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Science china(Technological Sciences) 2009年第2期52卷 387-391页

作者： LI RuiJie1,2, LUO Feng2 & ZHU WenJin3 1 Key Laboratory of Coastal Disaster and Defence (hohai university), Ministry of Education, nanjing 210098, china 2 Laboratory of Marine Environment, hohai university, nanjing 210098, china 3 Institute of Physical Oceanography, hohai university, nanjing 210098, china Key Laboratory of Coastal Disaster and Defence (hohai university) Ministry of Education Nanjing China Laboratory of Marine Environment Hohai University Nanjing China Institute of Physical Oceanography Hohai University Nanjing China

The suspended sediment transport equation and its near-bed sediment flux are one of the key problems of sediment transport research under nonequilibrium condition. Based on the three-dimensional primitive suspended transport equation, the two-dimensional suspended sediment transport equation is deduced. The derived process indicates that the physical essence of the near-bed sediment flux is right the bottom boundary condition for the suspended sediment transport equation. This paper analyzes the internal relations between the two methods of sediment carrying capacity and shear stress in common use, points out the consistency of these two methods in terms of form and physical meaning, and unifies these two methods theoretically. Furthermore, based on the analysis and comparison of the expressions of the near-bed sediment flux, this paper summarizes some problems to which attention should be paid, thus offering a novel approach to the study and the solution of the problems of suspended sediment transport and exchange flux of near-bed water sediment.

关键词： suspended sediment transport equation near-bed sediment flux sediment carrying capacity shear stress

MODELING OF WATER DYNAMICS AND POLLUTANT SPREADING IN THE LUOMAHU RESERVOIR FOR WATER TRANSFER FORM SOUTH TO NORTH OF china

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Journal of Hydrodynamics 2001年第4期13卷 14-23页

作者： Wang Chao College of Water Resources and Environment, hohai university, nanjing 210098, china Coll. of Water Resources Hohai Univ. Nanjing 210098 China

Water quality is the key problem of the East-Line Project of Water Transfer from South to North china. In this paper, the principles of a 1D and 2D-integrated mathematical model for describing the dynamics of water in a flow-through river, canals and lakes was worked out. The numerical method and model algorithm were developed. The efficiency of the model was estimated by applying it to studying water dynamics in the Luomahu reservoir and simulating the spreading process of a polluted water mass and the evolution of the concentration. The results of calculations are used to assess water environmental quality and to manage water resource in the Luomahu reservoir and the Jinghang-Canal for the Project of Water Transfer from South to North china.

关键词： mathematical model integral stream function water quality Water Transfer from South to North Project

The Shannon capacity of a communication channel,graph Ramsey number and a conjecture of Erds

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Chinese Science Bulletin 2001年第24期46卷 2025-2028页

作者： LI YushengCollege of Sciences, hohai university, nanjing 210098, china College of Sciences Hohai University Nanjing China

We briefly introduce the connection between the Shannon capacity of a communication channel and graph Ramsey number, which may receive attention from researchers on communication theory and graph theory.

关键词： communication channel Shannon capacity Ramsey number.

EFFECTS OF SUBMERGED MACROPHYTES ON SEDIMENT SUSPENSION AND NH_4-N RELEASE UNDER HYDRODYNAMIC CONDITIONS

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Journal of Hydrodynamics 2010年第6期22卷 810-815页

作者： WANG Chao WANG Cun WANG Ze Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of EducationHohai University Nanjing 210098 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing210098 China College of Mechanics and Materials Hohai University Nanjing 210098 China

Aquatic vegetation affects sediment suspension and nutrient release by changing the flow structure. Experiments on the influence of submerged vegetation on flow structure, sediment suspension, and NH4-N release were carried in a flume with natural submerged vegetation. Turbulence characteristics in the vegetation section were measured using a three-dimensional acoustic Doppler velocimeter. The effects of submerged vegetation on bed shear stress （ τb ）, sediment suspension, and NH4-N release were analyzed. Results show that with vegetation, bed shear stress is reduced by about 20% - 80%, which, in turn, reduces sediment suspension. The impact of submerged vegetation on sediment suspension and NH4-N release should be considered along with flow intensity. When the flow Reynolds number is relatively small, the submerged vegetation is quite capable of inhibiting sediment suspension and reducing NH4-N release, but when the Reynolds number reaches a certain value, the presence of aquatic plants exacerbates sediment suspension and promotes NH4-N release. Results also reveal that a highly significant positive correlation exists between NH4-N concentration and water turbidity in both vegetated and non-vegetated channels.

