MULTIPLE STRUCTURE-SOIL- STRUCTURE INTERACTION AND COUPLING EFFECTS IN BUILDING CLUSTERS

We study the presence of multiple structure-soil-structure interaction effects in idealized building clusters during earthquakes, their effect on the ground motion, and how individual buildings interact with the soil and with each other. We seek to characterize, through a parametric approach, the coupling effects between the soil, the foundation, and the structural response of the buildings, including torsion, in the presence of surrounding structures. We simulate the ground motion of a historical earthquake and focus on the response of simplified symmetric and asymmetric building models located on soft soil. We use as reference the response of isolated symmetric and asymmetric building models, which allows us to separate the different contributing factors and distinguish between individual soil-structure and coupled structure-soilstructure interaction effects. Numerical results show that coupling effects vary with the number and dynamic properties of the buildings, their separation, and their impedance with respect to the soil. Our results indicate that the effects of torsion are also relevant. Interaction effects appear as an increased spatial variability of the ground motion, and significant reductions in the buildings’ base motion at frequencies above the natural frequencies of the building-foundation systems.