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STUDY OF NAVIGATION CHANNEL IMPROVEMENT AT WENZHOU AND YANGFUSHAN PORTS

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China Ocean engineering 1990年第1期5卷 65-80页

作者： li Haolin senior engineer, River and Harbor Division, nanjing hydraulic research institute, nanjing nanjing hydraulic research Inst Nanjing China

The paper gives a brief description of the causes of shoaling, guidelines for regulation and layout of the project, and demonstrates the effectiveness of the improvement works using hydrological, sediment, and topogra... 详细信息

关键词： Hydrodynamics Navigation Hydrology

STUDIES ON GREY MODEL DYNAMIC PREDICTION TO CAVITATION DAMAGE OF TURBINES

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Journal of Hydrodynamics 2003年第5期15卷 29-34页

作者： Wu Fu sheng, Tong Zhong shan, li Yun hui nanjing hydraulic research institute, nanjing 210029, China nanjing hydraulic Res. Inst. Nanjing 210029 China

In thus paper, cavitation damage of turbines is firstly analyzed andpredicated from the view point of system engineering by use of the grey system theory. A detaileddescription of modeling, dynamic prediction and accuracy test for the grey system of turbines wasgiven. Two special cases for grey dynamic prediction as well as its accuracy test were *** results fall into the grade I, the accuracy is satisfactory and its prediction requirements canbe met well. It shows that the grey system theory can be employed to predict the cavitation damageof turbines, and it can provide a scientific basis for timely investigation and maintenance ofturbines.

关键词： turbine cavitation damage grey prediction

Back analysis of mechanical parameters of roller compacted concrete dam

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Science China(Technological Sciences) 2010年第3期53卷 848-853页

作者： GU ChongShi 1,2,3,li Bo 1,XU GuangLei 4 &YU Hong 1,2,3 1 State Key Laboratory of Hydrology-Water Resources and hydraulic engineering,Hohai University,nanjing 210098,China 2College of Water Conservancy Hydropower,Hohai University,nanjing 210098,China 3National engineering research Center of Water Resources engineering Safety,Efficient Utilization and nanjing 210098,China 4 nanjing hydraulic research institute,nanjing 210029,China 1. State Key Laboratory of Hydrology-Water Resources and hydraulic engineering Hohai University Nanjing 210098 China2. College of Water Conservancy Hydropower Hohai University Nanjing 210098 China3. National Engineering Research Center of Water Resources Engineering Safety Efficient Utilization and Nanjing Nanjing 210098 China4. Nanjing Hydraulic Research Institute Nanjing 210029 China

In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam *** the process of back analysis,the initial samples of parameters were designed with uniform design ***,a transversely isotropic model of RCCD was established by *** *** this model,training samples of LSSVM model could be *** then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was ***,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using *** inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be *** example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.

关键词： roller compacted concrete dam mechanical parameters back analysis

A new elliptic-parabolic yield surface model revised by an adaptive criterion for granular soils

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Science China(Technological Sciences) 2010年第8期53卷 2152-2159页

作者： liU HanLong 1,2 ,XIAO Yang 1,2 ,liU JinYuan 3 &li GuoYing 4 1 Key Laboratory of Ministry of Education for Geomechanics and Embankment engineering,Hohai University, nanjing 210098,China 2 Geotechnical research institute,Hohai University,nanjing 210098,China 3Department of Civil engineering,Ryerson University,Toronto,Canada 4 Department of Geotechnical engineering,nanjing hydraulic research institute,nanjing 210014,China 1. Key Laboratory of Ministry of Education for Geomechanics and Embankment engineering Hohai University Nanjing 210098 China2. Geotechnical Research Institute Hohai University Nanjing 210098 China3. Department of Civil Engineering Ryerson University Toronto Canada4. Department of Geotechnical Engineering Nanjing Hydraulic Research Institute Nanjing 210014 China

An adaptive criterion for shear yielding as well as shear failure of soils is proposed in this paper to address the fact that most criteria,including the Mohr-Coulomb criterion,the Lade criterion and the Matsuoka-Nakai criterion,cannot agree well with the experimental results when the value of the intermediate principal stress parameter is too *** new criterion can adjust an adaptive parameter based on the experimental results in order to make the theoretical calculations fit the test results more *** original elliptic-parabolic yield surface model can capture both soil contraction and dilation ***,it normally over-predicts the soil strength due to its application of the Extended Mises criterion.A new elliptic-parabolic yield surface mode is presented in this paper,which introduces the adaptive criterion in three-dimensional principal stress *** new model can well model the stress-strain behavior of soils under general stress *** to the original model which can only simulate soil behavior under triaxial compression conditions,the new model can simulate soil behaviors under both triaxial compression conditions and general stress conditions.

关键词： principal stress space intermediate principal stress yield surface failure criterion constitutive model

Properties of Leakage Corrosion of Concrete and Its Durability

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Journal of Wuhan University of Technology(Materials Science) 2008年第6期23卷 946-949页

作者：戈雪良 Department of Materials and Structural engineering Nanjing Hydraulic Research Institute

The properties and mechanism of concrete under water leakage corrosion were studied in terms of the dissolution of calcium oxide and silicon oxide from concrete and the variation of pH value of permeate *** experimental results show that the amount of calcium oxide and silicon oxide dissolved from per cubic meter of concrete gradually decrease with penetration time and ultimately stabilize at a certain *** pH value of permeate water descend along with penetration *** durability of concrete under leakage corrosion was analyzed by a formula fitted on the dissolved amount of calcium oxide.

