Earthquake Soil Structure Interaction Analysis of a Gravity Dam H. Yang, H. Wang, J. W. Salamon, and B. Jeremic Abstract This paper presents numerical modeling and simulation issues seen in static and dynamic analysis of dam-foundation systems. Domain reduction method (DRM) is chosen as the preferred approach for seismic motion input. Proper modeling of inelastic material behavior and seismic energy dissipation is discussed. Verification and validation are essential to ensure reliability of numerical results. Numerical modeling and simulation of a soil/rock—concrete dam system subjected to static and dynamic earthquake loading are presented. It is shown that, in order to make safe and economical design decisions, engineers should have complete understanding and control of the numerical analysis process. Keywords Earthquake soil structure interaction · Dam modeling · Nonlinear finite element · Seismic energy dissipation · Verification and validation 1 Introduction Credibility of numerical analysis results relies to a great extent on a number of numer- ical modeling and numerical simulation issues. Those issues need to be properly addressed and resolved so that Earthquake, Soil/Rock, Structure Interaction (ESSI) analysis for dams produce rational, reliable results that can be used for design and assessment. Some of those issues are briefly presented in this short paper. More detailed account of modeling and simulation of ESSI behavior of a soil-structure systems is presented by Jeremi´ c et al. [1]. H. Yang · H. Wang · B. Jeremic (B ) University of California, Davis, CA 95616, USA e-mail: jeremic@ucdavis.edu J. W. Salamon United States Bureau of Reclamation, Denver, CO 80225, USA © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2021 G. Bolzon et al. (eds.), Numerical Analysis of Dams, Lecture Notes in Civil Engineering 91, https://doi.org/10.1007/978-3-030-51085-5_20 369