76
R.H. Charlier and Chr. P. De Meyer
w, = 7~'~[[1+ °'°l@- l)¢a~'~, )~- ~j^" .]
ds =
+ o.o,
- 1>(w "]2
tu*,o)
2 t,,dso
%,o~=(Ps - 9) g dso 0o~,
(-%r = 0.24 D, lif 1 < D. < 4
@)or = 0.14 D*-°'64if 4 < O. <_ 10
~-)cr = 0.04 D *l if 10 < D. < 20
(gcr = 0.013 D *°z9
®cr = 0.055
pg ( u'~ 2
U.,c ~
U
C
C,=181og(12d)
~.3d9o J
C = 18log[ 12d)
tic=)
= particle fall velocity
=- representative particle
(size of suspended sediment,
d5- dso for T>25)
= ratio of sediment and fluid
mixing coefficient (J3m~=2)
(m/s)
(m)
(-)
= gradation co~ffici6nt of bed
material
(-)
= critical bedshear stress
according to Shields
(N/m 2)
Shields curve
if20 < D. < 150
ifl < D. < 150
= current-related effective
bedshear stress
(9
(N/m 2)
= current-related overall bedshear velocity
= grain-related Ch6zy
coefficient
(m/s)
(m/s)
= overall Ch6zy coefficient
(~s)