Multi-objective optimisation of damper placement for improved seismic response in dynamically similar adjacent buildings

Multi-objective optimisation of damper placement in dynamically similar adjacent buildings is considered with identical viscoelastic dampers used for vibration control. An exhaustive search is used to describe the solution space in terms of various quantities of interest such as maximum top floor displacement, maximum floor acceleration, base shear and inter-storey drift. With the help of examples, it is pointed out that the Pareto fronts in these problems contain a very small number of solutions. The effectiveness of two commonly used multi-objective evolutionary algorithms, viz. NSGA-II and MOPSO, is evaluated for a specific example.