A DISCUSSION ON THE RELATIONS OF SITE EFFECT AND DAMAGE OFWOODEN HOUSES USING WITH MICROTREMORS IN FUKUI PLAINAFFECTED BY THE 1948 FUKUI EARTHQUAKE

摘要

Authors observed microtremors in Fukui Plain to discuss on the relationships between dynamiccharacteristics of surface geology and the damages of wooden houses caused by the 1948 FukuiEarthquake. By the distribution maps of predominant periods using H/V spectral ratio and damagedratios of wooden houses, the distribution of the short periods corresponded to the low damagedratios. And the areas of predominant long periods distributed on alluvial deposit in the western partfrom the earthquake fault. The high damage ratios at the sites of alluvial deposit are located within8km from the earthquake fault, but the ratios decreased and varied widely in the areas farther than8km. The predominant periods are related with the thickness of alluvial deposit. We can concludethat the earthquake damages were related with the dynamic characteristics of surface geology in thisarea.