Seite - 536 - in Book of Full Papers - Symposium Hydro Engineering

In the high flow period, the composition ratio of sand was about twice that of the low flow rate due to the high velocity. Table 2. Inflow Suspended Sediment Composition Suspended sediment composition (%) Clay Silt Sand High flow season(May ~ Aug) 32 52 16 Low flow season(Sep ~ Apr) 21 46 33 Fig 2. Suspended Sediment Rating Curve It was difficult to predict the exact inflow bedload amount due to the lack of observation data. So the bedload was assumed to be about 10% of the suspended sediment. The total amount of sediment flowing into weir was calculated by summing up the bedload and suspended sediment. The amount of sediment was estimated to be 4.4Mt considering the discharge condition during the year. 2.3. SEDIMENT MANAGEMENT GOALS When the sediments flow in the weir, they have a strong influence on the operation, maintenance, and economics of the hydropower project. Therefore, we set a sediment management goal of preventing 0.2mm or higher of sediments from flowing into the intake. 3. SAND TRAP DESIGN 536