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Damming effects on dissolved inorganic carbon in different kinds of reservoirs in Jialing River,Southwest China 被引量:4
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作者 Gaoyang Cui Xiaodong Li +4 位作者 Qinkai Li Jun Huang Yuele Tao Siqi Li Jun Zhang 《Acta Geochimica》 EI CAS CSCD 2017年第4期581-597,共17页
To assess the effects of river damming on dissolved inorganic carbon in the Jialing River, a total of 40 water samples, including inflow, outflow, and stratified water in four cascade reservoirs(Tingzikou, Xinzheng,Do... To assess the effects of river damming on dissolved inorganic carbon in the Jialing River, a total of 40 water samples, including inflow, outflow, and stratified water in four cascade reservoirs(Tingzikou, Xinzheng,Dongxiguan, Caojie) were collected in January and July,2016. The major cations, anions, and δ^(13)C_(DIC) values were analyzed. It was found that the dissolved compositions are dominated by carbonate weathering, while sulfuric acids may play a relatively important role during carbonate weathering and increasing DIC concentration. Different reservoirs had variable characteristics of water physiochemical stratification. The DIC concentrations of reservoir water were lower in summer than those in winter due to the dilute effects and intensive aquatic photosynthesis, as well as imported tributaries. The δ^(13)C_(DIC) values in Tingzikou Reservoir were higher during summer than those in winter,which indicated that intensive photosynthesis increased the δ^(13)C_(DIC) values in residual water, but a similar trend was not obvious in other reservoirs. Except for in Xinzheng Reservoir, the δ^(13)C_(DIC) values in inflow and outflow reservoir water were lower than those in the surface water of stratified sampling in summer. For stratified sampling, it could be found that, in summer, the Tingzikou Reservoir δ^(13)C_(DIC) values significantly decreased with water depthdue to the anaerobic breakdown of organic matter. The significant correlation(p<0.01 or 0.05) between the DIC concentrations, the δ^(13)C_(DIC) values and anthropogenic species(Na^++K^+, Cl~–, SO_4^(2-) and NO_3^-) showed that the isotope composition of DIC can be a useful tracer of contaminants. In total, Tingzikou Reservoir showed lacustrine features, Xinzheng Reservoir and Dongxiguan Reservoir had "transitional'' features, and Caojie Reservoir had a total of "fluvial'' features. Generally, cascade reservoirs in the Jialing River exhibited natural river features rather than typical lake features due to characteristics of reservoir water in physiochemical stratification, spatiotemporal variations of DIC concentrations and isotopic compositions. It is evident that the dissolved inorganic carbon dynamics of natural rivers had been partly remolded by dam building. 展开更多
关键词 River damming Water chemistry reservoir types Dissolved inorganic carbon isotope composition DIC concentration
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Numerical Simulation of Dam-Break Flooding of Cascade Reservoirs 被引量:3
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作者 Zhengyin Zhou Xiaoling Wang +2 位作者 Wenlong Chen Shaohui Deng Minghui Liu 《Transactions of Tianjin University》 EI CAS 2017年第6期570-581,共12页
Previous studies at home and abroad have mainly focused on single dam-break, and little attention has been paid so far to the dam-break of cascade reservoirs. Multi-source flooding, which can lead to three-dimensional... Previous studies at home and abroad have mainly focused on single dam-break, and little attention has been paid so far to the dam-break of cascade reservoirs. Multi-source flooding, which can lead to three-dimensional turbulent phenomena and superposition effects, is the main difference between the dam-break of cascade and single reservoirs. Detailed descriptions of the coupled numerical simulation of multi-source flooding have little been reported, and the initial wet riverbed is rarely considered in current models. Therefore, in this paper, a method based on the three-dimensional (Formula presented.) turbulence model coupled with the volume-of-fluid method is proposed to simulate the dam-break flooding of cascade reservoirs. The upstream river, reservoir, and downstream river are connected by the internal boundary method, and the initial conditions, including river flow and reservoir water, are determined according to the results of the numerical simulation. Coupled numerical simulation of different dam-break flooding is then achieved. The present work solves the challenges presented by the enhancement and superposition of natural river flow, upstream flooding, and downstream flooding. This paper provides a theoretical basis for future studies on the dam-break flood routing of cascade reservoirs. © 2017 Tianjin University and Springer-Verlag GmbH Germany 展开更多
