无黏性土剪胀性的细观认识  

Microscopic understanding of dilatancy in cohesionless soils

作　　者：雷国辉[1] 陈晶晶[1,2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,岩土工程科学研究所,江苏南京210098 [2]铁道第三勘察设计院集团有限公司地质路基设计处,天津300251

出　　处：《岩土工程学报》2011年第9期1333-1339,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(50878075);江苏省高校青蓝工程基金项目;中央高校基本科研业务费专项资金项目(2011B02814)

摘　　要：针对规则的椭圆形颗粒、圆形和履带形颗粒以及不规则形状颗粒组成的土体进行了平面力学分析,推导了应力比和塑性应变增量比表达式,建立了由土体本身内在材料属性,包括颗粒的形状、大小或级配、以及布局方式或组构,所决定的细观剪胀模型。分析结果表明,在建立状态相关的宏观剪胀理论时,状态的概念并不仅仅局限于描述土体颗粒布局方式的孔隙比状态参数,还应包括其它能够反映颗粒形状、大小或级配的宏观状态参数。Expressions for stress ratios and plastic strain increment ratios are derived from the planar mechanical analyses of soils consisting of particles of regular elliptical shape,circular and crawler belt shapes,and of irregular shapes.On this basis,a microscopic dilatancy model is established depending on the intrinsic characteristics of soil materials including particle shape,particle size or gradation,and particle packing or fabric.It is shown from the model analyses that when establishing the macroscopic state-dependent dilatancy theory,the concept of the state should not be limited to only the void ratio state parameter describing the soil particle packing.Other macroscopic state parameters capable of reflecting the particle shape,size and gradation should be also included.

关 键 词：剪胀 颗粒 布局 应力比 塑性应变增量比 

分 类 号：TU431[建筑科学—岩土工程]