A Prediction Model for Deformation Behavior of Concrete Face Rockfill Dams Based on the Threshold Regression Method

Rapid prediction of deformation behaviors of concrete face rockfill dams (CFRDs) is of great significance in guiding their design and construction. The purpose of this study is to develop robust empirical prediction models with physical significance, which can rapidly predict typical deformation behaviors of CFRDs. Based on 87 case histories of in-service CFRDs, the threshold regression theory is used to develop empirical relationships between three typical deformation indices (maximum crest settlement, maximum internal settlement, and maximum face slab deflection) and six dam-construction-related influencing factors (dam height, intact rockfill strength, foundation behavior, valley shape factor, void ratio, and operation time). The internal correlations between the deformation behavior and influencing factors are discussed. The importances of the influencing factors for each deformation behavior are quantitatively evaluated. The threshold regression models are developed to predict typical deformation behaviors of CFRDs. The developed models are compared with the existing methods to discuss their rationality and accuracy.