Figure B.12. Comparison of Cppm measured and Cppm computed using Laursen and
modified Laursen equations for silt-bed rivers.
Table B.15. Discrepancy Ratio RD Between Computed Cppm and Measured Cppm for
Silt-Bed Rivers.
Laursen
Modified Laursen
Discrepancy Ratio RD
1.45
0.991
medium to very
coarse sand-bed
gravel-bed
silt-bed
very fine to fine
sand-bed
Figure B.13. Relationships between V*/ωi and logf(V*/ωi) for river size.
B.5 RANGE OF DATA FOR VALIDATION
To validate the Kodoatie et al. power relationship and modified Laursen equation, data from
Group 2 were used. The computed Cppm from the proposed methods were compared to the
measured Cppm. Note that because sets of data for gravel-bed rivers were relatively small,
the laboratory data of Meyer-Peter and Mller (1948) containing 139 sets of data were used
B.28