ABSTRACT

The paper investigates the effects produced by the repetition of seismic events on steel structures. Two moment resistant frames with different number of floors and rigid joints, two frames with semirigid joints and a concentrically braced frame have been analysed under repeated seismic events of medium-strong intensity. Obtained results highlight that the seismic responses are characterised by a significant decrease in the behaviour factor with respect to only one event. These effects should be then taken into account in sites where such a type of event may occur, in order to avoid an excessive structural damage.