关键词： concrete leakage corrosion properties durability

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 [a]Ph.D. engineer Department of Sediment research China institute of Water Resources and Hydropower research Chegongzhuangxilu 20 Beijing 100044 China [b]Ph.D. engineer nanjing hydraulic research institute Hujuguanlu 34 nanjing 210024 China [c]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

INFLUENCE OF SEEPAGE FACE OBliQUITY ON DISCHARGE OF GROUNDWATER AND ITS POLLUTANT INTO LAKE FROM A TYPICAL UNCONFINED AQUIFER

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Journal of Hydrodynamics 2007年第6期19卷 756-761页

作者： li Yong WANG Chao YANG lin-zhang li Yi-ping State Key Laboratory of Hydrology-Water Resources and hydraulic engineering Hohai University Nanjing 210098 China College of Environmental Science and engineering Hohai University Nanjing 210098 China institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

Lab experiment and mathematical simulation Modular three dimensional finite difference groundwater （MODFLOW） were performed in a soil tank to simulate the hydrogeochemical interaction between lake and typical unconfined aquifer. Results show that the velocity decreases exponentially with the transect distance on seepage face. The maximal velocity occurs at the top point of seepage face. The obliquity of seepage face has a great influence on the maximum and distribution of seepage velocity. With the increase of the obliquity of seepage face, the maximal velocity decreases quickly and the velocity distribution becomes much more even. Most of groundwater flow and pollutant flux discharges through a narrow portion near the top of seepage face. The flow and mass concentrated in the narrow portion increase with the decrease of the obliquity of seepage face. These will benefit to design a reasonable and economical scenario to manage lakeshore and to control the pollution of lake water near lakeshore.

关键词： shallow lake unconfined aquifer groundwater discharge velocity distribution chloride MODFLOW

^(46)Sc示踪沙核探测器的标定及其应用

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同位素 1993年第1期6卷 21-28页

作者：李樟苏杜效云南京水利科学研究院 210029

叙述了放射性示踪沙探测器的标定过程和结果,其特点是在模拟现埸测量条件的前提下,用硝酸钪溶液制成一个^(46)Sc平面源,用钪玻璃沙制成一块含^(46)Sc的平板源和均匀混合沙层源进行试验。利用^(46)Sc制成的平面源,仔细研究了探测器在不... 详细信息

叙述了放射性示踪沙探测器的标定过程和结果,其特点是在模拟现埸测量条件的前提下,用硝酸钪溶液制成一个^(46)Sc平面源,用钪玻璃沙制成一块含^(46)Sc的平板源和均匀混合沙层源进行试验。利用^(46)Sc制成的平面源,仔细研究了探测器在不同水层厚度复盖条件下,γ射线反散射作用的影响。其标定目的是通过室内模拟研究,测出该探测器的灵敏度因子f_0和水饱和沙对γ射线的线性吸收系数,以便利用计数率平衡法公式计算泥沙运动层厚度。利用^(46)Sc沙制成的平板源和混合沙层源,研究了不同沙层厚度与计数率变化的关系曲线。该关系曲线将作为确定现埸跟踪观测示踪沙回收率的标定曲线。在整理和分析示踪沙扫测资料时,通过计算回收率来评价是否能算出计数率等值线的重心,以便进行输沙率或回淤量的定量计算。

关键词：探测器标定泥沙钪46 示踪沙

ANALYTICAL STUDY OF WAVE MAKING IN A FLUME WITH A PARTIALLY REFLECTING END-WALL

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Journal of Hydrodynamics 2010年第3期22卷 402-409页

作者： ZHOU Bin-zhen NING De-zhi TENG Bin CHEN li-fen State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024China State Key Laboratory of Hydrology-Water Resources and hydraulic engineering Nanjing Hydraulic ResearchInstitute Nanjing 210029 China

Based on the eigenfunction expansion technique, the wave generation by a piston wave maker in a wave flume with a partially reflecting end-wall is studied. The corresponding velocity potential and wave elevation in the flume are obtained. The present analytical solution is verified by the numerical results obtained from a time-domain higher-order boundary element method in a closed flume. Numerical experiments are further carried out to study the difference between the partial/full reflection boundary and the transmission boundary and the effects of the reflection coefficient and the motion period of the wave maker on the wave height. Meanwhile, the natural frequency of the wave flume can be obtained from the analytical expression. The resonance occurs when the motion frequency is equal to the natural frequency. Even the partial reflection of the end-wall in the wave flume experiments has a great influence on the wave height, therefore, inaccurate measurements would be resulted in long-time simulations, especially when the wave frequency approaches the wave flume natural frequency. The present study can serve as a guidance for the physical experiment in wave flumes.

关键词： wave flume wave maker partially reflecting end-wall resonance eigenfunction analytical study