ABSTRACT
An original exact analytical closed-form solution for the seismic response of n-layers soil is exposed in this paper. Fundamental frequency of n-layers soil is obtained as a solution of a closed-form equation, having a condensed expression, explicit in terms of the soil properties, established for the multilayer soil. The displacement at any point of the soil is obtained by explicit formulas depending on the soil dynamic and geometrical properties, and fundamental mode frequency. Numerical applications for 2, 3, 4 and 26-layers soil profiles show comparative results with presently used approximate methods of Modules average, Dobry-Madera and Simplified Rayleigh Procedure. In fact, the presented method constitutes a general solution for n-layers soil seismic response and allows to compute frequency and modal shape for all eigenmodes. Results are shown for modes 1, 2 and 3 for the previously mentioned soil profiles.
