Optimization Study For Districting Dam Based On Fluid-Structure Coupling Analysis

Embankment dam is one of the important dam types in dam engineering. It has advantages as follows: obtaining raw material locally, simple construction, short construction period, low cost, saving a large number of cement and steel, strong adaptability in poor geological conditions and good safety performance, it widely used at home and abroad. At present, the design of embankment dam is mostly based on the traditional design method, and its optimization design is still in the experience stage, and the design theory is also in the process of further maturation.In order to explore the optimum material subarea scheme and the section size of embankment dam, a plan is proposed by building different subareas and dam material configuration schemes, as well as analyzing fluid-structure coupling and slope stability by ANSYS of each scheme, which is based on the orthogonal experiment design theory, Through analyzing the experiment results, the dam material configuration rule is discussed. According to this rule, the optimal partition scheme is obtained, and optimum design of dam section size of the scheme is carried out, under the premise of meeting the requirements of dam safety and structural design, the final optimization scheme which can give full play to the role of dam materials and save the project cost is obtained, main contents of this paper are as follows:(1)To establish embankment dam of two-dimensional finite element model by ANSYS, and compile corresponding APDL command stream, the two-dimensional seepage-stress coupled field analysis is carried out. Based on the coupled field analysis, dam slope stability of two-dimensional embankment dam is analyzed by strength reduction FEM to obtain the seepage flow, overflow point position and slope stability factor of embankment dam modal, and it provide the data base for the subsequent optimization process.(2) In terms of an embankment dam engineering, considering the dam body subarea and each district adopting the same or different dam material, by using the orthogonal experiment, different partition and dam material allocation scheme are designed. Two-dimensional seepage and stress field coupling and slope stability is analyzed for each scheme, through the analysis of the results the scheme which can meet the dam stress and displacement requirements, ensure the requirement of seepage stability, as well as save the engineering cost, thus to achieve the purpose of economic security and rational allocation of each partition.(3) Section optimization design of embankment dam is based on the result of partition optimization and section preliminary design scheme, according to the requirements of specification and a particular target that the structural features and the stress state of earth embankment dam, optimization model is established, based on structural analysis, the optimization of the above section can be applied to the ANSYS optimization module, so as to explore the optimal dam structure size, establish mathematical model of structural optimization design and then the safe, reliable, and reasonable economic section form is searched out automatically from a series of possible scenarios. It is good for saving talents and improving the design level.The results show that both sides of the dam body and dam bottom configure high strength materials, center of the dam configures the materials that have good performance in anti-seepage, the region near downstream configures the materials that have good infiltration capacity. Compared with the traditional dam type, this optimization subarea scheme plays a role of dam material seepage and slope stability more fully. The methods overcome the shortcomings that the previous material subarea was given mostly according to designer’s experience, it provides new ideas on the future design of embankment dams.