ABSTRACT
Using a SDOF system consisting of a primary subsystem and a secondary subsystem, shown in Fig. 2, as a model of these structure, Iyama and Kuwamura (1999) showed that a change of the natural period of such a system due to a fracture of the primary subsystem may improve the seismic performance in a probabilistic point of view when predominant period of input ground motions are variable. However, this study was based on an assumption that the secondary subsystem would not collapse after the first fracture in the primary subsystem, that is, the total system was always “fail-safe”.