关键词 dams Floods Flow of water Numerical methods Numerical models RIVERS Stream flow Turbulence models
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Lessons learned from Wenchuan earthquake for seismic safety of large dams 被引量:2
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作者 Chen Houqun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第2期241-249,共9页
This paper describes some special features of the Wenchuan earthquake that affected dam safety. Damage and performance of dams, primarily for four dams over 100 m high located in the affected earthquake area, are brie... This paper describes some special features of the Wenchuan earthquake that affected dam safety. Damage and performance of dams, primarily for four dams over 100 m high located in the affected earthquake area, are briefly described. Lessons learned related to dam safety from this devastating earthquake are preliminarily drawn. As the seismic safety of high dams during strong earthquakes has gained more attention around the world, some critical issues related to dam construction in China are considered and extensively discussed. Questions such as "Why is dam construction necessary in earthquake prone countries such as China?", "Can we accurately evaluate the seismic safety of high dams in China?", "Did reservoir impounding of the Zipingpu and Three Gorges Projects trigger the Wenchuan Earthquake in some way?" and "What is the strategic priority of dam safety for large dams in China?" are discussed. Finally, the corresponding tactics with response to the challenge are suggested and recent preliminary progress mainly achieved in IWHR is briefly introduced. 展开更多
关键词 Wenchuan earthquake dam safety LESSON reservoir earthquake strategic priority
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A quantitative model for danger degree evaluation of staged operation of earth dam reservoir in flood season and its application 被引量:3
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作者 Chong-xun Mo Gui-yan Mo +3 位作者 Qing Yang Yu-li Ruan Qing-ling Jiang Ju-liang Jin 《Water Science and Engineering》 EI CAS CSCD 2018年第1期81-87,共7页
Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for ... Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for the overtopping risk rate of the earth dam reservoir staged operation was established, with consideration of the joint effect of flood and wind waves in the flood sub-seasons with the Monte Carlo method, and the integrated overtopping risk rate for the whole flood season was obtained via the total probability approach. A composite normalized function was used to transform the dam overtopping risk rate into the danger degree, on a scale of 0-1. Danger degree gradating criteria were divided by four significant characteristic values of the dam overtopping rate, and corresponding guidelines for danger evaluation are explained in detail in this paper. Examples indicated that the dam overtopping danger degree of the Chengbihe Reservoir in China was 0.33-0.57, within the range of moderate danger level, and the flood-limiting water level (FLWL) can be adjusted to 185.00 m for the early and main flood seasons, and 185.00-187.50 m for the late flood season. The proposed quantitative model offers a theoretical basis for determination of the value of the danger degree of an earth dam reservoir under normal operation as well as the optimal scheduling scheme for the reservoir in each stage of the flood season. 展开更多
关键词 reservoir staged operation in flood season Earth dam Danger degree Quantitative evaluation Overtopping risk rate
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Dynamic analysis of dam-reservoir-foundation interaction using finite difference technique 被引量:2
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作者 M.Abdollahi R.Attarnejad 《Journal of Central South University》 SCIE EI CAS 2012年第5期1399-1410,共12页
