流砂捕捉ポンプの開発と性能評価

抄録

A new pumping sampler was developed for collecting relatively large sand suspended near the river bed. This lift pump is composed of vacume pump, compressor for airlift, air-liquid separator and screen. The laboratory experiments showed that a particle the size of 5mm is lifted up to 20m high and is transported up to a distance of 120m. The size distribution will change at the intake, however it is possible to calibrate the measurement distribution by using experimental relationship between concentration change, particle size and transport distance. The field experiments showed that the suspended sand concentration increase near the bed and the vertical distribution are in approximate agreement with theoretical curve.