TY  - JOUR
A1  - Auel, C.
A1  - Boes, R.M.
A1  - Sumi, T.
T1  - Abrasion prediction at Asahi sediment bypass tunnel based on Ishibashi’s formula
JF  - Journal of Applied Water Engineering and Research
N2  - Abrasion in a concrete-lined sediment bypass tunnel is estimated using a Japanese state-of-the-art prediction model and validated by measured invert abrasion data at Asahi Reservoir, Japan. The model is described in detail, certain shortcomings are disclosed, and a revised version is proposed. The model consists of a kinetic energy term accounting for the impact by saltating particles, and a friction work term accounting for the grinding stress. It is found that the latter term yields concrete abrasion values being consistently a multiple compared to its kinetic term contradicting other research. Based on that, and a possible particle impact angle inconsistency, it is proposed to omit the friction work term. It is shown that the calculated abrasion is overestimated by 138% on average compared with that measured, if both terms are accounted for. However, promising results are obtained with only 30% overestimation by neglecting the friction work term.
Y1  - 2018
U6  - http://dx.doi.org/10.1080/23249676.2016.1265470
SP  - 125
EP  - 138
ER  - 
TY  - JOUR
A1  - Koshiba, T.
A1  - Auel, C.
A1  - Tsutsumi, D.
A1  - Kantoush, S.A.
A1  - Sumi, T.
T1  - Application of an impact plate - bedload transport measuring system for high-speed flows
JF  - International Journal of Sediment Research
N2  - To achieve the sustainable use of dams, the development of methods for sediment management in reservoirs is required. One such method includes the use of Sediment Bypass Tunnels (SBTs) to divert sediment around a dam, thereby preventing sedimentation in the reservoir. However, SBTs are prone to severe invert abrasion caused by the high sediment flux. Therefore, it is necessary to establish a measurement system of the sediment transport rate in these tunnels. One system to measure sediment transport in rivers is the Swiss plate geophone, which can register plate vibrations caused by particle impact. In Japan, the Japanese pipe microphone is used, and sediment transport is measured based on the sound emitted by the particle impact. In this study an attempt was made to optimize the advantages of both systems by fixing a microphone and an acceleration sensor to a steel plate. The results of calibration experiments with this new system are presented and compared with the existing methods. It was found that the acceleration sensor can detect sediment particles larger than 2 mm in diameter. Moreover, a new parameter, referred to as the detection rate, was introduced to describe the correlation between the actual amount of sediment and the registered output. Finally, two parameters - the saturation rate and hit rate - are introduced and exhibit strong correlation with the detection rate.
Y1  - 2018
U6  - http://dx.doi.org/10.1016/j.ijsrc.2017.12.003
SP  - 35
EP  - 46
ER  -