A Constitutive Model Of Rockfill And Its Discuss And Validation

Concrete face rockfill dam(CFRD) is one type of rockfill dam, its main supporting structure of dam body is the rockfill structure, and its main impermeable structure is the concrete panel set at the upstream side of the rockfill structure. It has many advantages such as lower construction cost, shorter construction period, more simple construction method, and higher adaptability to the terrain features. In recent years, CFRD has developed quickly and became widely used in many parts of the world, especially in china.In the stress and deformation numerical analysis with finite element method(FEM) of CFRD, as the main component of the dam, the stress and deformation numerical analysis of rockfill is particularly important. The constitutive model is the base of numerical analysis of stress and deformation, so it is particularly important to select an appropriate constitutive model of rockfill to support the stress and deformation numerical analysis of CFRD.After studying and analysing Duncan-Chang E-B model and Tsinghua university nonlinear K-G model, this paper puts forward the K-νmodel. It is established with volume modulus and tangent poisson's ratio. Compared with Duncan-Chang E-B model and its former form, the E-νmodel, K-νmodel introduced and optimized Duncan's compute method of tangent poisson's ratio; Compared with Tsinghua university nonlinear K-G model, K-νmodel introduced the compute method of strength criterion and volume modulus, but cut off the shear modulus who can determine exactly only by constant ratio of principal stress path experiment, and established the stiffness matrix by this volume modulus and tangent poisson's ratio. But limited by the experiment data, this paper didn't finish the compute method of tangent poisson's ratio when unloading and the loading-unloading conditions judgment. So now K-νmodel is just an unfinished constitutive model and need more research.K-νmodel program was developed with the interface of constitutive model of the MSC. Marc software development platform, and validated by the analysis of Shuibuya CFRD 2D model. Results show that K-νmodel can adapt to the FEM analysis of CFRD.Stress and deformation with FEM analysis using K-νmodel of Shuibuya CFRD and Pankou CFRD 3D model were finished. Compute results show that K-νmodel can adapt to real project analysis.