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Feng F.,China Institute of Water Resources and Hydropower Research | Zhang G.,China Institute of Water Resources and Hydropower Research | Guan J.,North University of China | Zhang C.,Power Construction Corporation of China | Wang W.,North University of China
Yingyong Jichu yu Gongcheng Kexue Xuebao/Journal of Basic Science and Engineering | Year: 2016

Based on the analysis of particular surface crack found in upstream water stop area of super-high arch dams during construction, grouting grove and pipeline between two upstream copper water stops, and that between copper water stop and grout stop, were proposed to be cancelled, that is to optimize the grouting layout design. Under the guidance of this optimized design, impact on working performance of non-grouted transverse joints in upstream water stop area of super-high arch dam, was studied with the help of the software of multi-field simulation and nonlinear analysis of complex structures. The results show: Significant effect is shown on the local stress at both sides of upstream transverse joints, however, it has little effect on the deformation and stress state of whole structure, verifying the rationality and feasibility of this construction recommendation. © 2016, The Editorial Board of Journal of Basic Science and Engineering. All right reserved.

Zhang C.,Power Construction Corporation of China | Hu Z.,Wuhan University
Shuikexue Jinzhan/Advances in Water Science | Year: 2014

In this paper, a mathematical model is designed to estimate the water containment risk for high rock-fill dams during interim seasonal flooding based on the condition that the water must not flow over the top of the dam, and other stochastic factors such as the level of the floodwater in front of the dam and the high water level during flooding. The characteristics of rock-fill dam construction systems, the number of days each month when the dam is under maintenance, and the stochasticity of the average speed of the increase in water level per day are considered for designing a model to calculate the simulated height for flood prevention during interim flooding. Based on the Monte Carlo method, the created risk model is solved by linking stochastic elements from hydrology, hydropower, and construction. Further, the influence of the controllable construction indicator, which is the minimum average daily rising speed, on the risk rate is researched. The feasibility and effectiveness of the risk model and the calculation method are demonstrated through the analysis of Changheba hydropower station in the Dadu River basin in Sichuan, China. ©, 2014, China Water Power Press. All right reserved.

Liu Y.,Beijing Jiaotong University | Diao S.-M.,Beijing Jiaotong University | Diao S.-M.,Applied Technology Internet | Diao S.-M.,China Life E commerce Company Ltd | And 3 more authors.
Physica A: Statistical Mechanics and its Applications | Year: 2016

In online social media, opinion divergences and differentiations generally exist as a result of individuals’ extensive participation and personalization. In this paper, a Susceptible–Hesitated–Infected–Removed (SHIR) model is proposed to study the dynamics of competitive dual information diffusion. The proposed model extends the classical SIR model by adding hesitators as a neutralized state of dual information competition. It is both hesitators and stable spreaders that facilitate information dissemination. Researching on the impacts of diffusion parameters, it is found that the final density of stiflers increases monotonically as infection rate increases and removal rate decreases. And the advantage information with larger stable transition rate takes control of whole influence of dual information. The density of disadvantage information spreaders slightly grows with the increase of its stable transition rate, while whole spreaders of dual information and the relaxation time remain almost unchanged. Moreover, simulations imply that the final result of competition is closely related to the ratio of stable transition rates of dual information. If the stable transition rates of dual information are nearly the same, a slightly reduction of the smaller one brings out a significant disadvantage in its propagation coverage. Additionally, the relationship of the ratio of final stiflers versus the ratio of stable transition rates presents power characteristic. © 2016 Elsevier B.V.

Wang A.-M.,North China University of Water Conservancy and Electric Power | Wang A.-M.,CAS Wuhan Institute of Rock and Soil Mechanics | Li X.-G.,North China University of Water Conservancy and Electric Power | Huang Z.-Q.,North China University of Water Conservancy and Electric Power | And 5 more authors.
Environmental Earth Sciences | Year: 2015

Concentrations of biotite flakes were distributed at multiple locations during the site investigation for the Tianchi Pumped Storage Power Station project in Henan Province, China. Rock mass was highly weathered on both sides of a prominent fault, and a large number of white and gray, locally yellow–brown, argillaceous agglomerations were observed. The local core at the end of the ZK44 hole presented a gray and white sandstone structure. Petrochemical tests, which included sheet identification, scanning electron microscopy, electron probe analysis, and X-ray diffraction, showed that the main alteration types were mica-rich-type altered rocks and clay-type altered rocks, which were accompanied by chlorite, epidote, actinolite, and other alteration minerals. According to the mechanical test results, the smallest antidisintegration index was 84 %, disintegration was easily accomplished, the maximum axial free expansion rate was 0.00204 %, the maximum free expansion rate in the radial direction was 0.0178 %, and maximum lateral constrained expansion rate was 0.0194 %. The swelling pressure of all the specimens did not exceed 10 kPa, and the clay-type altered rocks exhibited three large expansion parameters. Uniaxial and triaxial compression tests showed that the strength of granite, as reflected by its deformation and elastic moduli, decreased to values even lower than those of highly weathered rocks because of alteration. The poor characteristics of the altered rock presented great challenges for support or lining during the construction and operation stages. After excavation, the expanded altered rocks should be cleaned up immediately, the support or lining should be in place immediately, and water should be drained in time. © 2015, Springer-Verlag Berlin Heidelberg.

Xu D.,Hohai University | Lu B.,Hohai University | Cheng X.,Zhejiang University | Gu H.,Hohai University | And 4 more authors.
Journal of Hohai University | Year: 2013

Based on the layered vertical distribution of water temperature in reservoirs, a new method, which is called the logistic curve method, is proposed to estimate the water temperature. In this study, an S-type logistic curve equation was used to fit one year of observed data from the Xin'anjiang Reservoir. The results show a high accuracy of fitting by determining the parameters in the empirical equation(s) using the nonlinear regression method in the SPSS software. Meanwhile, the applicability of the empirical equation(s) was analyzed using observed data from other reservoirs. The results show that the empirical equation(s) can well fit the vertical distribution of water temperature in the reservoir for different types (the mixed type and stable layered type) in different periods (the temperature raising period and stable layered period). In addition, several approaches to obtaining the parameters are proposed for water temperature forecasting with the empirical equation(s).

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