Field Reconnaissance: 16 November 2004

Damage Observations throughout Affected Area

Robert Pack, Ellen Rathje, Randy Jibson, Keith Kelson, and James Bay

GEER Beyond Reconnaissance Team

The GEER Beyond Reconnaissance Team traveled to the affected region from Tokyo on November 16. The team was accompanied by Prof. I. Towhata of the University of Tokyo, and several students from the University of Tokyo and Tokyo Denki University. The team visited damage sites in Kawaguchi, Ojiya, and Nagaoka.

Fig. 1. Overview of area where track of JR Joetsu line was damaged due to landslide debris, near Horinouchi. (37.258N, 138.892E)

Fig. 2. Illustration of track deformation. (37.258N, 138.892E)

Fig. 3. Removal of landslide debris from tracks (37.258N, 138.892E)

Fig. 4. Another view of removal of landslide debris from tracks (37.258N, 138.892E)

Fig. 5. Head scarp of landslide that took out road, railway, and pipeline in Kawaguchi along Route 17 (37.291N, 138.836E)

Fig. 6. View of roadway displaced by landslide along Route 17 in Kawaguchi (37.291N, 138.836E).

Fig. 7. View of railroad tracks displaced by landslide along Route 17 in Kawaguchi (37.291N, 138.836E)

Fig. 8. View of head scarp of landslide along Route 17 in Kawaguchi (37.291N, 138.836E).

Fig. 9. Damage to overpasses of the Kan-Etsu Expressway in Ojiya. Embankments between overpasses slumped (note sheet piles to support new roadway) and pulled apart concrete box culverts. (37.314N, 138.779E)

Fig. 10. Separated concrete joint in highway overpass. Approximately 60 cm of displacement observed. Similar deformation patterns and displacements observed at several overpasses. (37.314N, 138.779E)

Fig. 11. Close-up view of concrete joint separation. (37.314N, 138.779E)

Fig. 12. Another view of concrete joint separation. Marks on the wall indicate a drop of both side of the overpass (37.314N, 138.779E)

Fig. 13. Damage to roadway beneath overpass due to movement of concrete box culverts. (37.314N, 138.779E)

Fig. 14. Photograph of roadway, looking east towards the Shinano River, after it passes under the Kan-Etsu Expressway. Roadway is damaged at intersection, and additional cracks were observed further down the roadway. This cracking may indicate some global spreading, as well as localized failures of expressway embankments. (37.314N, 138.779E)

Fig. 15. Another damaged road after it exits from expressway underpass. (37.314N, 138.779E)

Fig. 16. Lateral displacement of road adjacent to Kan-Etsu Highway embankment. (37.314N, 138.779E)

Fig. 17. Underground storage tank that floated out of ground due to buoyancy during liquefaction of poorly compacted fill. (37.313N, 138.780E)

Fig. 18. Floating manholes in Ojiya due to poorly compacted backfill.