An internal input framework of earthquake motions for dam-water-foundation rock systems

The input mechanism of earthquake motions is a key issue for the seismic analysis and safety evaluation of dams. Although various methods for inputting earthquake motions and recognizing semi-unbounded domains have been proposed, the implementation of existing methods requires users to handle complicated pre-processing works. In this paper, a general internal input framework of earthquake motions is integrated for dam-water-foundation rock systems, which consists of an internal input method and the equivalent viscous-spring finite element boundary. The internal input method is implemented by the internal substructure method (ISM). It is proved that the effective seismic forces in the domain reduction method can be converted into those in the ISM, and thus they can be obtained by one auxiliary dynamic reaction calculation. The equivalent viscous-spring finite element boundary is constructed by general finite elements instead of springs and dampers. The proposed integrated framework is user-friendly for most finite element codes and can significantly save efforts during pre-processing.