Long-Term Deformation Analysis of the Jiudianxia Concrete-Faced Rockfill Dam

Creep deformation of rockfills affects anti-see page systems, such as concrete face, toe slab, and peripheral joint. In particular, it may cause structure damage, such as water stop failure and concrete face cracking, especially in a high concrete-faced rockfill dam (CFRD) on a deep overburden layer. In this paper, viscoelastic constitutive models for concrete materials and bedrocks (a new creep constitutive model for rockfills) are introduced. A comprehensive study method on the stress and deformation of a high rockfill dam on a deep overburden layer is established based on field plate loading tests, laboratory triaxial creep tests, and prototype monitoring data analysis. The long-term deformation characteristics of Jiudianxia CFRD with complex topography and geological characteristics are analyzed and forecasted by using three-dimensional nonlinear finite element model analysis considering the effect of creep. The deformation of the dam shows an evident increment compared with that without considering the creep effect. Rockfill creep obviously influences the deformation and stress of the concrete-face slab. Meanwhile, comparative study of numerical calculation results and monitoring data showed good agreement between the computed settlements and measured values. Overall, the creep model and the adopted parameters are demonstrated to be reasonable, and the deformation of Jiudianxia CFRD is basically stable.