14 - Optimization of Tuned Mass Damper with Harmony Search

Abstract

Harmony search (HS), a metaheuristic optimization method that has been successfully proven by optimizing several engineering problems, is a suitable algorithm for tuning passive mass dampers on structures. By adapting HS to a tuned mass damper (TMD) problem, the optimum mass, stiffness, and damping coefficients of TMDs are proposed under external excitations. The physical and economical restriction can be also taken into account by limiting the soloution ranges. Considering physical and economic conditions is not possible by using the closed form expressions depending on a preselected damper mass. A program can be developed for numerical optimization and time domain simulation by using different optimization strategies. The method was presented by analyzing two examples. In the first example, the optimization process was conducted under a sinus loading for a fast and general optimization. The other example was analyzed under earthquake excitations for specific conditions. The optimum TMD parameters were checked under benchmark earthquakes, which were not considered during optimization. Also, the optimum results of the first example were compared with several other documented methods. Comparisons show that the HS approach is more effective than other documented methods in reducing structural vibrations and more feasible due to suitable TMD parameters according to physical and economic conditions.