In recent years, the SI value and measured seismic intensity closely corresponding to earthquake damage have been introduced into operation control for when earthquakes occur, in addition to the conventional alarming acceleration (gal). To study methods of controlling train operation using new indices of seismic motion, therefore, the RTRI proposed formulae for conversion between the new and old indices, based on approximately 2,400 waveforms as observed by the Meteorological Agency and other public organizations (Figs. 1 and 2). As a means to quickly evaluate earthquake-damaged areas based on information from emergency earthquake alarms, the RTRI has also proposed a method of estimating the maximum distance Ģ to the damaged area based on earthquake damage data from recent years (Fig. 3). The RTRI has found that the minimum earthquake scale for which the damaged area can be evaluated using this method is about 80 gal (alarming acceleration), 6 kine (SI value), or a measured seismic intensity of 4.5 (the lower limit of magnitude 5).
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