Experimental Study on Flow Characteristics of Driftwood and Accumulation Condition of Driftwood at Bridge
長谷川, 祐治 ,
中谷, 加奈 ,
竹林, 洋史 ,
里深, 好文藤田, 正治
京都大学防災研究所年報. B = Disaster Prevention Research Institute Annuals. B
357 , 2015-06 , 京都大学防災研究所
In recent years, large-scale sediment disasters occur frequently due to extreme weather. Not only sediment but also driftwoods cause expansion of damage in sediment disasters. In particular, there are some cases that flooding occurs from the point of bridges where driftwood integrated. Therefore, for future disaster prevention planning, it is important to know the conditions of driftwoods integrated on bridges, and the characteristic of the driftwood flowing down. In this study, we have conducted experimental study and organized the basic data of driftwood characteristic in Fr>1, super critical flow condition, especially on accumulation. From this study, we concluded that critical conditions for driftwood integration on bridges have correlation between supplied driftwood volume and combined value from following parameters; length of driftwood, driftwood diameter, flow depth, river width, clearance of the bridge, and the slope.