مطالعه آزمايشگاهي (ميز لرزان ) اثرات اندركنش خاك سازه در پاسخ لرزه اي ساختمانهاي مجاور هم

Shake Table Study of Soil-Structure Interaction Effects on Seismic Response of Adjacent Buildings

In this paper the effect of soil-structure interaction in seismic response of adjacent buildings is studied using shake table scale model tests. Four structural models of 5, 10, 15 and 20 stories high and two relatively soft soil models were designed for the laboratory tests. The foundation system for structural models was considered as square rigid mats. A special container was designed and constructed to support the soil model with special emphasis on easy connection to the shake table. This container also provided sufficient environment to allow for the elastic half space of the soiL There was a good agreement between shaking table test results and finite element analyses. From the experimental and analytical results, it can be concluded that the effects of kinematic interaction is negligible in comparison with inertial Interaction. In buildings lower than 5 stories high, the horizontal and rocking mode of foundation were known to be the main causes of soil-structure interaction. but in taller buildings, the rocking mode was the dominant one. The major effects of soil-structure interaction were found to be increasing first mode period and damping ratio of the structure. Cross-interaction of adjacent buildings was seen to be more important in high frequency ranges in comparison to low frequency ranges. In addition, these effects were considerable in similar and near adjacent buildings.