ABSTRACT
Present study discussed the flow resistance in an actual river with river-bed change during flooding using observed data and tried to confirm the validity of an equation expressing the relation among the dimensionless total share stress https://www.w3.org/1998/Math/MathML"> τ * https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1266.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> , dimensionless shear stress due to grain roughness https://www.w3.org/1998/Math/MathML"> τ * ' https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1267.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> and dimensionless shear stress due to form resistance https://www.w3.org/1998/Math/MathML"> τ * ' ' https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1268.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> . To calculate https://www.w3.org/1998/Math/MathML"> τ * ' ' https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1269.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> directly, two monitoring points for river-bed elevation change were set in the longitudinal direction of the river and wave length was estimated from those 2 data of river-bed change. By comparison of 2 types of https://www.w3.org/1998/Math/MathML"> τ * ' ' https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1270.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> , one is calculated directly and the other is estimated from the observed https://www.w3.org/1998/Math/MathML"> τ * , τ * ' https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1271.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> , it is shown that the relation https://www.w3.org/1998/Math/MathML"> τ * = τ * ' + τ * ' ' https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429069246/b59e18fc-9e1d-4389-b000-a1069c1cd27e/content/eq1272.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> is correct in the actual river and Manning’s n can be estimated if the shape of sand wave can be estimated.
