The Optimization Designing Of Small Watershed Cascade Dam In Hilly Areas

Small watershed cascade dam is a project form for soil and water conservation and rainwater utilization in hilly areas. After several decades of practice we have accumulated some experience and obtained better economic and social benefits, but there is still no well mature theory in planning and design of small watershed cascade dam system, which regard irrigation as main goal. With the purpose of accelerating its construction and development and constructing economic, high-efficient, stable and concordant small watershed, it is urgent to study on the planning and design methods of small watershed cascade dam system.By unified application of the theories about water and soil conservation, engineering economy and system analysis, this paper systematically studies on the optimization planning of cascade dam system and optimization design of single dam. The main contents include: (1) It generalizes the channel of small watershed , and establishes the relation of dam height and drainage area, building charge and dam height, benefit and drainage area and so on; (2)Regarding the converging water of each level dam and dam height as decision variables, it establishes a small watershed dam system optimization programming mathematics model ,and introduces the model solution algorithm by LINGO software;(3) For simplifying the slope design of earth dam in cascade dam system and improve the calculating efficiency, this paper applies LiZheng software and Origin software to simulate and establishes the table curves of searching and calculating slope coefficient are established in each condition; (4) It establishes a nonlinear programming mathematics model for optimization design of spillway water -crossing section ,and the optimal results can be obtained by using grid method; (5)It establishes a grey relation projection model of selecting the slope type of earth dam; (6)It develops an optimization design software of single dam (small earth dam) in small watershed dam system by Delphi;(7)Taking Xuyi dou Hill small watershed as an example, the optimization planning of a dam system and optimization design of single dam are done to this area , which validates the scientificity and practicability of the research results in this paper. This paper studies the optimization planning method of cascade dam system and optimization design method of single dam in small watershed systematically, greatly abundances the planning and design theory of small watershed cascade dam system, and has obvious theoretical value and practical significance.