Abstract: To solve the deficiency of the Duncan-Chang model in describing the mechanical properties of core wall asphalt concrete, a modified constitutive model for this material is presented. And a finite element analysis method is developed based on the real compaction quality of different dam materials, to better consider spatial variations in the compaction quality of dam materials during real construction that often results in spatial differences in their mechanical properties. First, a spatial estimation of compaction quality for different dam materials is made using construction data collected by a Digital Dam system. Then, we construct quantitative relationships between compaction quality and constitutive model parameters for different dam materials, and determine the constitutive model parameters of each element; Through a secondary development of Abaqus, a spatial estimation of constitutive model parameters for different dam material zones is realized. Finally, we make a fine numerical analysis of the structural behavior during the construction of an asphalt concrete core wall rockfill dam for a real project. The results show that numerical simulation based on the real compaction quality of dam materials can better describe stress and deformation distributions in construction process, and the modified constitutive model improves the calculation accuracy of core wall deformation. Thus, this study demonstrates an effective approach to accurate analysis of the structural safety of asphalt concrete core wall rockfill dams.

Key words: asphalt concrete core wall, rockfill dam, constitutive model, parameter spatial estimation, compaction quality, structural behavior