Mass ratio factor for optimum tuned mass damper strategies

• Mass ratio factor was investigated.
• Conventional expressions are related to mass ratio.
• Various periods and mass ratios were considered.
• Harmony Search (HS) is proposed to find optimum parameters of TMD.
• Tuned parameters are more feasible in HS.

Conventional expressions proposed for the optimum design of tuned mass dampers (TMD) are a rapid source to reach the information on frequency and damping ratios. These expressions are related to a preselected mass ratio. The effect of mass ratio was investigated by conducting analyses carried out under different earthquakes records for SDOF structures with various periods. Results showed that mass ratio, external excitation and period of the structure are effective on the performance of the TMD. Also, the usage of the expressions is not feasible in some situations. For that reason, a metaheuristic algorithm called Harmony Search (HS) was employed to find more feasible results. The comparisons between proposed method and simple expressions showed that the optimum parameters are more economical and feasible for HS approach.