Grain‐Size Distribution of River‐Bed Armor Layers

Abstract

There appears to be both experimental and theoretical support for the selection of a normal curve for the description of the armor-layer grain size distribution. The findings of this study indicate that if a sufficiently wide range of grain sizes is available in the bed-sediment material, the normal curve will be similar to that describing the statistical variation of the bed-shear stress, and its parameters (mean and standard deviation) will not depend on the original bed-material size distribution. However, it should be stressed that this conclusion is only tentative, as there obviously is a need for more research in this area, in particular with regard to the sampling procedure for armor layers.