广义塑性本构模型三维化方法的研究与验证

Researchand verification of a generalization method for thegeneralized plastic model by true triaxial test

在二维空间中基于p、q分量构建的广义塑性本构模型无法反映中主应力对土石料变形特性的影响,因此需要将其进行三维化以反映出一般应力状态下本构关系。研究了多种三维化方法,通过与真三轴试验对比,基于广义非线性强度理论(generalized nonlinear strength theory, GNST)的三维化方法可以使本构模型较好地反映土石料一般应力路径下的应力应变关系。对某面板堆石坝进行的数值计算,并与监测结果对比,表明三维化后的本构模型能更好地反映堆石坝的变形规律。因此,基于GNST的模型三维化方法可以应用于高土石坝设计中,并可以获得较好的预测结果。

The generalized plastic constitutive model based on p and q components in two-dimensional space cannot reflect the influence of medium principal stress on the deformation characteristics of soil and stone,so it needs to be three-dimensional to reflect the constitutive relationship under general stress state.In this paper,several three-dimensional methods are studied.Compared with the true triaxial test,the three-dimensional method based on GNST can make the constitutive model better reflect the stress-strain relationship of soil and stone under the general stress path.The numerical calculation of a concrete face rockfill dam and the comparison with the monitoring results show that the three-dimensional constitutive model can better understand the deformation law of the reactor rockfill dam.Therefore,the 3D modeling method based on GNST can be applied to the design of high earth-rock fill dams,and better prediction results can be obtained.