Time domain dynamic analysis of inclined dam-reservoir-foundation interaction was conducted using finite difference method (FDM). The Timoshenko beam theory and the Euler-Bemoulli beam theory were implemented to dra... Time domain dynamic analysis of inclined dam-reservoir-foundation interaction was conducted using finite difference method (FDM). The Timoshenko beam theory and the Euler-Bemoulli beam theory were implemented to draw out governing equation of beam. The interactions between the dam and the soil were modeled by using a translational spring and a rotational spring. A Sommerfeld's radiation condition at the infinity boundary of the fluid domain was adopted. The effects of the reservoir bottom absorption and surface waves on the dam-reservoir-foundation interaction due to the earthquake were studied. To avoid the instability of solution, a semi-implicit scheme was used for the discretization of the governing equation of dam and an explicit scheme was used for the discretization of the governing equation of fluid. The results show that as the slope of upstream dam increases, the hydrodynamic pressure on the dam is reduced. Moreover, when the Timoshenko beam theory is used, the system response increases. 展开更多
关键词 dam-reservoir-foundation interaction inclined dam explicit method semi-implicit method reservoir bottomabsorption free surface waves
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Channel Evolution of Sandy Reservoir Sediments Following Low-Head Dam Removal, Ottawa River, Northwestern Ohio, U.S.A. 被引量:1
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作者 Nathan Harris James E. Evans 《Open Journal of Modern Hydrology》 2014年第2期44-56,共13页
Dozens of low-head dams are removed annually for reasons of obsolescence, financial liability, public safety, or as part of aquatic ecosystem restoration. Prior to removing a dam, hydrologic and sedimentologic studies... Dozens of low-head dams are removed annually for reasons of obsolescence, financial liability, public safety, or as part of aquatic ecosystem restoration. Prior to removing a dam, hydrologic and sedimentologic studies are used to predict channel changes that would occur after the proposed dam removal. One commonly used predictive approach is a channel evolution model (CEM). However, most CEMs assume that the reservoir has trapped cohesive silts and muds. This study looks at the effects of low-head dam removal on a reservoir in filled with sand-rich sediment. The Secor Dam (2.5 m tall, 17 m wide) was constructed on the Ottawa River in northwestern Ohio (USA) during 1928 and was removed in 2007. High resolution channel cross-sections were measured at 17 locations prior to dam removal and re-measured every approximately 30 days for 6 months following the removal. Sediment sampling, sediment traps, substrate sampling, differential GPS tracking of channel bed forms and sediment coring were also used to characterize the channel sediment response to dam removal. Breaching of the dam produced a diffuse nickzone which was the width of the channel and about 10 m in length. One initial response was downstream migration of a sediment wave at rates up to 0.5 m/hr. The overall effect was erosion of the former reservoir to a distance of 150 m upstream of the former dam. Portions of the former reservoir were incised >1 m. Within the first 6 months after removal, approximately 800 m3 of sand had been mobilized from the former reservoir, transported downstream past the former dam, and had primarily in-filled pre-existing pools within a reach approximately 150 m downstream of the former dam. This behavior significantly differs from the predicted results of current CEMs which anticipate a first flush of suspended sediment and minor deposition of bed load materials in the channel downstream of the former dam. 展开更多
关键词 dams reservoir Sediment dam Removals Channel Evolution Model (CEM)
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Monitoring and Evaluating the Sedimentation Process in Mosul Dam Reservoir Using Trap Efficiency Approaches 被引量:1
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作者 Issa E. Issa Nadhir Al-Ansari +1 位作者 Sven Knutsson Govand Sherwany 《Engineering(科研)》 2015年第4期190-202,共13页
