Numerical Study of the Effect of Structure on Ground Response

Abstract

Multiple interactions between the site - city under the effect of seismic waves change the soil and structural responses in various aspects. So far, several studies have been conducted on the effects of structural and geotechnical parameters on the site response; focusing on one or more aspects of this subject. The results of this research can be used in several topics including modification of the ground response in urban areas, as well as seismic design of buildings. In the present study, the effect of multiple interactions between the buildings and the site has been investigated more comprehensively and completely and the required concepts have been extracted more precisely. This was done by utilizing OpenSees; a powerful finite element software. Two-dimensional model of a site was built and buildings also were modeled ideally as separate blocks. The blocks were attached to the soil model using spring elements. The results of this model were compared with those of previous research indicating a good consistency and accuracy of the current model. Then, the effects of various parameters on the responses of soil were studied. The parameters used in the sensitivity analysis include the number of structures, structural dimensions including width and height, soil shear wave velocity, and different distances from blocks affecting ground response. The study showed that by increasing the number of buildings, the amplification ratio at a distance of 4 meters from the location of the structure is reduced. Also, by increasing the width of the foundations, the scope of the effect of structure on ground responses increases almost with a specific ratio.

Keywords: Site-city interaction, ground response, free field, the effect of structure, amplification