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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

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 {4., 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

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 4..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

Soil erosion and sediment transport in the gullied Loess Plateau:Scale effects and their mechanisms

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Science china(Technological Sciences) 2009年第5期52卷 1283-1292页

作者： LI TieJian1,WANG GuangQian1,XUE Hai2,3 & WANG Kai4.1 State Key Laboratory of Hydroscience and Engineering,Tsinghua University,beijing 100084.china 2 Yellow River Engineering Consulting Co.,Ltd.,Zhengzhou 4.0003,china 3 North china Institute of {4. Conservancy and hydropower,Zhengzhou 4.0008,china 4.china Institute of {4. resources and hydropower research,beijing 100038,china State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing China Yellow River Engineering Consulting Co. Ltd. Zhengzhou China North china Institute of water Conservancy and hydropower Zhengzhou China china Institute of water resources and hydropower {4. Beijing China

Scale effects exist in the whole process of rainfall-3-runoff-3-soil erosion-3-sediment transport in river basins. The differences of hydrographs and sediment graphs in different positions in a river basin are treated as basic scale effects, which are more complex in the gullied Loess Plateau, a region notorious for high intensity soil erosion and hyper-concentrated sediment-laden flow. The up-scaling method of direct extrapolation that maintains dynamical mechanism effective in large scale application was chosen as the methodology of this paper. Firstly, scale effects of hydrographs and sediment graphs were analyzed by using field data, and key sub-processes and their mechanisms contributing to scale effects were clearly defined. Then, the Digital Yellow River Model that integrates sub-models for the subprocesses was used with high resolution to simulate rainfall-3-runoff-3-soil erosion-3-sediment transport response in Chabagou watershed, and the distributed results representing scale effects were obtained. Finally, analysis on the simulation results was carried out. It was shown that gravitational erosion and hyper-concentrated flow contribute most to the spatial variation of hydrographs and sediment graphs in the spatial scale. Different spatial scale distributions and superposition of different sub-processes are the mechanisms of scale effects.

关键词： scale effect soil erosion hyper-concentrated sediment-laden flow the Loess Plateau

Characteristics of the Lower Yellow River channel shrinkage and its discriminant parameters

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Science china(Technological Sciences) 2010年第5期53卷 1374-1386页

作者： HU ChunHong1 & ZHANG GuoGang2 1 china Institute of water resources and hydropower {4.,beijing 100038,china 2 Guangdong Electric Power Design Institute,Guangzhou 510663,china china Institute of water resources and hydropower {4. Beijing China Guangdong Electric Power Design Institute Guangzhou China

This paper analyzes the changing trends of the Lower Yellow River(LYR) transverse profile parameters and their aberrance points by the time series analysis *** results show that there has been a trend of changes in the LYR channel transverse profile parameters since the *** main river channel has a tendency of shrinkage year by year and the trend will be continued in the *** main features of the LYR channel shrinkage are remarkable reductions of bankfull dis-charges and bankfull areas,corresponding decreases of bankfull widths,average bankfull water depths and maximal bankfull water depths,as well as increases of bankfull water levels and width-depth ratios *** discriminant parameters for threshold of the LYR main channel shrinkage were put *** indicates that the LYR main channel began to shrink in the 1970s and has entered into a serious phase of channel shrinkage since the *** incompatible index of discharged water-sediment processes of the Sanmenxia Reservoir was introduced,which revealed that there was a trend of increasing in the incompatibility between water flow and sediment *** relations between the LYR main channel shrinkage parameters and discharged water-sediment processes of the Sanmenxia Reservoir were founded,which indicate that the LYR main channel shrinkage can be mitigated and improved through the regulation of discharged water-sediment processes of the reservoir,especially through the regulation of water-sediment incompatible *** LYR channel for water and sediment transportation can be restored and maintained.

关键词： Lower Yellow River time series analysis main river channel shrinkage discriminant parameters of channel shrinkage water-sediment incompatible index

Hydraulic characteristics of converse curvature section and aerator in high-head and large discharge spillway tunnel

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Science china(Technological Sciences) 2011年第S1期54卷 33-39页

作者： LIU ZhiPing 1,2,ZHANG Dong 2,ZHANG HongWei 2 &WU YiHong 1,2 1 State Key Laboratory of Simulation and Regulation of water Cycle in River Basin,beijing 100038,china 2 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 china Institute of water resources and hydropower {4. Beijing China

The hydraulic characteristics and cavitation erosion near the converse curvature section in the high-head and large discharge spillway tunnel have been important issues of concern to the hydropower *** this paper,the evolutions of hydraulic elements such as pressure,flow velocity,wall shear stress,*** the converse curvature section are analyzed and the impacts of bottom aerator on hydraulic characteristics are discussed,with the commercial software FLUENT6.3 as a platform and combining the k-model and VOF *** flow pattern in the converse curvature section of spillway tunnel is given by the three-dimensional numerical *** indicates that the pressure changes rapidly with great pressure gradient from the beginning to the end of the *** also shows that the shear stress on side wall just downstream the end of the converse curvature curve is still increasing;the aeration cavity formed downstream the bottom aerator may cause the side wall pressure decreased to worsen the cavitation characteristics near the side *** means of the physical model experiment,the three-dimensional aerator composed of side wall baffling aerator and bottom aerator is studied,the baffling aerator suitable for the water flow conditions with water depth of 6.0 to 8.0 m and flow velocity of 35 to 50 m/s is proposed.

