“…It is suited for full graphic development, providing increased control and insight into the dynamic behavior of irregular systems. The identification of synthetic structural and modal parameters in the linear range can be critical for the choice of spectrumbased intensity measures governing the response of building systems also in the nonlinear range, [10], [11]. New graphical features are presented as well as a validation of the GRSA method for predicting the directional response in terms of 'eight-shaped' modal influence circles.…”