Reservoirs are usually exposed to sediment accumulation problems that will lead to reduction in their storage capacity. This problem directly affects the performance of the dams and causes shortage of their useful lif... Reservoirs are usually exposed to sediment accumulation problems that will lead to reduction in their storage capacity. This problem directly affects the performance of the dams and causes shortage of their useful life. The simplest technique to estimate sediment deposition rate is using sediment rating curve with sediment trapping efficiency (TE) of the reservoir. Many empirical and semi-empirical approaches have been suggested for to determine this term depending on the annual inflow rate, reservoir characteristics and features of the catchments area. In this study six different empirical methods depending on the residence time principle (water retention time) were used. These approaches were reviewed and applied to determine TE of Mosul dam reservoir (MDR) for period 1986 to 2011. The monthly operating data for inflow, outflow and water elevations for MDR were used to determine monthly TE and long-term TE for whole period of MDR using the mentioned methods. Furthermore, the monthly inflow rate for River Tigris upstream MDR, its sediment rating curve and sediment feeding from valleys around MDR were used to estimate the amount sediment coming to the reservoir. The results provided by these methods for TE with sediment coming to MDR were used to compute the amount of sediment deposited in MDR on monthly bases during this period. The results obtained were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the dam. The results showed all the mentioned methods gave convergent results and they were very close to bathymetric survey results for estimating the volume of sediment deposited especially that proposed by Ward which gave 0.368% percentage error. Furthermore, the result computed using monthly TE gave good agreement if compared with that long-term TE where the percentage error was ranging between –3.229% to 1.674% for monthly adopted data and –4.862% to?–2.477% for whole period data. It is believed that this work will help others to use this procedure on other reservoirs. 展开更多
关键词 Losing Storage Capacity Mosul dam reservoir SEDIMENTATION SEDIMENT TRAP Efficiency
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Seismic safety of high concrete dams 被引量:3
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作者 Chen Houqun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第S1期1-16,共16页
China is a country of high seismicity with many hydropower resources. Recently,a series of high arch dams have either been completed or are being constructed in seismic regions,of which most are concrete dams. The eva... China is a country of high seismicity with many hydropower resources. Recently,a series of high arch dams have either been completed or are being constructed in seismic regions,of which most are concrete dams. The evaluation of seismic safety often becomes a critical problem in dam design. In this paper,a brief introduction to major progress in the research on seismic aspects of large concrete dams,conducted mainly at the Institute of Water Resources and Hydropower Research(IWHR) during the past 60 years,is presented. The dam site-specific ground motion input,improved response analysis,dynamic model test verification,field experiment investigations,dynamic behavior of dam concrete,and seismic monitoring and observation are described. Methods to prevent collapse of high concrete dams under maximum credible earthquakes are discussed. 展开更多
关键词 review and prospect seismic safety high concrete dam dam-foundation-reservoir interaction damage-rupture process
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Sedimentation Processes and Useful Life of Mosul Dam Reservoir, Iraq 被引量:1
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作者 Issa EIssa Nadhir Al-Ansari +1 位作者 Govand Sherwany Sven Knutsson 《Engineering(科研)》 2013年第10期779-784,共6页
The sedimentation process is the most important problems that affects directly the performance of reservoirs due to the reduction of the storage capacity and possible problems effecting the operation. Thus periodic as... The sedimentation process is the most important problems that affects directly the performance of reservoirs due to the reduction of the storage capacity and possible problems effecting the operation. Thus periodic assessment of the storage capacity and determining sediment deposition patterns is an important issue for operation and management of the reservoirs. In this study, bathymetric survey results and an analytical approach had been used to assess the characteristics of sedimentation and estimate the useful life of Mosul Reservoir. It is located on the Tigris River in the north of Iraq. The water surface area of its reservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330 m a.s.l). The dam started operating in 1986. No detailed study was yet carried out to assess its reservoir. The present study indicated that the annual reduction rate in the dead and live storage capacities of the reservoir is 0.786% and 0.276% respectively. The observed results (bathymetric survey) and algebraic formula show approximately that the useful life of Mosul dam reservoir is about 125 years. Furthermore, the stage-storage capacity curves for the future periods (prediction curves) were established using bathymetric survey data. 展开更多
