adina土的模型(双语).doc

3.9 Geotechnical material models 地质材料模型 3.9.1 Curve description material model曲线描述的材料模型 ? The curve description model can be employed with the 2-D solid (plane strain and axisymmetric) and 3-D solid elements. 曲线描述的材料模型可以用于二维实体（平面应变及轴对称的）和三维实体单元 ? The curve description model can be used with the small displacement and large displacement formulations. In all cases, small strains are assumed. When used with the small displacement formulation, a materially-nonlinear-only formulation is employed, and when used with the large displacement formulation, a TL formulation is employed. 曲线描述的材料模型可以用于大变形和小变形分析。在任何情况下都假设为小应变。当用于小应变分析时，使用材料非线性分析；当使用大应变分析时使用的是TL分析。 ?The curve description model is a simple incremental stress strain law used to represent the response of geological materials. The model describes the instantaneous bulk and shear moduli as piecewise linear functions of the current volume strain, as shown in Fig. 3.9-1. An explicit yield condition is not used and whether the material is loading or unloading is determined by the history of the volume strain only. 曲线 描述模型是单值的应力应变规律，通常用来表示地质材料。模型用实时体积的分段线性函数描述了材料的瞬态体积和剪切模量，如图3.9.1所示。不需要直接的屈服条件并且是否受荷取仅仅取决于材料体积应变得历史。 ? To present the governing constitutive relations, let ＝total strains (the left superscript t always refers to time t) 总应变（左上标t表示时间t） ＝incremental strains 应变增量 ＝＝mean strain (negative in compression) 平均应变（忽略压缩） ＝= incremental mean strain 平均应变增量 ＝= deviatoric strains 偏应变 ＝incremental deviatoric strains 偏应变增量 ＝total stresses (negative in compression) 全应力 = incremental stresses 应力增量 ＝= mean stress 平均应力 ＝= incremental mean stress 平均应力增量 ＝minimum mean stress ever reached 曾经达到的最小平均应力 ＝＝deviatoric stresses 偏应力 = incremental deviatoric stresses 偏应力增量 ＝shear and bulk moduli 剪切及体积模量 The incremental stress-strain relations using the curve description model are then 使用曲线描述的应力-应变增量关系是： ＝2 ＝3 ?The instantaneous bulk and shear moduli, tK and tG, are functions of the loading condition, and the volumetric strainis define