关键词： sediment suspension submerged macrophytes turbulence behavior bed shear stress turbidity

Theory and methods of global stability analysis for high arch dam

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Science china(Technological Sciences) 2011年第S1期54卷 9-17页

作者： REN QingWen 1,LI Qiang 1,JIANG YaZhou 2 & JIANG XiaoLan 3 1 Department of Engineering Mechanics,hohai university,nanjing 210098,china 2 College of Water Conservation and Hydropower Engineering,hohai university,nanjing 210098,china 3 Changjiang Academy of Sciences,Wuhan 430010,china Department of Engineering Mechanics Hohai University Nanjing China College of Water Conservation and Hydropower Engineering Hohai University Nanjing China Changjiang Academy of Sciences Wuhan China

The global stability of high arch dam is one of the key problems in the safety study of arch dams,but no feasible method with theoretical basis is *** this paper,based on the stability theory of mechanical system,it is demonstrated that the global failure of high arch dams belongs to a physical instability starting from local strength failure,which is the extreme point instability according to the characteristics of load-displacement curve obtained from the failure process of dam-foundation system. So the global failure of dam-foundation system should be studied with the stability theory of mechanical *** is also pointed out that the current stability analysis methods used in engineering are consistent with the stability theory,but not established according to the mechanical system stability theory directly.A perfect method can be obtained through the study of physical disturbance equations.

关键词： high arch dam global stability physical instability extreme point instability

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 Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University Nanjing China Geotechnical Research Institute Hohai University Nanjing China Department of Civil Engineering Ryerson University Toronto Canada Department of Geotechnical Engineering Nanjing Hydraulic Research Institute Nanjing 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

RISK ANALYSIS OF EROSION BELOW THE DAM OF ER TEN PROJECT

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Journal of Hydrodynamics 1991年第3期3卷 19-25页

作者： Xu Zu-xin Guo Zi-zhong, hohai university, nanjing 210024, P.R.china Hakai Univ Nanjing China

The erosion risk below the dam of Er Tan project, which comes from the flood relief of the spillway and mid- dle outlet spillway, is analysed by risk analysis theory. According to the analysis results, it is imperative that the stilling pool below the dam should be adopted to protect river bed from erosion. From the view of risk-protection and economy, the Er Tan project design scheme that adopted the stilling pool is coincident with safe and economical rules. It is efficient and scientific. The erosion risk analysis method used in the paper can be used in other projects. The results are certainly of reference value and great significance for engineering design.

关键词： RISK ANALYSIS OF EROSION BELOW THE DAM OF ER TEN PROJECT ER

THE ALGORITHMS AND APPLICATIONS FOR DETERMINING PERMEABILITY COEFFICIENTS BY PULSE SPECTRUM TECHNIQUE

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Journal of Hydrodynamics 2002年第2期14卷 112-115页

作者： Wang Ling-ling College of Water Conservancy and Hydropower Engineering, hohai university, nanjing 210098, china Coll. of Water Conservancy Hohai Univ. Nanjing 210098 China

The determination of inhomogeneous permeability coefficient was studied as a parameter-control inverse problem for parabolic-type equation in this paper. By virtue of PST, the solution of the inverse problem is converted into an iteration procedure of solving a direct problem and solving a Fredholm integral equation of the first kind. Besides, Tikhonov normalization method is introduced to treat the uncertainty caused by the integral equation. Thus an algorithm for determining inhomogeneous permeability coefficient has been formulated and implemented. Numerical results show: (1) The algorithm presented in the paper is suitable to strongly inhomogeneous seepagel; (2) The additional information needed for solution is merely the seepage velocity on partical boundary, so that drill works can be reduced remarkably; (3) The algorithm is applicable to determining inhomogeneous transmission coefficients in groundwater engineering or other engineering.

关键词： inverse problem Pulse Spectrum Technique (PST) permeability coefficient parameter identification

COMPOSITE MODELING APPROACH AND EXPERIMENTAL STUDY FOR SUBSURFACE TRANSPORT OF CONTAMINANTS FROM LAND-DISPOSAL SITES

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Journal of Hydrodynamics 2003年第4期15卷 1-9页

作者： Wang Chao, Wang Pei-fang, Li Yong Department of Environmental Engineering, hohai university, nanjing 210098, china Dept. of Environ. Eng. Hohai Univ. Nanjing 210098 China

A composite modeling approach was presented for simulating thethree-dimensional (3-D) subsurface transport of dissolved contaminants with transformation *** approach was based on vertical infiltration and contaminant transport in the unsaturated zoneand 3-D groundwater flow and contaminant migration in the saturated zone. Moisture movement andgroundwater flow were considered to be steady, but contaminant transport was treated as continuousand transient. The transformed unsaturated zone and saturated zone transport equations were solvednumerically with different techniques. The model contains a 3-D solution to flow and transport inthe saturated zone, as well as two-dimensional solutions to vertical cross-sectional and arealscenarios. In order to verify the composite modeling, extensive experiments were conducted in twolarge-scale variable-slope soil tanks of 1200cm in length, 150cm in width and 150cm in height. Sandsoil was filled in the tank as the porous media. The solutions of KBr or NH_4C1 were introduced intoeach soil tank from 80 X 37cm^2 area sources located on the top of the porous medium. Results fromnumerical simulations were compared with the data from tests. Predicted results are in goodagreement with the experimental data.

关键词： composite modeling groundater flow finite element model experiment