Author(s): Tatsuhiko Uchida; Shoji Fukuoka

Linked Author(s): Tatsuhiko Uchida, Shoji Fukuoka

Keywords: Bed protective work; Threshold of block movement; Hydrodynamic force; Deformation and failure mechanism; Last row elements; Vertical two-dimensional model

Abstract: Bed protective works are installed on the bed downstream of a weir to prevent failure and collapse of the structure due to bed scouring. Because failures of bed protective works expose the main structure in danger, it is important for river technology and management to maintain the safety of the bed protective works. So, it is required to establish the method for evaluating the hydrodynamic forces acting on the bed protective blocks and estimating the deformation range of the structure. In this paper, we measure the hydrodynamic forces acting on the last row elements in the threshold of block movement and developed the threshold model of block movement. The model of a vertical two-dimensional analysis for the flow with complex boundary shape of the blocks is presented, in order to evaluate hydrodynamic forces acting on the blocks. Then, we developed the numerical model for deformation of the bed protective works downstream of a weir using the threshold model. It is clarified through the comparison between measured and computed results that the model can explain the experimental deformation process.

DOI:

Year: 2005