关键词 Bathymetric Survey Mosul dam reservoir Sedimentation Rate Useful Life of reservoir
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Using of GIS Spatial Analyses to Study the Selected Location for Dam Reservoir on Wadi Al-Jirnaf, West of Shirqat Area, Iraq
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作者 Sabbar Abdulla Salih Abdul Salam Mehdi Al-Tarif 《Journal of Geographic Information System》 2012年第2期117-127,共11页
The GIS data of digital elevation model, topographic maps of different scales, satellite images and GPS were used to analyze the geometrical relations, bathometric properties and shape form of selected depressions on ... The GIS data of digital elevation model, topographic maps of different scales, satellite images and GPS were used to analyze the geometrical relations, bathometric properties and shape form of selected depressions on Al-Jirnaf valley. GIS was used to analyze the hydromorphometry and geometry of the depressions, these analyses explain the role of main valley’s contribution to the hydrology of the valley, then, three locations for water storage were suggested. 2D and 3D models of the sites were given, the maximum level, volume, surface area, circumference, shape factor of three supposed reservoirs calculated for different hypothetical levels of water in the reservoir, and the optimal level were determined, the maximum suggested levels are 190, 185 and 180 m, the areas are 3.25, 7.97 and 20.47 km2, the volumes are 0.0096, 0.0334 and 0.1118 km3 for the three locations respectively. This experimental procedure can be repeated in other depressions for the same purpose. 展开更多
关键词 GIS SPATIAL Analysis Geometry dam reservoir Iraq
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Possibilities of Using Dam Reservoir Sediments in Earthworks
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作者 Karolina Kos 《Journal of Environmental Science and Engineering(B)》 2015年第7期380-387,共8页
A possibility of using bottom sediments from dam reservoir as a material for earthen embankments was considered in the paper. It was stated that sediments cannot be used for road or hydrotechnical embankments without ... A possibility of using bottom sediments from dam reservoir as a material for earthen embankments was considered in the paper. It was stated that sediments cannot be used for road or hydrotechnical embankments without improving their geotechnical parameters. Thanks to low values of the permeability coefficient, they can be used for sealing elements in embankments or for low levees. In order to verify usability of this material for mentioned levees, stability and filtration calculations were carried out using Finite Element Method (FEM) analysis. It was stated the levee built from bottom sediments is stable even at the height of 8.0 m, despite the boundary conditions on the upstream side. 展开更多
关键词 dam reservoirs DREDGING stability.
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Geomatics-Based Framework for Assessing Environmental Impacts of Grand Ethiopian Renaissance Dam (GERD) Reservoir
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作者 Mahmoud A. Hassaan 《Journal of Geoscience and Environment Protection》 2021年第12期72-83,共12页
Despite the benefits of big project dams, their reservoirs may have significant environmental impacts. The main objective of this paper is to develop an integrated analysis framework of remotely-sensed data ad GIS tec... Despite the benefits of big project dams, their reservoirs may have significant environmental impacts. The main objective of this paper is to develop an integrated analysis framework of remotely-sensed data ad GIS techniques for delineating surface area of </span><span><span style="font-family:"">the </span></span><span><span style="font-family:"">dam reservoir, simulating their capacities and assessing associated environmental impacts with application to Grand Ethiopian Renaissance Dam (GERD). For this purpose, a methodology of four main steps was applied. The methodology involved delineating </span></span><span><span style="font-family:"">the </span></span><span><span style="font-family:"">up-to-date reservoir using remotely sensed data, simulating reservoir at full capacity, estimating current and potential reservoir