CONTENTS[Chinese]
These
Elevation of Tongguan,Sedimentation of the Lower Weihe River and the Sanmenxia Project ZHOU Wen-hao,CHEN Jian-guo,LI Hui-mei
For Resolution of Successive Sedimentation and Flood-water Logging Disasters in the Area Upstream Dongguan,the Sanmenxia Project Needs to be Further Reconstructed ZENG Qing-hua
Near-Bed Velocity Profiles in Blown-Sand Flow NI Jin-ren,LI Zhen-shan
A Preliminary Study on the Formula of Non-uniform Sediment Carrying Capacity YU Ming-hui,YANG Guo-lu,LIN Gao-feng,LIU Jian-jun
Short articles
Research of the Mathematical Model and Analysis to Regulation Engineering Measures of Jiepai Reaches in the Transition Segment CHEN Xiao-yun,GAO Kai-chun
Effects of Organic Matter on Flocculation and Settling Properties of Fine Sediment in Still Water CHEN Hong-song,SHAO Ming-an
Study on Circular Jet Scouring Loose Sediment Deposited over the Outlet LIU Cheng,HE Yun,WEI He-ping
MCGS's Configuration Software and Its Application in Large-Scale River Model Experiment YU Bang-yi,WU Feng,MA Hao
Characteristics of Sediment Outflow and Analysis of the Runoff Needed by Sediment Outflow in the Lower Yellow River YIN Guo-kang
Formation Analysis and Regulation Plan for Dredging Channel of the Three Sand Shoals(Fujiang Sand Shoal,Tongzhou Sand Shoal and Baimao Sand Shoal)on the Lower Yangtze River XIA Yun-feng,CAO Ming-xiong,CHEN Xiong-bo
Analysis of Yellow River Flood Characteristics in Zhengzhou SHI Zhong-wei,LIU Tian-cai,YANG Ling
Study on the length and Maximum Width of the Circulating Region Caused by a Dike LI GUO-bin,HAN Xin,FU Jin-xian
Review
Study on the Fluid Mud in the Yangtze Estuary XU Jian-yi,YUAN Jian-zhong

Elevation of Tongguan,Sedimentation of the Lower Weihe River and the Sanmenxia Project

ZHOU Wen-hao, CHEN Jian-guo, LI Hui-mei
(China Institute of Water Resources and Hydropower Research)

Abstract: The Sanmenxia project has been founded for 40 years.The elevation at Tongguan,a datum point of the Lower Weihe River with a distance of 113km from the Sanmenxia dam,was raised by 5.2m in the first 4 years because of tremendous deposition. The serious depositionalso occurred correspondingly on the Lower Weihe River.The project was forced to complete two reconstructions and change the operation mode of the reservoir.Up to now,the deposition on the Lower Weihe River has reached to 13.19×108m3,which severely threatens the safety of the ancient capital Xian and the wide area along the Lower Weihe River.This paper points out that main reasons affecting the raising of Tongguan elevation. This paper also submits the proposals of the measures to lower the elevation of Tongguan and alleviate the deposition on the Lower Weihe River.

Key words: elevation at Tongguan;datum point of erosion; mode of reservoir operation; retrogressive erosion; erosion along the river

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For Resolution of Successive Sedimentation and
Flood-water Logging Disasters in the Area Upstream Dongguan,
the Sanmenxia Projcet Needs to be Further Reconstructed

ZENG Qing-hua
(China Institute of water Resources and Hydropower Research)

Abstract: This paper reminisces premier Zhou's profound concern and his strategic decision, reviews the experience and lessons in the construction and operation of the Sanmenxia reservoir,analyses the serious influence broughtby the reservoir deposition in the area upstream of Tongguan,a constrained gorge reach, and points out that the sedimentation in the confluence area of the Yellow River, the Weihe and the Beiluo River has not been essentially changed,althoughthe project has been forced to be completed two times of reconstruction, the channel elevation at Tongguan was 328.6m in 1996,5.2m higher than that before the reservoir was founded.The cross-sectional area of flow of Tongguan now is equal to 1/3 of the section as it was before.The tremendous deposition and its retrogressive extension occurred on the Weihe and the Beiluo River and the main stream of the Yellow River,because of the constrain effects of Tongguan gorge and raising of local erosionbase.The total deposition along the Lower Weihe River reached to 12.7×108m3 in the period from the beginning of reservoir operation to 1995.The Weihe River has been become a socalled “up-ground” river.This paper proposes to further reconstruct the Sanmenxia Project in order to increase the flood-dischargingcapacity,lower the elevation of river bed at Tongguan,resolve the sediment deposition and flood-waterlogging disaster in the Lower Weihe River, and to make contribution to the great development of western China.

