音更川における澪筋部の蛇行形状の発達と河岸侵食評価

抄録

Stream way of the Otofuke river had been changed drastically during the flood in September 2011. Though the peak discharge of the flood was not so high compare to the peak discharge of the Otofuke river plan, bank erosion has been occured several places. Further a part of dike of KP18.2 has flowed out. Therefore, the countermeasure of dike protection is needed in the Otofuke river. In this study, a evaluation method of dike break has been investigated using Nays2D which can consider bank erosion as slope failure model. Calculation using Nays2D has been tested by applying to the flood at September 2011. The features of the flow and bed evolution during the flood can be confirmed by the calculation results. Also dangerous point for dike break can be evaluated using the deepest bed movement in each cross-section. Using those results dangerous point at next flood has been evaluated.