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Study on real working performance and overload safety factor of high arch dam

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Science china(Technological Sciences) 2008年第S2期51卷 48-59页

作者： ZHANG GuoXin,LIU Yi & ZHOU QiuJing Department of Structures and Materials,china institute of water resources and hydropower research,beijing 100038,china Department of Structures and Materials China Institute of Water Resources and Hydropower Research Beijing China

Considering the fact that high arch dams have problems such as complicated stress,high cost,and hazards after being damaged,this paper intends to study the effects of load,material strength,and safety analysis method on dam safety and working performance of arch *** this article,the effects of temperature,self weight exaction way and water loading on structure response are first discussed,and a more reasonable way of considering is then put *** taking into consideration the mechanical property of materials and comparing the effects of different yield criteria on overloading safety of high arch dams,this paper concludes that brittle characteristics of concrete should be fully considered when conducting safety assessment for high arch dams to avoid overestimating the bearing capacity of the *** comparing several typical projects,this paper works out a safety assessment system of multiple safety and relevant engineering analogical analysis methods,which is closer to the actual situation,and thus is able to assess the response of high arch dam structure in a more comprehensive way,elicit the safety coefficients in different situations,and provide a new way of considering the safety assessment of high arch dams.

关键词： high arch dam real working performance safety load strength safety assessment method

Investigation of the 5.12 Wenchuan Earthquake damages to the Zipingpu water Control Project and an assessment of its safety state

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Science china(Technological Sciences) 2009年第4期52卷 820-834页

作者： GUAN ZhiCheng water resources and hydropower Planning & Design General institute, beijing100120, china water resources and hydropower Planning & Design General institute Beijing China

On May 12, 2008, a major earthquake measured 8 on the Richter scale jolted Wenchuan County in Si- chuan Province, china with the epicentral intensity of XI degrees. Zipingpu Dam is located 17.17 km from the epicenter and the influence intensity at the damsite reached IX―X degrees. It is the first time in the world for such a high concrete-faced rockfill dam (CFRD) in china to experience such a strong earthquake occurring in such a short distance. Due to its location of special importance to the down- stream areas, the safety state and damaging condition of the Zipingpu Dam has attracted great atten- tions from various circles. Based on site investigation of the damages to the Zipingpu Dam and com- parison analysis of the observation data obtained before and after the earthquake, the paper makes a comprehensive assessment of the key technical issues relevant to this high CFRD, including its safety state and the high slope stability after the earthquake.

关键词： earthquake earthquake damage investigation concrete-faced rockfill dam dam project safety state Zipingpu Dam

NUMERICAL COMPUTATION OF VERTICAL TWO-DIMENSIONALNON-EQUILIBRIUM SEDIMENT MOVEMENT

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International Journal of Sediment research 1999年第2期14卷 251-257页

作者： HUANG Yongiian (1 china institute of water resources and hydropower research, P.O.Box 366,beijing 100044.)

Non-equilibrium sediment transport is studied by using a numerical solution of vertical two dimensional diffusion equations. Sediment concentration on the bed is determined as the boundary condition of diffusion equation based the sediment carrying capacity of local flow. The velocity field is solved and then the two dimensional diffusion equations in each section along the flow direction are solved. The vertical distribution of sediment concentration is determined and then the quantities of erosion or siltation are obtained along the cross sections. The usage of this numerical computation method is further explained in unsteady flow examples.

关键词： Non-equilibrium sediment transport Sediment concentration Numerical model Velocity field

A STUDY ON THE WARPING NEAR IRRIGATION HEADWORKOF THE LOWER REACH OF YELLOW RIVER

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International Journal of Sediment research 1999年第2期14卷 399-404页

作者： HUANG Jinchi WANG Yangui (china institute of water resources and hydropower research, Fuxinglu, A-l, beijing,100038, china)

The Yellow River is famous for its tremendous amount of sediment transport. Through a careful settlement, large amount of sediment laden flow can be diverted out for warping. however. for successfully completing a warping process, a series of technical measures must be taken and a precisely pre-planning is necessary. In this paper, a general description on the warping for soil improvement has been provided; some technical problems for a successful warping process were put forward and finally. a practical designing example on silt filling at headwork of an irrigation project is examined. The case study shows that drawing of flood water at hyper-concentration of sediment for warping is an effective measure to fully utilize water and sediment resources in the Lower Yellow River.

关键词： Warping Sediment transport Lower Yellow River

Simulation of influence of multi-defects on long-term working performance of high arch dam

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Science china(Technological Sciences) 2011年第S1期54卷 1-8页

作者： ZHANG GuoXin ,LIU Yi,ZHENG CuiYing & FENG Fan State Key Laboratory of Simulation and Regulation of water Cycle in River Basin,beijing 100038,china china institute of water resources and hydropower research,beijing 100038,china State Key Laboratory of Simulation and Regulation of water Cycle in River Basin Beijing China

As an integrated structure,an arch dam is assumed to bear loads in its design ***,multi-defects,such as cracks and the opening of transverse joints,are unavoidable during construction and ***-defects will reduce the structural integrity and stiffness of the dam and affect its working performance and degree of *** the current paper,a numerical model of defects and a simulation method of a high arch dam are *** Chencun arch dam is analyzed as a case *** entire course simulation analysis of the Chencun arch dam from construction to operation is carried out,through which the opening of the transverse and longitudinal joints,formation of cracks,and their influence on deformation and stress of the dam are *** to the results of the analysis,appropriate measures should be adopted to prevent the development of cracks,and observation should be strengthened for a more timely discovery of risks.

