The Evaluation of Effective Period of Buildings Including Soil-Foundation-Structure Interaction Effects

The aim of this paper is to propose a simple and reasonably accurate method for determination of modal periods of structure including soil-foundation-structure interaction (SFSI) effects. Mylonakis and Gazetas (2000) reported that Mexico earthquake was particularly destructive to 10-12 storey buildings founded on soft soil clay, whose period increased from about 1.0 s (assumption of fixed base structure) to nearly 2.0 s due to the SFSI. This conclusion demonstrates the effects of higher mode on the response of structure. In this paper, The results indicate for a constant depth of embedment and soil shear wave velocity, the actual modal period become a few smaller than proposed method of modal period and the proposed mode is efficient in the modal analysis.

Keywords:

Modal Period , SFSI , Impedance Function