The sediment drainage efficiency of a sand sluice gate in the motionless state bedload

Abstract

The sand sluice gate opening levels is an important problem for sand deposition drainage with the appropriate flow rate. This research proposes the determination of sand drainage efficiency by opening the sand sluice gate at different levels in the motionless state of bedload. The sand draining efficiency was determined from an experiment in an Ogee weir physical model with one sand sluice gate, 0.18 x 0.18 m2 in width and height. The experimental sand deposition depth was set at 22%, 33%, 66%, and 100% of the sand sluice gate height. For water drainage purposes, the sand sluice gate was opened at 20%-100% of the sand sluice gate height. The experimental sand-size sediment is 0.85-2.00 mm., D50 is 1.5 mm sand-size. The data obtained from the experiment consisted of the maximum erosion distance from the sand sluice gate, the maximum side erosion distance of the sand sluice gate, and the sand drained volume. The experiment results show that the sand sluice gate opening level from 60% to 100% provides the maximum side erosion distance, and the longest erosion distances from the sluice gate were 1 and 2 times the sluice gate width, respectively. The sand deposition from 22% to 100% of sand sluice gate height was drained about 3%-34% of total sand deposition volume. The best sand sluice gate opened value is 60% sand sluice gate height which provided the volume of sand drained is nearly 80% and 100% sand sluice gate opened. Therefore, the gate opened at 60% sand sluice gate height provides much sediment drained while reserving more water for the dry season.