Technical Studies

The purpose of this study is to examine the regulation planning rules for hyperconcentrated river through understanding the transport behavior by means of parametric analysis, numerical simulation, and physical modeling. This study will be accomplished in three years. The result from theoretical analysis and scenarios application is expected to provide engineers a guideline for their planning and design needs.

The study surveyed the causes of hyperconcentration flow (HF) and related theorem, and reviewed the development of numerical modeling, physical modeling, and related studies, based on the outcome, the definition of HF for the study is proposed. Besides, the patterns of the HF hazards occurred in Taiwan are also summarized. To quantify the rule for planning and design, a 2-D depth-averaged HF model is developed. By following the numerical experiment results a few concise quantified parameters are presented. During the model development, the physical modeling for fixed and movable bed are conduced to verify the numerical modeling. The capability of the numerical model consists of the effect of density variation, Bingham fluid simulation, and the sediment transport simulation. The study proposed the increments of depth, shear stress and velocity under the condition of HF, as the quantified parameters for planning and design. Then, a standard framework of planning and design procedure is proposed as a technical guildine for engineers. In the end, the Tung-Pu-Rey creek is studied by following the procedure proposed. The HF concise handbook was edit, and the computer aided operation system consisting of the procedure and the application study, was established to assist engineers to perform the planning and design for HF reaches.