Numerical analysis of stress and deformation of concrete face rockfill dam based on sub-model method

The mid-point incremental method was used to carry out 3D FEM analysis for a CRFD project called Miaojiaba based on Duncan-Chang(E-B) nonlinear constitutive model and the filling construction and retaining water process of the dam was also considered.As a result,a corresponding general law of the dam's stress and deformation distribution during construction and storage period were obtained.Judging from the view of the dam structure,the rockfill dam body works reliably.In order to get more accurate results of the face and its joints' stress and deformation,the developed 3D sub-model method was applied to the calculation with the coupling thin-layer element to simulate the specific boundary between face and cushion.According to the results of engineering example,the stress and deformation distribution of the dam conforms to the general law.The concrete face also has a normal stress and deformation law that distribution of larger tensile stress is restricted to blanket protected area.The deformation of transverse joints and peripheral joints is small,which indicates that the concrete face works well and safely.At the same time,it is further proved that the sub-modeling method with the coupling thin-layer element to simulate the contact face is feasible and believable.