Deformation characteristics during construction and after impoundment of the CFRD-type Daegok Dam, Korea

• We analyzed monitoring results during CFRD construction and initial impoundment.
• We simulated dam behavior numerically using parameters based on laboratory tests.
• CFRD case histories were analyzed along with a few empirical equations.

The deformation characteristics of a concrete-faced rock-fill dam (CFRD) during the dam's construction and initial reservoir filling phases were investigated. A detailed examination of behavior of a CFRD during the construction stage was conducted for the CFRD-type Daegok Dam located in Korea, where a well-designed monitoring program was planned. The monitoring record obtained during the dam construction and initial impoundment is presented. The vertical displacements during dam embankment are compared with other CFRD cases in Korea. Two-dimensional finite element analyses were performed to assess the displacements during both the construction and initial reservoir filling stages, using the model parameters estimated based on large-scale triaxial tests. A nonlinear and inelastic constitutive soil model was used to represent the behavior of the rock materials. In addition, the monitoring results for 29 CFRDs were analyzed. The observed and predicted values on the normalized maximum displacement and the location of maximum values during the dam construction stage agree well. Also, the limitations of numerical analysis on the reservoir filling stage are addressed.