capacity and finally assessing environmental impacts of the reservoir. The results revealed that the up-to-date reservoir covers a total area of 330.3 km<sup>2</sup> with </span></span><span><span style="font-family:"">a </span></span><span><span style="font-family:"">gross storage capacity of 12 billion m<sup>3</sup>. Under full capacity scenario, the reservoir is estimated to cover a total area of 1650.9 km<sup>2</sup>, with </span></span><span><span style="font-family:"">a </span></span><span><span style="font-family:"">storage capacity of 63.4 billion m<sup>3</sup>. </span></span><span><span style="font-family:"">The </span></span><span><span style="font-family:"">GERD reservoir may lead to dramatic changes in the local environment with significant implications at both regional and global scales. In this respect, it was found that the reservoir will lead to destruction of ecosystems in a total area of 1300 km<sup>2</sup> covered by grasslands and Savannah. Also, </span></span><span><span style="font-family:"">the </span></span><span><span style="font-family:"">GERD reservoir is expected to have significant impacts on GHGs emissions and global warming. Moreover, </span></span><span><span style="font-family:"">a </span></span><span><span style="font-family:"">massive quantity of water is expected to be lost by surface evaporation. 展开更多
关键词 Remote Sensing GIS dams reservoirs GERD
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Simulation of Ground Motion at Guanting Reservoir Dam Based on the Scenario Earthquake in the Yanqing-Huailai Basin
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作者 Wen Yanjun 《Earthquake Research in China》 2009年第4期458-466,共9页
Research at home and abroad shows that the simulation of ground motion using the 3D finite-difference method might be accurate and feasible. Based on related theories and methods,and using the wave velocity and densit... Research at home and abroad shows that the simulation of ground motion using the 3D finite-difference method might be accurate and feasible. Based on related theories and methods,and using the wave velocity and density model of the crust in the Yanqing-Huailai Basin,this paper makes a simulation of ground motion at Guanting Reservoir Dam based on the scenario earthquake in the Yanqing-Huailai Basin. Comparative analysis shows that the results of 3D finite-difference simulation accord with those of the empirical formula. The parameters such as the velocity-time series of ground motion,PGV and frequency might be referred to for the analysis of seismic protection design of the dam's structure. 展开更多
关键词 Yanqing-Huailai Basin Guanting reservoir dam Scenario earthquake Simulation of ground motion
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Reservoir water effects on earthquake performance evaluation of Torul Concrete-Faced Rockfill Dam
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作者 Alemdar BAYRAKTAR Murat Emre KARTAL Hasan Basri BASAGA 《Water Science and Engineering》 EI CAS 2009年第1期43-57,共15页
This study presents earthquake performance analysis of the Torul Concrete-Faced Rockfill (CFR) Dam with two-dimensional dam-soil and dam-soil-reservoir finite element models. The Lagrangian approach was used with fl... This study presents earthquake performance analysis of the Torul Concrete-Faced Rockfill (CFR) Dam with two-dimensional dam-soil and dam-soil-reservoir finite element models. The Lagrangian approach was used with fluid elements to model impounded water. The interface elements were used to simulate the slippage between the concrete face slab and the rockfill. The horizontal component of the 1992 Erzincan earthquake, with a peak ground acceleration of 0.515g, was considered in time-history analysis. The Drucker-Prager model was preferred in nonlinear analysis of the concrete slab, rockfill and foundation soil. The maximum principal stresses and the maximum displacements in two opposite directions were compared by the height of the concrete slab according to linear time-history analysis to reveal the effect of reservoir water. The changes of critical displacements and principal stresses with time are also shown in this paper. According to linear and nonlinear time-history analysis, the effect of the reservoir water on the earthquake performance of the Torul CFR Dam was investigated and the possible damage situation was examined. The results show that the hydrodynamic pressure of reservoir water leads to an increase in the maximum displacements and principal stresses of the dam and reduces the earthquake performance of the dam. Although the linear time-history analysis demonstrates that the earthquake causes a momentous damage to the concrete slab of the Torul CFR Dam, the nonlinear time-history analysis shows that no evident damage occurs in either reservoir case. 展开更多
