No abstract

Web GIS-based support system for collecting and sharing information was developed and carried out by collaboration between a local government and residents at two stages; at the first stage, workshops by local communities' associations and government officers are held to make disaster mitigation maps, which indicate strong and weak points of the local area, such as the locations of fire distinguishers, fire hydrants, storages of -220 -rescue equipments, weak walls and buildings, open spaces, and so on. During the workshop, the participants also discuss about what happens during a large earthquake, and how to cope with the disaster. At second stage, an emergency drill is carried out by collaboration between the local government and the community residents. The developed system was applied to the workshops and the earthquake drill in Toyohashi City in 2006, and confirmed its validity and effectiveness.

Currently used Japanese seismic intensity based on measurement value by mechanical instrumentation, which is called measurement seismic intensity and not always affects human body feeling and earthquake damage. The measurement seismic intensity represents local ground motion characteristics at an observation point due to the foundation and geology conditions and is difficult to evaluate the seismic intensity at a point between observation points. The questionnaire seismic intensity can be said to be very effective in the point. Therefore, in this research, the questionnaire survey to investigate areal ground motion characteristics in two cities in Miyagi prefecture during the 2011 off the Pacific coast of Tohoku Earthquake and its one of aftershocks on April 7, 2011. One is Ohsaki city of which central area was suffered from serious damage in the main shock. The other is Kurihara city including the Tsukidate area where serious damage in the main shock. The other is Kurihara city including the Tsukidate area where serious damage was not recognized even if the seismic intensity scale was 7 during the main shock.