Purpose and Background: Soil dynamics is the branch of soil mechanics which deals with the behavior of soil and foundations under dynamic loads. Operation of rotary machines or hammers, and earthquake ground motions constitute a class of dynamic loads that usually challenge engineers in their design of different kinds of foundations. The main goal of this seminar is to provide a better understanding to practicing engineers and architects of the design and evaluation of foundations under this class of dynamic loads. Topics to be discussed include: Basic Principles of Soil Dynamics: Fundamental distinctions between static and dynamic problems; basic notions of soil dynamics; the nature of different types of dynamic loads; the significance of soil-structure interaction; dynamic soil properties. Dynamic Properties of Shallow and Pile Foundations: Impedance functions of foundations and pile groups; definition of stiffness, and damping, for circular shallow foundations and piles; non-circular shallow foundations; mathematical models for pile analysis. Rotating Machine and Hammer Foundations: Harmonic excitations due to rotary machines; response of rigid foundations in 1DOF; evaluation of the effects of vibration; coupled response of rigid foundations in two degrees of freedom; types of hammers and hammer foundations; design criteria; mathematical models; impact forces and impact eccentricity. Vibration Damage and Remedial Measures for Machine Foundations: Damage and disturbance; problem assessment and evaluation; remedial principles; examples from different industries; sources of error. Geotechnical Earthquake Engineering Fundamentals: Sources of seismic hazard; introduction to seismic waves; ground motion characterization and response spectra; evaluation of soil dynamic properties; site response analysis. Design of Foundations for Seismic Loads: Dynamic bearing capacity of shallow foundations; dynamic response analysis of shallow foundations; conventional methods of analysis of piles under seismic loads; seismic analysis of deep caissons; seismic design of retaining walls; solved examples from industry. Computer applications using DYNA-5: Types of foundations; types of soil models; types of loads; types of analysis and output; practical applications using DYNA-5.