Author(s): Masahiro Hashiba, Atsuhiro Yorozuya, Hiroshi Koseki and Koichi Tsuchida
Linked Author(s):
Keywords: Field measurement; MBES, ADCP; Bed form migration; Bedload discharge
Abstract:
In this study, the authors conducted the multipoint measurement of riverbed by MBES and the bedload velocity by ADCP mounted on a maned-control boat during snow melting flood in Ishikari River. At the 2 section of about 40 m in a longitudinal direction, we measured bedform repeatedly in order to monitor the movement of the waves. In addition to that bed materials were sampled at 12 points by the Kumada Dredge sampler. Based on the observed results, the followings aspects were obtained. 1) Sand wave were measured which is the height/length of 0.07 m. 2) The moving speed of sand wave analyzed using the space-time image velocimetry (STIV) method. 3) Observed the sand wave and the bed shear stress showed good agreement with the curve constructed by Yalin (1978). 4)Regarding the bed load discharge, two different methods were compared. First one is the bed form migration, which is the function of the wave height and the wave speed proposed by Kikkawa et al. (1985). And second one is the method using ADCP proposed by Koseki et al (2016). Those two results show good agreement.
Year: 2019