Research Journal of Environmental Sciences1819-34122151-8238Academic Journals Inc.10.3923/rjes.2009.71.79ArmanA. Fathi-MoghadamM. SamadiH. EmamgholizadehS. 1200931In order to characterize the settling properties of
natural cohesive sediment adjacent to the Dez Dam wall (as a symbol of
a large dam reservoir in arid and semi-arid zones), falling velocity of
particles have been measured using a 2.50 m height and 0.30 m diameter
column. In contrast to the traditional particle size based methods, an
approach relying on time and depth variation of sediment concentration
was employed to estimate the mean value of fall velocity at any depth
and time. Particles in deeper depth, particularly for the samples with
higher rate of sediment concentration accelerated faster and stayed at
higher velocities for longer duration as a result of higher rate of flocculation.
This confirms the greater effect of particle flocculation than their settling
competition. The particles in all depths reached their maximum falling
velocity same time around 15 min after the beginning of the tests. The
low concentration samples reached higher maximum velocity as a result
of lower rate of particle compaction but for a much lower duration in
comparison to the higher concentrated samples.]]>Annandale, G.W., 20051st Edn.,Fan, J. and G.L. Morris,1992118370384Fathi-Moghadam, M., P.H. Torbi, M. Ghomeshi and M. Shafaei,2008136368Fathi-Moghadam, M., A. Arman and B.H. Samadi,20072007Pages: 360Hamm, L. and C. Migniot,19941994pp: 93-106pp: 93-106Kranenburg, C.,19981916651680Krishnappan, B.G.,2000In situ size distribution of suspended particles the fraser river.]]>126561569Krishnappan, B.G. and J. Marsalek,20023638493859Krone, R.R.,19631963Liu, J., B. Liu and K. Ashida,20022002pp: 110Mehta, A.J., T.M. Parchure, J.G. Dixit and R. Ariathurai, 19821982pp: 591-609pp: 591-609Mehta, A.J.,19931993pp: 577-584pp: 577-584Morris, G.L. and J. Fan,19971st Edn.,Pages: 3Pages: 3Samadi-Boroujeni H Fathi-Moghaddam, M., M. Shafaie and H. Samani,20051st Edn.,Samadi, H. and V.J. Galay,20052005pp: 127127Simons, D.B. and F. Senturk,19921st Edn.,Pages: 463Pages: 463Toniolo, H. and G. Parker,20032003pp: 457468Winterwerp, J.C.,20022213391360White W.R.,20002000