Application of a roughness identification model to assess the variation of roughness coefficient of the Duong river in flood season

Abstract

For alluvial rivers, the variation of the roughness coefficient could be attributed to the variation in bedforms and the higher energy and momentum losses for picking up and transporting the sediment of high flows. The effects of these factors on the roughness coefficient are usually needed to measure directly velocity/flow or conduct experiments. These methods are expensive and time consuming. In this study, a roughness identification model was applied to investigate of the variation of the roughness coefficient with time in the Duong River for different flood events in different years. The results show the consistent and general trend of the variation of roughness coefficient of the river in the flood season. The study indicated that this method can be used as a means to assess the variation of the roughness coefficient with time for rivers.