気象庁震度階と地震動強さの物理量との関係

抄録

To clarify physical meanings of seismic intensity scale and to make seismic intensity data more applicable in seismological and earthquake engineering studies, the correlation of Japan Meteorological Agency (J. M. A.) intensity scale with physical parameters of earthquake motion has been investigated. The total number of ground motion data used is 226 sets. These data cover the J. M. A. intensity of O to V. Results from the analysis of these data are as follows: (1) The correlation of intensity with horizontal motion is higher than that with the vertical in high intensity range, but is almost same as that with the vertical in low intensity range; (2) At low intensity range, high frequency motion with frequency of around 5Hz shows higher correlation with intensity, but the lower frequency motion with frequency of around 2Hz shows higher correlation in high intensity range; (3) At high intensity range, the contribution of duration time to intensity could be recognized; (4) The above-mentioned results are come from the difference in the objects to define the intensity at each intensity level; and (5) From low to high intensity range, peak ground acceleration shows relatively high correlation with intensity, but in high intensity range which has more significance in earthquake engineering problems, peak ground velocity or total power of ground acceleration shows higher correlation.