Optimum parameters for adjacent structures coupled by fluid viscous dampers considering soil‒structure interaction

In this paper, the optimum conditions which ensure that the resulting minimum base shear force and minimum roof displacement for two adjacent frame structures inter-connected by fluid viscous dampers, including soil-structure interaction (SSI) effects under seismic excitation were presented. A two-dimensional (2D) finite element analysis was carried out with the Taguchi method. As non-reflecting boundaries, vis-cous boundary conditions were used on the edges of finite soil region. An optimization study was carried out for four parameters such as soil type, height ratio of the frames, damping coefficient of viscous damper, and the location of the viscous damper each with four levels. The optimum conditions which minimize maximum roof displace-ments and the maximum base shear forces have been obtained. The most affecting parameter on the system response was found to be soil type. It was also found that the sufficient damping coefficient of the viscous damper is equal to 1x105 N.s/m for min-imum response. The minimum system response can be achieved by using only one damper. It can be drawn that the Taguchi method can be used with the finite element (FE) method for determining optimum conditions of a soil-structure system for min-imum system response.