HR: 15:45h
AN: S54A-02    [Abstracts]
TI: Topographic feature of the disasters along the railway by the Niigata Chuetsu Earthquake in 2004
AU: * TOMORI, M
EM: tomori@jreast.co.jp
AF: East Japan Railway Company, 2-0,Nisshin-cho,Kita-ku, Saitama, 331-8513 Japan
AB: The damage of the railway relation by the Niigata Chuetsu Earthquake which occurred on October 23, 2004 was serious. The main damage is derailment of a Joetsu Shinkansen Line, damage on a viaduct or a tunnel, failure of slopes or fills, etc. In order to grasp the actual state of failures around slopes or fills along the railway line, we carried out interpretation using the high resolution digital aerial photograph taken immediately after the occurrence of an earthquake. Next, a topographic feature of the failure was analyzed quantitatively by using 1m-DEM (Digital Elevation Model) made from the LIDAR(LIght Detection And Ranging) system. This report presents an overview of the topographic analysis result for Joetsu Line in which the numbers and size of failure were especially large. The topographical feature of the study area consists of mountainous area called the Uonuma hill and a terrace which develops into along Shinano River and Uono River. This area is characterized by the folding structure which has the axis of the direction of north-northeast-south-southwest. The outline of an analysis result is as follows. (1) Most cases of disaster were surface failure. (2) Many failures occurred in the terrace scarp along the river terrace of Shinano River and Uono River. (3) Landslide topography is widely distributed over this area, and many failures occurred in it. (4) The main aspect of the slope where failure occurred is the same as the direction of dip of stratum (northwest - west). (5) Many failures occurred on the convex or ridge type slope which is generally said to be easy to collapse in case of an earthquake, but also occurred on the concave or valley type slope. The influence of the rainfall before the earthquake can be considered as this reason.
DE: 5470 Surface materials and properties
DE: 7212 Earthquake ground motions and engineering
DE: 7299 General or miscellaneous
DE: 8040 Remote sensing
SC: Seismology [S]
MN: 2005 Joint Assembly