RESPONSE MODIFICATION FACTOR AND INELASTIC BEHAVIOR UNDER INTRAPLATE EARTHQUAKES

It is shown that for systems with intermediate frequencies (i.e. ۴< f < ۱۰ Hz) subjected to an intraplate earthquake the ductility demand is consistently less than the design ductility. This is contrary to the observations for response of these systems when subjected to interplates earthquakes. For high frequency systems (f > ۱۵ Hz) the number of yield excursions and reversals becomes higher for intraplate earthquakes compared to interplates earthquakes. Furthermore, under intraplate earthquakes the number of yield excursions and reversals are not necessarily the highest for frequencies in the velocity region. The implications of these observations on the design is also discussed