TIME-DOMAIN RESPONSE OF A ONE-DIMENSIONAL SOIL-STRUCTURE INTERACTING MODEL VIA COMPLEX-ANALYSIS

This paper considers a simple continuous model which embodies some asp ects of the dynamic soil-structure interaction problem. For this model the equations of motion are first written, then complex frequencies a nd eigenmodes are evaluated. A physical interpretation of complex mode s and frequencies is also provided, Subsequently a set of orthogonalit y conditions is established and is used in decoupling the equations of motion in principal coordinates. The complex mode superposition metho d is then used to provide the dynamic response of the model in the tim e domain. Some numerical applications are provided in order to show th e performance of the method.