抄録
This paper presents an overlay analysis of water supply pipe damage in Cities of Nagaoka and Ojiya, Niigata Prefecture where large damage of lifeline systems due to the 2004 Niigata-ken Chuetsu Earthquake was reported. Primary factors to damage were analyzed by entering damage information of the water supply pipes to GIS and overlaying some digital maps including geomorphologic classification, liquefaction, and landslide. The results of analysis show that the damage of the pipes was concentrated within alluvial fans and gravelly terraces along the boundaries of geomorphologic map units such as between alluvial low lands and terraces or hills in the west zone along the earthquake source fault. In Ojiya City the damage rate in the liquefaction zones is about 1.5 times higher than that in other regions.
