Soil dynamics is a moderately new branch of geotechnical engineering that has attracted huge attention in the past two decades or so. Voluminous research publications are the result of exhaustive investigations on the part of researchers in both academia and industry. In the seismic analysis of a structure founded on ground, the ground motion passes to the base of structure and then loads on structure. The response of the foundation system affects the response of the structure and vice versa, which is called dynamical soil-structure interaction. In the seismic resistant design of structures, we are most interested in the strength reduction factors to account for the nonlinear behavior that might be experienced by a structure subjected to an earthquake ground motion. Few researchers have recently attempted to assess the effect of SSI on the strength reduction factors, which is primarily controlled by the changes in the structural period and displacement ductility. This book investigates soil-structure-interaction effects considering nonlinearities occurring at the soil-foundation interface. Soil Dynamics and Foundation Modeling presents a comprehensive new concepts and techniques on soil dynamics and foundation modeling in offshore and earthquake engineering with both theory and realistic applications, and thoroughly links the practical approaches with engineering applications. It contains material pertaining to soil dynamics, earthquake engineering, and special design aspects of geotechnical engineering with basic dynamic properties of soils, machine foundations, dynamic and vibratory compaction, and pile driving response. It also reflects on new findings from research results based on recent case histories. This book will be of valuable for students, researchers, and practicing engineers, interested in this field.