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The many advantages of earth dam because of its near to, local materials, construction convenient, short construction period, low cost, and can adapt to poor terrain, geological and climatic conditions, good safety performance is widely built. Core rockfill dam embankment dam is a very important type of dam, its structure can be divided into the main rockfill zone, secondary rockfill zone, buffer layer, a filter layer, and impervious core wall. District dam material properties vary considerably reduce the project cost, full use of the spoil. If the dam material partition configuration unreasonable, will not only affect the safety of the dam will increase the dam construction costs, meet structural requirements as well as dam safety, how reasonable partition configuration to achieve the dam materials to save cost The purpose of the core dam design an important issue. Them in the design and construction of embankment dams, not only on the embankment dam dam material performance study of the district, such as the strength of the stockyard various filling material, compaction, seepage performance; need various dam profile partitioning scheme than the election law of stress and deformation analysis of each partitioning scheme. In addition, in order to take full advantage of the soil, stone near the dam site, the need to stress and deformation of the dam material parameter sensitivity analysis, study dam sectional partition and material parameters change dam stress, deformation, arching effect and anti-hydraulic fracturing ability to finalize the selection of what materials as damming material to provide a very important reference value. In this paper, earth core rockfill dam, for example, E-ν model introduced and used several soil constitutive model Duncan - Duncan - EB model, generalized Duncan - Chang EB model and D? P model, ultimately selected Duncan - EB model this enough as the stress and strain analysis model nonlinear elastic model; and use of the geotechnical software GEOSTUDIO SIGMA / W module prepared by four different profiles dam material partitioning scheme completion and impoundment period and five sets of original material parameters, respectively, the the plane nonlinear finite element analysis. In addition, the secondary rockfill zone on the basis of the reference parameters, by changing the material parameters, analyzed dam stress and deformation characteristics of the various programs and material parameters on the dam stress strain sensitivity analysis, summarized summarizes the different partitions of the material as well as some of the material parameters of change of the stress and strain of the dam. Finally, verify the dam slope stability of each partitioning scheme. Through comparative computational analysis, the following conclusions can be drawn: in the the intended dam partition and material parameters indicators of stress and deformation of the dam to meet the design requirements, dam partition and material configuration is reasonable. Although the dam profile partition and material parameters change would have some impact on the stress and deformation of dam, dam stress, deformation, heart wall arch effect as well as resistance to certain differences in the size of the hydraulic fracturing capacity, but has little effect . In contrast, in the same kind of material, corresponding to the partition scheme P1 dam deformation minimum arching effect is strongest; P4 deformation arching effect weakest. The same partition minimal deformation of materials program M1, M4 arching effect most strongly; M2 deformation, M5 arching effect the weakest. Four kinds of partitioning schemes the dam slope are safe. Overall, the various dam profile material partition advantages and disadvantages, and the need to consider the impact of various factors, and choose the best program in the design and construction.
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