THE OPERATION MODE OF “STORING THE CLEAR WATER AND DISCHARGING THE MUDDY FLOW” FOR RESERVOIRS BUILT ON HEAVILY SILT-LADEN RIVERS——A CASE STUDY OF THE SANMENXIA RESERVOIR     

WenxueLI YuanfengZHANG CuipingZHANG 《国际泥沙研究》2005,20(2):109-116

Observation of the operation of the Sanmenxia Reservoir on the Yellow River has led to the conclusion that to preserve a certain effective storage volume for reservoirs built on heavily silt-laden rivers is feasible if the reservoir is operated according to the principle known as“storing the clear water and discharging the muddy flow”. The relative stability of the bed elevation at the end of the backwater and the reservoir‘s erosion and deposition equilibrium depend on the compatibility of the pool level maintained in non-flood seasons with the conditions of flow and sediment load during flood seasons. Operating the reservoir to regulate the flood and sediment load during flood seasons can reduce the rate ofaggradation in the Lower Yellow River. The basic condition for applying the operation mode of “storing the clear water and discharging the muddy flow” is that a sufficient amount of water should be used for discharging sediment during flood seasons. Under the condition of extremely low flow years, reservoir sedimentation cannot be avoided even if this operation mode is adopted.  相似文献   

A NUMERICAL MODEL OF SEDIMENT TRANSPORT IN HANDUN IRRIGATION DISTRICT     

GAO Jianen  Senior Engineer  North-West Hydro-technical Science Research Institute  Yangling  Shaanxi  China WAN Zhaohui  Professor  China Institute of Water Resources & Hydropower Research  P.O. Box  Beijing . China CHEN Zhicong  Profe 《国际泥沙研究》1997,(3)

LABRIEFINTRODUCTIONOFRANDUNIRRIGATIONDISTRICTYellowRiverisoneofthemainWaterresourcesinNOrthChina.SincethefiftiesirrigationbydivertingwaterfromtheYellowforerdevelOPssteadily.AstheYdlowforerisaheavilysacmentsladenone,sedimentisdiVertedsimultaneouslywhenwaterisdiverted.HOwtoproperlytreatthedivertedsedimentboomesoneOfthekeyproblemsrestrichngthesustainingdevelOPmentofthCwaterresourcesinthatarea.LongchStanceconvopngsedimentisoneofthemainmeasuresfordealingwiththediVertedsedim…  相似文献   

MASS MOVEMENTS AND SEDIMENT TRANSPORT AS A NATURAL HAZARD     

Wolfgang KRON Senior Hydraulic Engineer  Geosciences Research Group  Munich Reinsurance Company  Munich  Germany 《国际泥沙研究》1997,(3)

I.INTRODUCTIONFormillionsofyearswindandwaterhaveshapedtheearth,mountainshavebeenliftedanderodedaway,waterhasevaporatedfromtheoceansandfallenbackonland,rivershaveformedandcarriedwaterandsedanmentfromthemoufltainstotheseas.Someoftherivers--suchastheColoradoRiverintheGrandCanyonregionofNorthAJnerica-foundstablecoursesastheycarvedthemselvesintotheground,others--suchastheYellowhiverinChina-havechangedtheircoursesfrequentlyallthewayintorecenthistory.Itwasonlyafewthousandyearsagothatmanstarte…  相似文献   

EROSION CONTROL AND RESOURCE MANAGEMENT ON UPLAND WATERSHEDS OF GRANITIC REGION     

LIU Xiaoying Senior Engineer  IRTCES  Technical Manager  FAO-FARM Programme OFFICE  P.O. Box  Beijing  China 《国际泥沙研究》1997,(3)

I.FEATURESOFSOILEROSIONINGRANITICREGIONS1.1IntroductionGuangdongProvinceislocatedinsubtropicalzoneandthenorthernborderofthetropicalzone.ThelatitudestCtchesfrom20'07'to25'31'N,thelongitudefrom108'33'tO117'20'E.Subtropicalclimateprevailsinmostoftheprovince.Theannualaveragerainfallis1500-1800mm,withstrongintensityandun-evendistribution.Thedeifyrainfallduringwnhoonstormsmayreach200-300mm:Thetotallandareaisabout178,100sq.km,inwhich25,100sq.kmarecultivated.12,000sq.km,6.7%oftotalP…  相似文献   

皖南—浙西下古生界碳沥青成因及南方海相“有效烃源岩”问题探讨   总被引：2，自引：0，他引：2  

陈安定  黄金明  杨芝文  翟爱军  吴长祥 《海相油气地质》2004,(Z1)