Key words: Sanmenxia reservoir; sediment deposition; engineeringproject of reconstruction

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Near-Bed Velocity Profiles in Blown Sand Flow

NI Jin ren1,2,LI Zhen shan2,3
(1.Center for Environmental Sciences, Peking University, 2.The Key Laboratory of Water and Sediment Sciences, Ministry
of Education, China; 3.Department of Hydraulic Engineering, Tsinghua University)

Abstract: The distribution of wind velocities with height during saltation is discussed at length based on both the data from authors' wind tunnel experiments, in which the relative complete measurements of the parameters related to the wind velocities were made, and existing data from others' experiments. Theoretical analyses were made for the fluid shear stress within the saltation layer, which was found depending on the threshold shear velocity, the variations of vertical velocity of grains with height, and the vertical distribution of the mass flux of grains. As a result, an analytical expression for the wind velocity profile during saltation was developed and the predicted results were in good agreement with the experimental data. It was indicated that Bagnold's view that the wind velocity profiles for different wind strengths during saltation converge to a focusis correct, but that the focus is not always transition from profiles within the saltation layer to ones outside of the saltation layer. The more reasonable transition was found, the height of which scaled with 0.015 times of the second powerof the fluid shear velocity above the saltation layer. The equation given by Owen for the wind velocity profile outside the saltation layer is sound, but if the coefficient, C= 0.04 in the dynamic roughness formulae, it is more consistent with experimental data. For a given free stream velocity, the air friction velocities during saltation are larger than the equivalent clean air friction velocities。Air kinetic energy loss due to grain movement reaches the maximum at some height near the bed surface while the rate of air energy loss monotonically declineswith height above the bed.

Key words: wind velocity profile; near bed region; kinetic energy loss; shear velocity; wind tunnel experiment

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A Preliminary Study on the Formula of Non-uniform Sediment Carrying Capacity

YU Ming hui1， YANG Guo lu1， LIU Gao feng2，LIU Jian jun1
(1.Hydraulic and Eletric Institute　2.East China Normal University)

Abstract: In this paper, a new formula of non uniform sediment carrying capacity has been built.Based on summing up ancient research, the hypothesis of “turbulence restrict" and the theory of energy balance, considering factors that influence the sand carrying capacity such as the condition of incoming sediment and flow, the comparative viscosity of sediment-laden flow and the bed material grade, introducingtwo parameters to reflect the viscosity and degree of non uniform, a set of formula of sediment carrying capacity has been set up.Natural field data has been used to calibrate it's coefficient . The formula hasbeen tested and shown reasonable. It fits to both ordinary sediment ooncentration and hyperconcentrated sediment flow.

Key words: non uniform sand；sediment carrying capacity；the coefficient of comparative viscosity；bed material grade

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Research of the Mathematical Model and Analysis to Regulation Engineering Measures of
Jiepai Reaches in the Transition Segment

CHEN Xiao yun，GAO Kai chun
(Changjiang River Waterway Bureau)

Abstract: A mathematical model and analysis is applied to simulate the channel regulation engineering measures of Jiepai reaches in the transition segment. The model has been finished according to the water-sediment characteristics of Jiepai reaches on the Middle Yangtze River. The research achievements be submitted including erosion and deposition volume, navigation channel change, velocity distribution, current regime in calculation stretch after channel regulation, are useful to design.

Key words: Jiepai reaches; mathematical model

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Effects of Organic Matter on Flocculation and Settling Properties of Fine Sediment in Still Water

CHEN Hong song， SHAO Ming-an
(State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of
Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources)

Abstract: Sediment concentration of 10 g/L is prepared in 1000ml cylinder which contains CaCl2 and MgCl2 solutions with concentration ranging from 0 to 1.0mmol/L, and the relative sediment concentration at the depth of 20cm below suspension surface is measured with a 20-ml pipette in this paper. The results showed thatsediment concentration at the same depth decreases exponentially with settling time in still water, and the change of sediment concentration with time is independent of organic matter content. However, when organic matter is removed by H2O2,optimal electrolyte concentration for fine sediment flocculation becomes lower, and fine sediment settles faster with the obvious increase of .

