Bedload measurement by acoustic energy with Hydrophone for high sediment
transport rate
Takahisa MIZUYAMA, Miwa MATSUOKA and Michinobu NONAKA
Abstract
Hydrophone has been used to measure bedload transport intensity by counting the
number of pulses made by hitting of sand and gravels to a steel pipe. When sediment
transport rate is high, the sound level is continuously high and never drops low
resulting in that the number of counting becomes low or zero. Sound level is recorded
to know sediment transport intensity instead of pulses when sediment transport
rate is high. The method was adopted in the Waru]dani torrent, a branch of the
Jinzu River. The relationship between acoustic energy and pulses were analyzed.
The acoustic energy was well recorded and showed sediment transport intensity
as well as the record of pulses. It was found that there is an appropriate amplification.
As we have not obtained good data for high sediment transport rate, we will continue
the measurement.