赋存于皖南—浙西的固体碳沥青分为古油藏裂解碳沥青和古油藏破坏次生充填碳沥青两种类型 ,阐明了两类碳沥青的不同成因机制。重新认定了浙西“康山沥青脉”为碳沥青而不是泥岩。论证了皖南、浙西碳沥青的烃源为下寒武统、中—上奥陶统至下志留统、中—上寒武统等。认为加里东运动—广西事件期间是下扬子盆地相区以下寒武统黑页岩为烃源的油藏形成和部分破坏的主要时期。针对南方的油气勘探 ,提出了只有在晚期成藏中作出贡献的源岩才是“有效烃源岩”的新概念。  相似文献   

Gibraltar woman and Neanderthal Man     

Senior Lecturer  EDWARD P.F. ROSE & Merit Researcher  CHRISTOPHER B. STRINGER 《Geology Today》1997,13(5):179-184

Forbes' Quarry, on the Rock of Gibraltar, yielded a human skull in 1848, one of the earliest Neanderthal skeletal remains known to science. Fragments of a second Gibraltar skull, that of a child, were described from Devil's Tower rock shelter in 1928 and have recently been reconstructed and reinterpreted to emphasize the distinction of Homo neanderthalensis from H. sapiens . Neanderthal skeletal remains are confined to Europe, the Middle East and central Asia, their most recent occurrence arguably a refugium in southern Iberia. The race seemingly became extinct about 30 000 years Before Present, for reasons as yet unknown, but a programme of excavations in Gorham's and Vanguard caves on Gibraltar is in progress to elucidate palaeoenvironmental and behavioural changes as some of the last Neanderthals were succeeded stratigraphically by anatomically modern humans with an Upper Palaeolithic culture.  相似文献   

Analytic Solution of Elasto-Plastic Stress in Infinite Slope under Uniform Load     

WANG Nianxiang GU Lei Senior Engineer  Geotechnical Engineering Department  Nanjing Hydraulic Research Institute  Nanjing  P. R. China. Engineer  Plan  Statistics 《中国海洋工程》1999,(2)

-According to the Mohr-Coulomb yield criterion,the stress field of the infinite slope is derivedunder a vertical uniform load q on the top of the slope.It is indicated that elastic and elasto-plastic stateswould occur in the slope.When q is smaller than the critical load,q_p,the slope is in the elastic state.Ifq equals q_p,the slope is in the critical state,and the plastic deformation would occur along the critical an-gle.With the increase of q,the plastic zone would extend,and the slope is in the elasto-plastic state.Ifq equals limit load,the slope is in the limit equilibrium state.The slope may be divided into three zones.Some charts of the critical angle,the critical and limit load coefficients are presented in this paper.  相似文献   

Numerical Model of Total Sediment Transport in the Yangtze Estuary   总被引：2，自引：2，他引：0  

DOU Xiping LI Tilai  DOU Guoren Senior Engineer  River  Harbour Engineering Department  Nanjing Hydraulic Research Institute  Nanjing  P. R. China Senior Engineer  Nanjing Institute of Hydrology  Water Resourses  Nanjing  P. R. China Academician  Nanjing Hydraulic Research Institute  Nanjing  P. R. China 《中国海洋工程》1999,(3)

Based on the non-equilibrium suspended load transport equation,bed load transport equationand sediment transport capacity formulas derived by Dou et al.,a 2-D numerical model of total sedimenttransport in the Yangtze Estuary is presented.In the model,the actions of tidal currents and wind waves andthe effect of salinity on sediment transport are considered.An automatically generated boundary-fitted grid isused to fit the boundaries of the estuary and the boundaries of engineering projects.The verification of calcu-lations shows that the sediment concentration,the deformation of riverbed and siltation in the channels causedby typhoons can be successfully simulated.  相似文献   

A Model for Nonlinear Irregular Waves in Coastal Area     

朱良生  张经汉  李少英 《中国海洋工程》1999,(4)

Based on the refraction-diffraction theory of irregular waves in the waters of slowly-varying cur-rents and depths,and the generation dissipation theory of wind wave,a model for nonlinear irregular wavesin coastal area is developed.In light of the specific conditions of coastal wave character and engineering ap-plication,a practical mathematical model for the nonlinear irregular waves is presented.with directional spec-trum in coastal area.Coast effect,refraction,whitecapping.bottom friction.current,wind and nonlinearaction are considered in this model.The numerical methods and schemes for wave refraction ray,energy con-servation of propagation,energy balance of the generation and dissipation of wind waves have been studied.Finally,the model is used for the directional wave spectrum computation in the Daya Bay.Compared withthe measured data with 956 wave bouys in the Daya Bay,the model results are in good agreement with themeasured results.  相似文献   

Reflection of Short Waves     

Miguel A. LOSADA 《中国海洋工程》1999,(1)

—According to the energy equation,the relation between reflection and energy losses for shortwaves from mild beaches is established and analysed.A reflection coefficient varying with position and en-ergy losses is proposed.Different reflection tests are conducted to check the theoretical analysis.A modi-fied method to estimate the reflection coefficient at varied water depths is suggested based on the linearwave theory.The study indicates that the reflection coefficient from mild beaches has a changing trend forshort waves approaching shoreline.  相似文献