Abstract: The accuracy of numerical simulations of the deformation of high rockfill dams, represented by the finite element method, depends on the constitutive model. This paper develops a practical nonlinear elastic constitutive model incorporating dilatancy, namely the EBD model, for rockfill dam deformation simulations based on the Duncan-Chang EB model. Using the deformation monitoring data of the Aertashi concrete faced rockfill dam, we design three inversion cases and obtain the optimal parameters of both the constitutive EB model and EBD model via inversion analysis. Then, corresponding triaxial compression tests are simulated numerically and compared against experimental measurements. The results indicate that at the structural level, the traditional EB model is not acceptable when the distributions of both settlement and horizontal deformation are simulated, while the EBD model improves the simulation accuracy of horizontal deformation while maintaining the accuracy of settlement. We find the EB model parameters that allow for acceptable deformation simulations will result in poor simulations of element level stress-strain behaviors. In contrast, the EBD model can achieve good simulations of dam deformation and element level stress-strain behaviors simultaneously.

Key words: rockfill dam, constitutive model, dilatancy, deformation monitoring, inversion analysis, triaxial test