关键词 earthquake performance evaluation concrete-faced rockfill dam dam-soil-reservoir interaction Drucker-Prager model interface element Lagrangian approach nonlinear time-history analysis
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Impacts of Agricultural Non-point Pollution on Water-source Area in Songhua Dam 被引量:2
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作者 钟萍 段宗亮 《Agricultural Science & Technology》 CAS 2012年第11期2375-2378,共4页
[Objective] The aim was to research impacts of agricultural non-point pol- lution on water-source region in Songhua Dam, laying foundation for control of water pollution and scientific protection of water-source regio... [Objective] The aim was to research impacts of agricultural non-point pol- lution on water-source region in Songhua Dam, laying foundation for control of water pollution and scientific protection of water-source region. [Method] Water in Muyang River, lengshui River and Zizania aquatica region were sampled to measure content of pollutants in water and conclude relation between water contamination and agri- cultural non-point pollution to find the major cause of pollution. [Result] Organic pollu- tant in Muyang River was higher; N and P contents in Lengshui River were higher; the measured indices in Zizania aquatica region excessively exceeded related stan- dard. [Conclusion] The chemical fertilizers and pesticides are the toxic materials lead- ing to water contamination and constitute a major cause of pollution in Songhua Dam water-source region. Agricultural non-point pollution should be controlled in a scientific way. 展开更多
关键词 Songhua dam reservoir Water-source region Agricultural non-pointpollution
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基于GeoDam-BREACH与Graham法的溃坝生命损失估算 被引量:5
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作者 傅志敏 杜汶桐 +1 位作者 孟颖 王志刚 《水利水运工程学报》 CSCD 北大核心 2019年第2期93-98,共6页
应用GeoDam-BREACH工具包模拟了超标准洪水状况下小井沟水库下游的溃坝洪水演进过程,得到水库溃坝下游淹没范围与淹没区水深分布,然后采用Graham法对溃坝导致的生命损失风险进行分析。分析结果表明,小井沟水库发生漫顶破坏时,溃坝洪水... 应用GeoDam-BREACH工具包模拟了超标准洪水状况下小井沟水库下游的溃坝洪水演进过程,得到水库溃坝下游淹没范围与淹没区水深分布,然后采用Graham法对溃坝导致的生命损失风险进行分析。分析结果表明,小井沟水库发生漫顶破坏时,溃坝洪水对下游产生严重影响,下游村镇有受淹风险;下游溃坝淹没区域的风险人口死亡率较高,并且随着警报时间的减小而增大,从而得出警报时间和风险人口对溃坝洪水严重性的理解程度是生命损失的重要影响因素、应当加强水库大坝的日常巡查工作和预警系统的结论。研究成果为小井沟水库的防洪调度和应急预案编制提供了有效支持,对于同类水库的防洪和安全管理亦具有参考价值。 展开更多
关键词 溃坝 生命损失估算 Geodam-BREACH Graham法 小井沟水库
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Multiphase Flow Simulations through Tarbela Dam Spillways and Tunnels 被引量:3
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作者 Muhammad Abid Muftooh Ur Rehman Siddiqi 《Journal of Water Resource and Protection》 2010年第6期532-539,共8页
Tarbela dam is one of the largest earth filled dam in the world used for power generation and irrigation purposes. Like all reservoirs the sediments inflow in the Tarbela reservoir has resulted in reduction in water s... Tarbela dam is one of the largest earth filled dam in the world used for power generation and irrigation purposes. Like all reservoirs the sediments inflow in the Tarbela reservoir has resulted in reduction in water storage capacity and is also causing damage to the tunnels, power generating units and ultimately to the plant equipment. This numerical study was performed to predict the flow patterns and characteristics in Tarbela dam. Tunnel 3 and 4 inlets;originally on the bed level were raised in the 3-D model and meshed. Analysis was performed using multiphase flow (water and air) for maximum inflow in the reservoir, i.e., considering summer season and discharging water through different locations, i.e., tunnels and spillways. Pressure, velocities, flow rate and free surface height results obtained were found in good agreement with the analytical and existing results where available. Results show uneven discharge through each gate due to maximum velocity near exits and overall stagnant phenomena of water within the reservoir. Maximum velocity was observed along the spillways outlet. Strong vortex motion was observed near the spillways outlet and tunnel inlets. New design of Tunnel 3 and 4 were suggested to WAPDA in order to decrease the sediment inflow and improvements in design of the spillways were suggested. 展开更多
关键词 Tarbela dam reservoir FLOW Simulation MULTIPHASE FLOW SPILLWAYS TUNNELS
