Discussion of paper: “Estimating optimum parameters of tuned mass dampers using harmony search” [Eng. Struct. 33 (9) (2011) 2716–2723]

In the aforementioned paper, the optimum parameters of tuned mass dampers (TMD) are determined by the Harmony search (HS) algorithm in multiple degree of freedom (MDOF) structures under seismic excitations. The proposed approach is original; however, the mechanical model for the damped structure is not in agreement with previous results reported in the literature. Thus, the main focus of this discussion is to highlight the differences and analyze the impact on the obtained results.