2:15 PM - 2:30 PM
[HDS15-03] Liquefaction risk evaluation using relative height data of natural levee
Keywords:liquefaction hazard map, natural levee, relative height
In this study, land condition map, 5m grid DEM and liquefaction occurrence area by The 2011 off the Pacific coast of Tohoku Earthquake in downstream of the Tone River were overlaid by GIS. The relative height of natural levee was calculated from an elevation of the natural levee liquefaction generated and an elevation of other neighbor landform such as back marsh, coastal plain and delta.
After the liquefaction occurrence rate of the natural levee was calculated every relative height difference of the 0.5m unit, the liquefaction occurrence rate decreased suddenly between 1.5 m-2.5 m of relative height or the liquefaction occurrence rate gradually decreased over 1.5 m-2.5m of relative height. It is appropriate to establish a border of relative elevation of a natural levee by 2m or 3m.