Key words: CaCl2；MgCl2；organic matter；fine sediment；flocculation and settling properties

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Study on Circular Jet Scouring Loose Sediment Deposited over the Outlet

LIU Cheng１，HE Yun１，WEI He ping2
(1.International Research & Training Center on Erosion & Sedimentation　
2.Anhui Architectural Engineering Institute)

Abstract: Related to the studying on the sea outfall engineering of city sewage disposal, circular jet scouring the loose sediment deposited over the outlet is studied through hydraulic model tests. The processes of jet scouring deposited sediment can be divided into three stages according to the experiment, that are stages of initial fluidization, full fluidization and stable and clear scouring pit. Using dimension analysis and regresion analysis to the experimental data, the empirical equations to predict the critical sediment scouring velocity and the dimensions of scouring pit of which horizontal circular jet scouring loose sediment deposited over the outlet in the stagnant water are put forward.

Key words: jet；scouring；sediment；hydraulic model

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MCGS's Configuration Software and Its Application in Large-Scale River Model Experiment

YU Bang yi1, 2，WU Feng2，MA Hao2
(1. College of Water Conservancy and Hydropower Engineering, Hehai University
2. Anhui & Huaihe River Water Resources Research Institute).

Abstract: For the first, Configuration Monitoring Software is applied in the automated measure and control system developed for the large-scale river model experiments of Huaihe River main stream from Zhengyangguan to Tianjiaan, and very good effect is obtained. According to the developing work of the automated measureand control system for the model, the property of MCGS's Configuration Monitoring Software and its second development and application are concisely introduced in this paper.

Key words: configuration monitoring software; river model experiment; automated measure and control; second development and applicationLM

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Characteristics of Sediment Outflow and Analysis of the
RunoffNeeded by Sediment Outflow in the Lower Yellow River

YIN Guo-kang
(Department of Geo. and Ocean Sciences)

Abstract: The main points of this paper are as follows:

　　1. The lower Yellow River is a known aggrading river, in which about three-quarters of the oncoming sediment were exported, and the rest was deposited on the channel since 1950. On the other hand, it is a river with grading tendency, whichhas a strong self-adjusting function. So the degradation almost arises every year and the degradation stage usually occurs in Mar., Apr. and from Sept. to Oct.

　　2. For exception the period 1960～1973, that is early in putting the Sanmenxia reservior into operation, the sediment quantity of inflow or outflow of flood period accounted for over 85% of the annual total in the lower Yellow River since 1950. And the intensity of sediment outflow is generally small during the degradation. Therefore it is very important for decreasing channel deposition to seize flood opportunity to release sediment.

　　3. After aggradation over a period of years, the lower Yellow River presented the degradation for a few years running such as 1983～1984 with plentiful runoff.It is an incarnation of self-adjusting behaviour of the aggrading river for tending to balance with longer temporal scale.

　　4. The analogue of process of sediment outflow on the Lijin station, the reach of the Yellow River mouth, manifested that annual runoff being equal, the difference of annual sediment outflow may be in excess of 100 percent due to difference of runoff process. So it is necessary for the channel tending to steady state to use reservir artificial flood peak to release sediment.

　　5. The annual sediment outflow of the lower Yellow River depends on both annual runoff and sediment load and their processes, on both tendency and strength of hannel self-adjustment. For example, the runoff needed by releasing per ton of sediment was only 20m 3in 1959, owing to rich on-coming sedimnet and concentration of runoff process in this year. And the corresponding runoff was over 110 m3 in 1987, owing to poor on-coming flow and sediment. As to 1965, the firstyear after the operational mode of the Sanmenxia reservior just changed from storing water and retaining sediment to storing clear water and releasing the muddy, the runoff needed by releasing per ton of sediment amounted to 88 m3, owing to serious depositon of river channel. On the average the runoff needed by releasing per ton of sediment was about 36 m3 in the 1950's.