关键词： spillway tunnel baffling aerator converse curvature section hydraulic characteristics

Temporal and spatial distribution of dam failure events in china

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International Journal of Sediment research 2008年第4期23卷 398-405页

作者： X.Y.HE 1,Z.Y.WANG 2,and J.C.HUANG 31 Senior Engineer,Department of water Hazard research,china Institute of water {4. and hydropower research,beijing 100038,china2 Prof.,State Key Laboratory of Hydroscience and Engineering,Tsinghua University,beijing 100084.china 3 Prof.,Department of water Hazard research,china Institute of water {4. and hydropower research,beijing 100038,china Senior Engineer Department of Water Hazard Research China Institute of Water Resources and Hydropower Research Beijing 100038 China Prof. State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Prof. Department of Water Hazard Research China Institute of Water Resources and Hydropower Research Beijing 100038 China

Reservoirs play a vital role in economic development and flood control. Nevertheless, both human and natural factors may lead to dam failures with catastrophic consequences. Analyzing the data of dam failure events from 1954.to 2003 and using the method of energy spectrum analysis, this paper studies the periodicity of dam failures. The rate of failure of different dam ages is analyzed. The climate is the main factor affecting the rate of dam failure. Climate diagrams are used to analyze the spatial distribution of dam failure events in china. High rate of dam failure occurs with 25-year and 12.5-year periods. The distribution of the percentage of dam failure shows an L-shape as a function of service age. The first 5 years of operation is known as the "infant period", during which, the probability of dam failure is much higher than during any other periods. The failure rate in areas near or north to the 4.0 mm annual isopluvial line is notably higher than other areas. In areas with high temperature difference among seasons have a high annual average dam failure rate.

关键词： Dam failure Temporal and spatial distribution Service age Climate diagram

Modified vegetation-erosion dynamics model and its application in typical watersheds in the Loess Plateau

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International Journal of Sediment research 2011年第1期26卷 78-86页

作者： CHEN Yuehong~1,WANG Feixin~2,LIU Guangquan~3,YU Xinxiao~4. JIA Guodong~5,and GAN Ping~6 china Institute of water resources and hydropower {4.,beijing 10004. International {4. and Training Center on Erosion and Sediment {4.,beijing 10004.,china beijing Forestry University,beijing 100083,china. Key Lab of Dredging Technology of CCGRP,Shanghai waterway Engineering Design and Consulting Co., Ltd,Shanghai 200120,china. International {4. and Training Center on Erosion and Sedimentation china Institute of water resources and hydropower {4.,beijing 10004. Northwest A&F University,Yangling 712100,china, beijing Forestry University,beijing 100083,china, beijing Forestry University,beijing 100083,china. china Institute of water resources and hydropower {4.,beijing 10004.,and International {4. and Training Center on Erosion and Sediment {4.,beijing 10004.,china Assoc. Prof. Dr. China Institute of Water Resources and Hydropower Research Beijing 100048 International research and Training Center on Erosion and Sediment research Beijing 100048 China beijing Forestry University Beijing 100083 China Dr. Key Lab of Dredging Technology of CCGRP Shanghai Waterway Engineering Design and Consulting Co. Ltd Shanghai 200120 China Prof. Dr. International Research and Training Center on Erosion and Sedimentation china Institute of water resources and hydropower {4. Beijing 100048 Northwest A&F University Yangling 712100 China Prof. Dr. Beijing Forestry University Beijing 100083 China Dr. Beijing Forestry University Beijing 100083 China Engineer China Institute of Water Resources and Hydropower Research Beijing 100048 and International Research and Training Center on Erosion and Sediment Research Beijing 100048 China

The vegetation-erosion model was applied in three typical watersheds of hilly and gully area in the Loess Plateau in northwestern china to study the dynamic relations between vegetation coverage and soil erosion rate and various *** model was improved by introducing rainfall and runoff *** the modified model was applied in the Luergou and Luoyugou *** calculation results with the modified model were compared with the results of the original *** precisions of simulated vegetation coverage and soil erosion rate with the modified model were greatly improved compared with the original *** erosion rate reduced with increasing vegetation coverage and the human disturbance caused high soil erosion.

关键词： Soil erosion Vegetation coverage Vegetation-erosion dynamics model Loess Plateau Modified model

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 10004.2}) (2State Key Laboratory of Simulation and Regulation of water Cycle in River Basin,{4. Institute of water resources and hydropower research,beijing 100038,{4.) 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