Weir removal and its influence on hydro-morphological features of upstream channel

Abstract

This paper presents an experimental study on the upstream channel responses due to partial removal of a weir, focusing on the impacts of the removal shape of the weir on the hydro-morphological features. It is found that the shape of the removal significantly affects the 3D flow structure and the local scour around the weir and poses influences on the propagation process of upstream sandbars. However, the characteristics of the sandbar system at the quasi-equilibrium stage are governed by the removal area rather than the removal shape. Governing parameters characterizing the removal shape is proposed as well. Desirable morphological features could be achieved by a careful selection of those parameters.