Caluculation of Ice Cover Roughness from Velocity Distributions

Abstract

Field measurements of velocity profiles for ice-covered streams were performed in Hokkaido. Surface conditions of the cover were classified into smooth ice cover, rippled ice cover and cover with frazil slush. Adaptability of logarithmic velocity distribution was first investigated. The friction factor fi and Manning's roughness coefficient ni were caluculated based on an assumption of the logarithmic distribution; average values ni for smooth and rippled cover were 0.012 and 0.021 respectively.