Erodibility of fine soil from the composite river bank of Brahmaputra in India

摘要

The erosion of a composite river bank critically depends on the erodibility of its fine soils, as the fine soil has higher resistancenagainst erosion. Therefore, for the estimation of the bank erosion in the case of a composite river bank, it is important tondetermine the critical shear stress and erodibility coefficients of the bank soil and their spatial distribution. In the present study,nerodibility parameters of the river bank of Brahmaputra in India have been estimated through 58 in situ submerged jet tests.nThe significance of spatial and layer-wise distribution of the erodibility parameters was tested through analysis of variancen(ANOVA). Results indicate that the spatial variation of erodibility parameters is highly significant, but layer-wise variationsnof the erodibility parameters are not significant. Therefore, the erodibility of the riverbank depends on the particular location,nwhereas layer-wise average erodibility parameters can be lumped for the estimation of the bank erosion for the specific site.nUsing the measured erodibility parameters, yearly river bank erosions at the study locations were computed and found to fallnwithin the reported range of the bank erosion in the Brahmaputra River. Copyright  2010 John Wiley & Sons, Ltd.