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Spatial characters of nutrients in Wujiangdu Reservoir in karst river,SW China 被引量:1
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作者 Jun Zhu Siliang Li +3 位作者 Yuchun Wang Haiyu Yan Limin Liao Jun Zhong 《Acta Geochimica》 EI CAS CSCD 2017年第4期605-610,共6页
A preliminary assessment of the Wujiangdu Reservoir examined nutrient distribution and transport.Water samples were collected in the summer(July) of 2004, during the high-flow season. Inorganic nutrients(N,P, Si) and ... A preliminary assessment of the Wujiangdu Reservoir examined nutrient distribution and transport.Water samples were collected in the summer(July) of 2004, during the high-flow season. Inorganic nutrients(N,P, Si) and chlorophyll a(chl a) concentrations of the Wujiangdu Reservoir and its inflow rivers were analyzed.Other water parameters(dissolved oxygen, p H, temperature, and electrical conductivity) were measured as well.The results show gradually decreasing concentrations of NO_3^--N and dissolved silicate in the surface water moving downstream to the dam of the Wujiangdu Reservoir.Additionally, soluble reactive phosphorus concentrations measured very low, with most falling below the sensitivity threshold of the method used in surface waters. Particulate phosphorus and NO_3^--N were the predominant species of phosphorus and nitrogen in the reservoir, respectively. The concentration of nutrients in the Yeji River was the largest of all inflow rivers. The maximum concentration of chl a was found near the dam. These results reflect upstream conditions similar to that of a river, and reservoir conditions near the dam similar to that of a natural lake system. 展开更多
关键词 Wujiangdu reservoir Nutrients distribution characteristics dam
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Stress-strain analysis of Aikou rockfill dam with asphalt-concrete core 被引量:1
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作者 Chaoyang Fang, Zhenzhen Liu State Key Laboratory of Water Resources and Hydropower Engineering Sciences, Wuhan University, Wuhan, 430072, China 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第2期186-192,共7页
Aikou rockfill dam with asphalt-concrete core is situated in a karst area in Chongqing City, China. In order to study the operative conditions of the rockfill dam, especially those of the asphalt-concrete core, the Du... Aikou rockfill dam with asphalt-concrete core is situated in a karst area in Chongqing City, China. In order to study the operative conditions of the rockfill dam, especially those of the asphalt-concrete core, the Duncan model is adopted to compute the stress and strain of both the rockfill dam and the asphalt-concrete core after karst grouting and other treatments. The results indicate that the complicated stress and deformation of both the dam body and the core are within reasonable ranges. It is shown that structure design and foundation treatment of the dam are feasible and can be used as a reference for other similar projects. 展开更多
关键词 asphalt-concrete core rockfill dam Aikou reservoir stress and deformation
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Damming effect on the distribution of mercury in Wujiang River 被引量:4
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作者 蒋红梅 冯新斌 戴前进 《Chinese Journal Of Geochemistry》 EI CAS 2005年第2期179-183,共5页
Seasonal changes in total mercury concentrations in surface water were observed for the Wujiang River, with higher values at the time of greater flow. The total mercury in this river was mostly associated with suspend... Seasonal changes in total mercury concentrations in surface water were observed for the Wujiang River, with higher values at the time of greater flow. The total mercury in this river was mostly associated with suspended particles, particulate mercury accounting for 84% of the total mercury flux on average during the high flow period, and 52% of the total mercury flux on average in the low flow period. Significant losses of Hg from the water were observed in the downstreams of the reservoir. In addition, the concentrations of particulate mercury in the downstreams of reservoir appeared to have been enhanced by sediment re-suspension and shoreline erosion caused by flood discharge, while the filtered portion decreased. These observations suggested that reservoirs played an important role in controlling the transport and fate of mercury in the Wujiang River. 展开更多
关键词 堰塞效应 乌江河 化学污染 水库治理
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