An attempt to recalibrate instrumental criteria for intensity assessment

Abstract

The authors contributed during a quite long period of time to the development of comprehensive and flexible system of estimating seismic intensity on the basis of instrumental (accelerographic) data on earthquake ground motion. The system makes it possible to determine for a record, according to needs, global intensities, intensities corresponding to definite frequencies, intensities averaged upon a spectral band, continuous or discrete intensity spectra. Moreover, the intensity measures developed may rely, according to choice, on different outcomes of processing of primary instrumental data. A problem to which the paper is devoted is represented by the calibration of an important parameter, namely the logarithm base adopted in view of conversing instrumental information to intensity measures. After the attempts of the past, new sources are used this time to solve the problem. Alternative solutions are examined and discussed in this view