Abstract
In this research, a series of laboratory experiments were carried out to estimate
the removing sediment amount from upstream weirs using bottom outlets. The
experiments were conducted in a laboratory channel (24.6 m) in length and (0.81 m)
wide, in middle of which a weir was fixed. Six discharges were allowed to flow with,
three different sediment concentration for each. The results showed that there is a direct
relation between the area of the holes, Froude number and the amount of sediment
removed, the depth of aggradation near weir location decreases with increasing the
number of holes. A dimensionless equation was created to compute the amount of
sediment removed in terms of area of the holes with a coefficient of determination
(0.895) and the percentage of the highest and lowest difference between the measured
and calculated sediment amount were (15.7, 0.2), respectively.
