Research On The Stability And Optimal Design Of High Concrete Dam In Tailing Reservoir

Presently, perviousrockfill dam has been widowever, it is not stable enough since ielt tyuensedds toin ddaesign of tailing reservoir as initialdam. Hmage in the form of “drumbelly”,etc., due to overtopping. Comparing with it, concrete dam has its unique advantage asit can generate only a whole slip and won’t crush itself due to piping.Combining with Baishizhang molybdenum#3tailing project in Mei Zhou city, GuangdongProvince, this thesis studied earth pressure, stress and stability of the high concrete dam.By calculating the earth pressure behind dam, this essay compared and analyzed the existinganalytical methods of calculating earth pressure. The calculation results showed that, staticearth pressure> Rankine active earth pressure>“standard method” active earth pressure>Coulomb active earth pressure>“energy method” active earth pressure. The results calculatedby the later3methods were very close, within1%. When earth-fill surface inclined, staticearth pressure and Rankine active earth pressure parallel to the direction of filled soil surface,while the angle of active earth pressures calculated by coulomb theory, the energy method andstandard method to wall back is δ.In order to study whether soil pressure can be reduced by setting a soft zone between dam andsoil, the finite element method was used. The results indicate that: the soft zone can increasehorizontal displacement, produce a plastic zone, form the approximate active earth pressureconditions and reduce earth pressure. Specifically, earth pressure reduced about17%compared with static earth pressure, when the soft zone was5m in width with E=5000kPa.By analyzing stability, stress, and optimal designof initial dam, it is described that: a. themaximum principal stress (tensile stress) occurred around dam heel, and minimum principalstress (compressive stress) generated at dam toe;b. the tensile stress area near dam heelexpanded with soil pressure and downstream slope.From the respect of cost, construction period, dam temperature control measures andanti-permeability performance etc., this paper expounded the characteristics of buried stoneconcrete dam and the RCC dam. Based on that, this thesis investigated the feasibility ofconstructing the initial dam adopting the above two materials. The results show that: a. buried stone concrete dams can decrease the cost at approximately40%, speed up the constructionprogress (around30%), simplify the temperature control measures, but when constructionquality control easily tested; b. The RCC dams could reduce the total investment at about15%~30%, shorten the construction period around30%~50%, and greatly simplify temperaturecontrol measures. But there are weak leakage faces which deserve good anti-seepageprevention.