RESUMO
A method which evaluates soil-structure interaction effects is presented. The method consists of an equivalent oscillator which includes the effects of the interaction, modifying its original fundamental period and damping. The new oscillator is treated like a replacement oscillator in the system with rigid base. The response contours concept displays the site effects and the soil-structure interaction at the same time, in terms of both the dominant site period and the fundamental structural one. Response contours profiles depict response spectra with soil-structure interaction at different sites. Response contours are evaluated for different sites and different structure configurations, typical of Mexico city. Results of parametric analyses illustrate the importance of key parameters in soil-structure interaction effects, such as the depth of soil deposit, the embedment of the foundation and the slenderness of the structure.(AU)