工程学报,2006,28(12):2047. ZHOU Jian,YU Rongchuan,JIA Mincai.Measurement ot microstructure parameters for granular soil model using digital image technology[J].Chinese Journal of Geotechnical Engineering,2006,28(12):2047.
[2]刘汉龙.余湘娟.土动力学与岩土地震工程研究进展[J].河海大学学报,1999,27(1):6. LIU Hanlong,YU Xiangjuan.Advance in soil dynamics and geotechnical earthquake engineering[J].Journal of Hohai University,1999,27(1):6.
[3]李亮,赵成刚.饱和土体动力本构模型研究进展[J].世界地震工程,2004,20(1):138. LI Liang,ZHAO Chenggang.Advances on the research of dynamic constitutive models of saturated soils[J].World Information on Earthquake Engineering,2004,20(1):138.
[4]史旦达.单调与循环加荷条件下砂土力学性质细观模拟[D].上海:同济大学土木工程学院,2007. SHI Danda.Micromechanical simulations of sand behavior under monotonic and cyclic loading[D].Shanghai:Tongji University. School of Civil Engineering,2007.
[5]Oda M.Initial fabrics and their relations to mechanical properties of granular materials[J].Soils and Foundations, 1972,12(1):17.
[6]Oda M,Konishi J.Microscopic deformation mechanism of granular materials[J].Soils and Foundations,1974,14(4):25.
[7]Oda M,Nemat-Nasser S,Mehrabadi M M.A statistical study of fabric in a random assembly of spherical granules[J]. International Journal for Numerical and Analytical Methods in Geomechanics,1982,6:77.
[8]Oda M,Takahashi M,Takahashi M.Microstructure in shear band observed by microfocus X-ray computed tomography[J]. Geotechnique,2004,54(8):539.
[9]沈珠江.砂土液化分析的散粒体模型[J].岩土工程学报, 1999,21(6):742. SHEN Zhujiang.A granular medium model for liquefaction analysis of sands[J].Chinese Journal of Geotechnical Engineering,1999,21(6):742.
[10]Satake M.Constitution of mechanics of granular materials through graph representation[J].Theoretical and Applied Mechanics,1978,26:257.
[11]Nemat-Nasser S.Influence of fabric on liquefaction and densification potential of cohesionless sand[J].Mechanics of Materials,1982,1(1):43.
[12]Horne M R.The behaviour of an assembly of rotund,rigid, cohesionless particles[J].Mathematical and Physical Sciences, 1965,286(1404):62.
[13]沈珠江.复杂荷载下砂土液化变形的结构性模型[C]//第五届全国土动力学学术会议论文集.大连:大连理工大学出版社, 1998:1-10. SHEN Zhujiang.Structured model of liquefaction-induced deformation in sand under complex loading[C]//Proceeding of the 5th National Conference on Soil Dynamics.Dalian:Dalian University of Technology Press,1998:1-10.
[14]李元海.数字照相变形量测技术及其在岩土模型试验中的应用研究[D].上海:同济大学土木工程学院,2003. LI Yuanhai.Study on digital photography-based deformation measurement technique and its application in geo-physical model experiment[D].Shanghai:Tongji University.School of Civil Engineering,2003.
[15]周健,余荣传,贾敏才.基于数字图像技术的砂土模型试验细观结构参数量测[J].岩土工程学报,2006,28(12):2047. ZHOU Jian,YU Rongchuan,JIA Mincai.Measurement ot microstructure parameters for granular soil model using digital image technology[J].Chinese Journal of Geotechnical Engineering,2006,28(12):2047.
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