　　6. The analogue of process of runoff-sediment outflow indicated: If western line project of water deversion from the Yangtze River into the Yellow River is accomplished, the annual runoff of the Yellow River flowing into sea may be over 500×108m3 and the channel of its lower reach due to heavy scour will change from the suspended river to a normal one.

Key words: lower Yellow River; capability of sediment outflow; runoff

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Formation Analysis and Regulation Plan for Dredging Channel of the Three Sand Shoals
(Fujiang Sand Shoal,Tongzhou Sand Shoal and Baimao Sand Shoal)on the Lower Yangtze River

XIA Yun-feng, CAO Ming-xiong, CHEN Xiong-bo
(Nanjing Hydraulic Research Institute)

Abstract: The three sand shoals (Fujiang sand shoal,Tongzhou sand shoal and Baimao sand shoal) waterway on the lower Yangtze River are important obstacles for their shallow water depth to the month of that river.Along with the practicing of channel regulation of the month and utilizing the so-called “gold waterway” of the Yangtze River effectively,it is urgently to regulate the three sand shoals.In this paper,river evolvment of Jiangyin-Liuhekou watercourse where three sand shoal lain are analyzed,several main factors which effected those shoals are discussed integrated with the characteristics of reiver physical parameters and sand movement.The tendency to the waterway and the influence of the channel in the future are discussed.Based on these analyses a original plan is put foward to regulate these shoals to mett the need of the entrance of ocean going vessel.

Key words: formation analysis; channel regulation; Tongzhou sand shoal; Fujiang sand shoal; Baimao sand shoal

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Analysis of Yellow River Flood Characteristics in Zhengzhou

SHI Zhong-wei, LIU Tian-cai, YANG Ling
(Zhengzhou Bureau,YRCC)

Abstract: In Zhengzhou, Yellow River floods from different sources have different characteristics; in the course of flood running, interaction effect occurs between the flood and river bed, and sediment exchange also occurs between water flow, river bed, flood plain and main channel; construction of production dyke changes the advancing regular pattern of the flood; travel time and water level of flood are affected by various factors; the flood carrying hyperconcentrated sediment which brings serious threat to flood control projects has its outstanding characteristics; flood forecasting is a deep, detailed and complicated work, and hydrological data of the Yellow River flood should be open to the experts and scholars within and outside the Yellow River basin.

Key words: flood control; river channel; flood; sediment; forecasting; Yellow River in Zhengzhou

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Study on the Length and Maximum Width of the Circulating Region Caused by a Dike

LI Guo-bin1, HAN Xin1,FU Jin-xian2
(1.Nanjing Hydraulic Research Institute 2.Jiangsu Hydraulic Engineering Construction Bureau)

Abstract: In this paper,based on 2-D depth averaged water flow difference equations and using some assumptions which are different from ones made by other researchers on turbulence viscous stress\,main flow velocity distribution laterally,turbulence viscous coefficient,the formula used to compute the length and maximum width of the circulating flow are derived.The computation resultsare in reasonable agreement with experiment data.The research results indicate that the length of circulating flow varies with the dike length,depth,roughness,area contraction ratio,river width contraction ratio and the maximum circulatingwidth varies with the river width,area contraction ratio and river width contraction ratio.The width contraction ratio equals to the area contraction ratio only for the channel and they are different from each other for the natural river.

Key words: dike; cirulating flow length； maximum circulating width；area contraction ratio；width contraction ratio

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Study on the Fluid Mud in the Yangtze Estuary

XU Jian-yi, YUAN Jian-zhong
(Shanghai Investigation、Design and Research Institute)

Abstract: Generally there is a higher sediment deposit rate in the navigation channel on muddy coasts so that the constant dredge is necessary, which usually cost more in the expenditure of the port operation in those areas. In order to reduce the dredge cost, it is important to study the nautical depth, namely to determine the critical unit weight of mud that is navigable. The deep waterway regulation works is now in construction in the Yangtze Estuary. It is important to study the characteristics and variation of fluid mud in the Yangtze Estuary. Thispaper deals with all the aspects of fluid mud in the Yangtze Estuary, including the characteristics、forming conditions and variation、nautical depth, especially analysising the possiblity of fluid mud formation in the North Passage of the Yangtze Estuary. It concludes that fluid mud may be appear in the North Passage after construction of deep waterway regulation works.

Key words: Yangtze Estuary; fluid mud; deep waterway regulation; nautical dept

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