In this paper, comparative parametric analyses with fishbone shaped model considering strength deterioration of members are conducted in order to investigate the complete collapse behavior of steel moment frames. COF and widththickness ratio et al. are adopted as parameters. In a lot of cases, the collapse mechanism varies from the total collapse type to the story-collapse type due to strength deterioration by local buckling. The analytical results show that the collapse mechanism at the time of the complete collapse affects the energy capacity. Furthermore, the methods to estimate the capacity using the results of pushover analysis are proposed.