关键词： high arch dam crack multi-defects working performance

Numerical simulation of two-phase turbulent flow in hydraulic and hydropower engineering

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Science china(Technological Sciences) 2007年第Z1期50卷 79-89页

作者： DAI HuiChao1,2?, WANG LingLing1, GAO JiZhang3, ZHANG XiaoDong3 & YANG ZhongHua2 1 College of water Conservancy and hydropower Engineering, Hohai University, Nanjing 210098, china 2 china Yangtze River Three Gorges Project Development Corporation, Yichang 443002, china 3.china institute of water resources and hydropower research, beijing 100044, china College of water Conservancy and hydropower Engineering Hohai University Nanjing China china Yangtze River Three Gorges Project Development Corporation Yichang China china institute of water resources and hydropower research Beijing China

In connection with the specific features of high velocity aerated flow generated by hydraulic engineering structures, the mathematical model is developed for high turbulence air-water two-phase flow with the use of twin flow theoretical model in this paper. Furthermore the numerical method is proposed to treat bubbled flows. In addition, on the basis of air-water stratified twin flow model, the new calculation methods and free surface tracking technique are proposed to describe complicated movements of the free surface. Finally, the proposed model is used to calculate artificial aerated flows. The computed results coincide quite well with experimental results. This means that the proposed method can provide solid basis for practical engineering design.

关键词： high turbulence two-phase flow twin flow model aerated flow free surface

A COUPLED MODEL OF HYDRODYNAMICS AND water QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of Environment Beijing Normal University Beijing 100875 China Department of water Environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

On the formation of couplet-style stratifications

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International Journal of Sediment research 2008年第1期23卷 85-91页

作者： Yu-Hai WANG1, Yan-Hong WANG2, and Li-Qun TANG31 Ph.D., Engineer, Department of Sediment research, china institute of water resources and hydropower research, Chegongzhuangxilu 20, beijing 100044, china, 2 Ph.D., Engineer, Nanjing Hydraulic research institute, Hujuguanlu 34, Nanjing 210024, china 3 Ph.D., Prof., Department of Sediment research, china institute of water resources and hydropower research, Chegongzhuangxilu 20, beijing 100044, china Ph.D. Engineer Department of Sediment Research China Institute of Water Resources and Hydropower Research Chegongzhuangxilu 20 Beijing 100044 China Ph.D. Engineer Nanjing Hydraulic Research Institute Hujuguanlu 34 Nanjing 210024 China Ph.D. Prof. Department of Sediment Research China Institute of Water Resources and Hydropower Research Chegongzhuangxilu 20 Beijing 100044 China

Couplet-style stratifications refer to the sedimentary sequences that consist of alternating coarse-grain-dominated bed and fine-grain-dominated bed, with or without a sandwiched middle-sized bed. The formation mechanism is complicated due to the interplays of varying driving force (s), sediment supply & transport and topographic configurations. This paper presents a comprehensive overview of such characteristic bedforms, which emerge during the transport and deposition of non-uniform sediments. The leading formative models include water-stage variation, gravel-overpassing process, superimposition of bedload sheets and avalanching process (inverse grading). Each process might produce similar or distinct sedimentological features with respect to grading, matrix content, grain attitude, bounding faces between beds and internal longitudinal/transverse geometry. The couplet-style stratified strata might play an active role in landscape evolution.

关键词： Couplet-style stratification Formative model Sedimentological features Landform

Experiments and sensitivity analyses for heat transfer in a meter-scale regularly fractured granite model with water flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第12期13卷 958-968页

作者： Wei LU1,2,Yan-yong XIANG1 (1School of Civil Engineering,beijing Jiaotong University,beijing 100044,china) (2State Key Laboratory of Simulation and Regulation of water Cycle in River Basin,china institute of water resources and hydropower research,beijing 100038,china) School of Civil Engineering Beijing Jiaotong University Beijing China State Key Laboratory of Simulation and Regulation of water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing China

Experiments of saturated water flow and heat transfer were conducted for a meter-scale model of regularly fractured granite. The fractured rock model （height 1502.5 ram, width 904 mm, and thickness 300 mm）, embedded with two vertical and two horizontal fractures of pre-set apertures, was constructed using 18 pieces of intact granite. The granite was taken from a site currently being investigated for a high-level nuclear waste repository in china. The experiments involved different heat source temperatures and vertical water fluxes in the embedded fractures either open or filled with sand. A finite difference scheme and computer code for calculation of water flow and heat transfer in regularly fractured rocks was developed, verified against both the experimental data and calculations from the TOUGH2 code, and employed for parametric sensitivity analyses. The experiments revealed that, among other things, the temperature distribution was influenced by water flow in the fractures, especially the water flow in the vertical fracture adjacent to the heat source, and that the heat conduction between the neighboring rock blocks in the model with sand-filled fractures was enhanced by the sand, with larger range of influence of the heat source and longer time for approaching asymptotic steady-state than those of the model with open fractures. The temperatures from the experiments were in general slightly smaller than those from the numerical calculations, probably due to the fact that a certain amount of outward heat transfer at the model perimeter was unavoidable in the experiments. The parametric sensitivity analyses indicated that the tem- perature distribution was highly sensitive to water flow in the fractures, and the water temperature in the vertical fracture adjacent to the heat source was rather insensitive to water flow in other fractures.

关键词： Fractured granite water flow Heat transfer Physical modeling Numerical calculation Sensitivity analysis