2008 Volume 2008 Issue 258 Pages 501-506,a1
We measured the coefficient of roughness in a hydraulic experiment using a concrete channel whose surface was treated to simulate abraded concrete. Various surface roughness parameters were trialed to determine those that best represent the surface roughness of the experimental concrete panels. The calculated coefficient of roughness (n) was 0.013. This value is within the range of the design standards for concrete channels. The height distribution of the surface of the experimental channel was characterized by skewness that showed bias of the height distribution of the roughness. The equivalent roughness of the simulated abraded concrete channel can be expressed as ks = 2 × Ra for Ra of 0.5 ± 0.12 mm or ks = 0.26 × Rz for Rz of 4 ± 1.43 mm.