EXPERIMENTAL AND FIELD STUDY ON EROSION PROCESSES OF PLACED SEDIMENT AT THE DOWNSTREAM OF DAMS

Abstract

Recently, excavated or dredged sediment is often conveyed and placed to the downstream of dam site for the purpose of recovering river environment and solving sedimentation problem in reservoirs. To make appropriate sediment supply in consideration of the river environment, there is a need for a method to plan a volume, a shape of placed sediment. Additionally, it is also required to develop a prediction method to estimate the erosion process. In the study, laboratory experiments and three field observations were conducted to clarify the erosion process of placed sediment. As a result, relationships between hydraulic conditions and the erosion process of placed sediment were recognized.