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Chapter 5 - Test results
5.3 Main tests
The main tests were performed during one year from February 2000 to February 2001. The tests
followed the general test procedure described in section 4.5. For all the tests a complete set of
measurements was recorded including the water surface, the bed topography, the velocities, the
evolution of the water and bed topography on the outer side wall, the grain size distribution of the
armoring layer after the test, the discharge and the bedload transport rate.
5.3.1 Description of the Appendixes
The test results are summarized in the different Appendixes at the end of the present report. Most
representations are based on the same structure with 3 rows and 4 columns. In general, the rows
are the different discharges (150, 180 and 210 l/s) and the columns represent the different spacings
of the macro-roughness (no macro-roughness, rib-spacing every 4°, 2° and 1°). The tests are
presented from the lowest (Appendix *.1) 1 to the highest channel bed slope (Appendix *.3) for
the ribs of 20 mm depth and finally for a bed slope of 0.50% with deeper ribs (40 mm)
(Appendix *.4). Special phenomenon and measurements are usually documented in Appendix *.5.
• Appendix 1 summarizes all test parameters and results including the tests of PETER (1986).
• Appendix 2 gives tables, schemes and informations relative to the data acquisition, the
acquisition devices and the data treatment. Furthermore sample protocols and observations
made during the test can be found in this section.
• Appendix 3 shows situation plots, longitudinal bed profiles and comparisons between initial
and final bed topography for the preliminary tests (see also § 5.2).
• Appendix 4 gives the measured final bed topography compared to the initial one (recorded
after the armoring at a discharge of 70 l/s). The isolevels correspond to an elevation difference
of 20 mm. The data points for the plots (a grid of 50 x 50 mm with an absolute reference
relative to the bend) were interpolated linearly between the measured data points (grid
of 90 x 90 mm with a reference relative to the measurement frame). Positive bed elevations
correspond to depositions and negative values to erosion.
The last section (4.5) compares the results of a long term test with a “normal” duration. The
final bed topographies after 13 and 27 hours are compared.
• Appendix 5 shows the final water surface compared to a horizontal average surface over the
whole channel (average of all data points). The isosurfaces correspond to a distance of
10 mm. The resolution of the data points is the same as for Appendix 4.
• Appendix 6 presents systematic pictures of the water surface in the bend between 10° and
90° taken in the downstream direction.
• Appendix 7 gives the water and bed levels in selected cross-sections every 15° from 1 m
upstream the bend to 1 m downstream the bend. The plots further indicate the mean water
and bed levels (average over the cross-section) and the initial bed level. The vertical axis of
1. * is used as a placeholder for the number of the different Appendixes.
page 108 / November 9, 2002
Wall roughness effects on flow and scouring