Optimization of Semi-Active Control of Seismically Excited Buildings Using Genetic Algorithms

In this paper, the performance of semi-active viscous dampers in reducing the response of tall buildings to earthquake acceleration is optimized using genetic algorithms. Torsional effects due to irregularities exist in the building and due to unsymmetrical placement of the dampers are taken into account through 3-D modeling of the building. For the numerical example, a twelve-story building is chosen. The building is modeled as a 3-D frame. The equations of motion of the building with semi-active viscous dampers, subjected to earthquake acceleration, is written, resolved in state space and the results are compared with those of the uncontrolled building. Moreover, in order to minimize building responses such as top story displacement and base shear, the required number and location of dampers are optimized using genetic algorithms.