عنوان مقاله [English]
Simultaneous effects of soil and several structures are known as the site-city
interaction (structure-soil-structure interaction), which is very important in
areas with high construction density and has been considered by many scholars
over the past two decades. Site-city interaction can affect the structure behavior due to the wave propagation between structures. In fact, it decreases the structure responses in some cases, while it increases the responses in some other cases. Many parameters play a role in assessing site-city interaction such as the gender of soil, number and arrangement of structures, height of buildings, shape of earthquake waves, and the main period of structures and soil. The present study aimed to evaluate the effects of gender and solidity of the soil based on 2800 standards and building distances in site-city interaction in three dimensions. The effects of these parameters on the foundation and top of structure responses including maximum acceleration values and Root Mean Square acceleration were assessed. SASSI 2000 software was employed to model structures and soil and analyze the system. In this study, structural models were considered in both single structure and the ideal city (structural groups). The groups were $3times 3$
including nine identical structures. In the single model, the site-city interaction was not considered, and these effects were considered in the group model. Lumped-Mass Stick Model was used to model each structure and the soil, which was modeled in the software including a semi-infinite elastic environment with horizontal layering, located on the viscoelastic half-infinitely semi-space. Based on the results, regarding the top of structure, the existence of structures alongside each other by considering site-city interaction effects in different soils resulted in decreasing the structural acceleration responses (25% average) compared to the individual structure site-city interaction effects, which increased by decreasing the soil stiffness (5-10% average). Further, the effects of multiple structure-soil-structure interaction decreased (10-15% average) by increasing the distance between structures.