Abstract: Concrete dam-foundation dynamic interaction plays an important role in the earthquake response analysis and safety assessment of the high concrete dam. Based on perfectly matched layer (PML) theory, the wave equation and finite element equation of perfectly matched layer artificial boundary in time domain are deduced and implemented. The accuracy and stability of PML artificial boundary simulation of far-field radiation damping is verified through the problem of wave absorption under the transient dynamic load. The reliability and validity of the ground motion input model based on PML artificial boundary is verified based on domain reduction method (DRM) and PML artificial boundary. A retaining dam section of a concrete gravity dam is considered. The results of PML artificial boundary and seismic input model, traditional massless foundation model and viscous-spring artificial boundary model are compared. It is found that the peak values of the horizontal and vertical relative displacement of the dam crest with the PML artificial boundary are reduced by about 40.6% and 31.7% when compared with those of the massless foundation model, and the relative peak displacements of PML artificial boundary are close to those of viscous-spring artificial boundary, which provides reference for analysis of dam seismic response and reasonable seismic input.

Key words: perfectly matched layers, dam-foundation dynamic interaction, domain reduction method, seismic input, seismic response of gravity dam.