Abstract
In this study, we investigated the condition and the size of cracks caused by the 2005 West off Fukuoka Earthquake on various types of objects such as wooden house, concrete building, fence and floor and road in Fukuoka urban area and analyzed the data of cracks by GIS. We made a damage distribution map on the earthquake from the results of the analysis and discussed the relationships between that and geologic and geomorphologic conditions. We clarified the followings through this study.
1) We converted the points of condition and the size of cracks into 7 ranks of a unified standard based on these related setting between various types of objects in a small area, so we could make a damage distribution map with mostly objectivity.
2) The damages were large at the seaside area, the east area of Kego fault and the surface of the ground of buried valleys where the basement rock is deep. They were small at the surface of the ground over the underground convex landform of basement rock and near hills where the basement rock is shallow.
3) The damages were small at terrace, natural levee and alluvial plain. On the other hand, they were large at hills and the landforms near seaside such as reclaimed land since the World War II, coastal lowland and dune.
4) We referred to the concept of quantitative evaluation on a borehole wall and an outcrop in engineering geology for a unique compiling method on a damage distribution map.
We had better to study other cases for the map because the 7 ranks of a unified standard in this study are not sufficiently general.
