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Erosion-deposition patterns and depo-center movements in branching channels at the near-estuary reach of the Yangtze River

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Frontiers of Earth Science 2020年第3期14卷 537-552页

作者： Boyuan Zhu Jinyun Deng Jinwu Tang Wenjun Yu Alistair G.L.Borthwick Yuanfang Chai Zhaohua Sun Yitian Li School of Hydraulic Engineering Changsha University of Science&TechnologyChangsha410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha410114China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China Changjiang Institute of Survey PlanningDesign and ResearchWuhan430010China Changjiang waterway Institute of Planning Design&ResearchWuhan430040China School of Engineering The University of EdinburghThe King’s BuildingsEdinburghEH93JLUK Department of Earth Sciences Vrije Universiteit AmsterdamBoelelaan 10851081 HVAmsterdamThe Netherlands

Channel evolution and depo-center migrations in braided reaches are significantly influenced by variations in *** study examines the effect of runoff variations on the erosion-deposition patterns and depocenter movements within branching channels of the near-estuary reach of the Yangtze *** assume that variations in annual mean duration days of runoff discharges,ebb partition ratios in branching channels,and the erosional/depositional rates of entire channels and sub-reaches are representative of variations in runoff intensity,flow dynamics in branching channels,and morphological features in the *** results show that the north region of Fujiangsha waterway,the Liuhaisha branch of Rugaosha waterway,the west branch of Tongzhousha waterway,and the west branch of Langshansha waterway experience deposition or reduced erosion under low runoff intensity,and erosion or reduced deposition under high runoff intensity,with the depocenters moving upstream and downstream,*** waterway branches undergo opposite trends in erosion-deposition patterns and depo-center movements as the runoff *** morphological changes may be associated with trends in ebb partition ratio as the runoff discharge rises and *** flattening the intra-annual distribution of runoff discharge,dam construction in the Yangtze Basin has altered the ebb partition ratios in waterway branches,affecting their erosion-deposition patterns and depo-center *** trends are likely to continue into the future due to the succession of large cascade dams under construction along the upper Yangtze and ongoing climate change.

关键词： near-estuary reach Yangtze River runoff discharge ebb partition ratio erosion-deposition pattern depo-center movement

SUPG finite element method based on penalty function for lid-driven cavity flow up to Re = 27500

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Acta Mechanica sinica 2016年第1期32卷 54-63页

作者： Da-Guo Wang Qing-Xiang Shui School of Environment and Resources Southwest University of Science and Technology

A streamline upwind/Petrov-Galerkin （SUPG） finite element method based on a penalty function is pro- posed for steady incompressible Navier-Stokes equations. The SUPG stabilization technique is employed for the for- mulation of momentum equations. Using the penalty function method, the continuity equation is simplified and the pres- sure of the momentum equations is eliminated. The lid-driven cavity flow problem is solved using the present model. It is shown that steady flow simulations are computable up to Re = 27500, and the present results agree well with previous solutions. Tabulated results for the properties of the primary vortex are also provided for benchmarking purposes.

关键词： Streamline upwind/Petrov-Galerkin (SUPG)finite element method Lid-driven cavity flow Penaltyfunction method High Reynolds number

Scattering of Oblique Water Waves by Two Unequal Surface-Piercing Vertical Thin Plates with Stepped Bottom Topography

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China Ocean Engineering 2018年第5期32卷 524-535页

作者： WANG Li-xian DENG Zheng-zhi WANG Chen WANG Peng Key Laboratory of High Performance Ship technology (Wuhan University of technology) Ministry of Education Departments of Naval Architecture Ocean and Structural EngineeringSchool of TransportationWuhan University of Technology Institute of Port Coastal and Offshore EngineeringOcean CollegeZhejiang University

Based on linear water-wave theory, this study investigated the scattering of oblique incident water waves by two unequal surface-piercing thin vertical rigid plates with stepped bottom topography. By using the matched eigenfunction expansion method and a least square approach, the analytical solutions are sought for the established boundary value problem. The effects of the incidence angle, location of step, depth ratio of deep to shallow waters,and column width between two plates, on the reflection coefficients, the horizontal wave forces acting on the two plates, and the mean surface elevation between the two plates, are numerically examined under a variety of wave conditions. The results show that the existence of the stepped bottom between two plates considerably impacts the hydrodynamic performances of the present system. It is found that the effect of stepped bottom on the reflection coefficient of the present two-plate structure is evident only with waves of the low dimensionless ***, the influence of the step location on the hydrodynamic performance of the present two-plate structure is slight if the step is placed in between the two plates.

关键词： stepped bottom topography two unequal thin vertical rigid plates oblique water waves reflection coefficient wave force

An application of local linear radial basis function neural network for flood prediction

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Journal of Management Analytics 2019年第1期6卷 67-87页

作者： Binaya Kumar Panigrahi Tushar Kumar Nath Manas Ranjan Senapati Department of Civil Engineering Gandhi Institute of Education and TechnologyBaniatangiKhordhaIndia Department of Civil Engineering Indira Gandhi Institute of TechnologySarangaIndia Department of Information technology Veer Surendra Sai University of TechnologyBurlaOdishaIndia

Heavy seasonal rain makes waterway flood and is one of the preeminent reason behind *** causes various perils with outcomes including danger to human life,harm to building,streets,misfortune to horticultural fields and bringing about human ***,prediction of flood is of prime importance so as to reduce exposure of people and destruction of *** paper focuses on applying different neural networks approach,*** Perceptron,Radial Basis functional neural network,Local Linear Radial Basis Functional Neural Network and Artificial Neural Network with Whale Optimization to predict flood in terms of rainfall,gauge,area,velocity,pressure,average temperature,average wind speed that are setup through field and lab investigation from the contextual analysis of river“Daya”and“Bhargavi”.It has always been a troublesome undertaking to predict flood as many factors have influence on it although with this neural network models the prediction accuracy can be optimized using back propagation method which is a widely applied over traditional learning method for neural system because of its preeminent learning *** flood prediction system is built with the four models and a comparison is made which provides us the answer to which model is effective for the prediction.

关键词： multilayer perceptron radial basis functional neural network local linear radial basis functional neural network whale optimization

Mechanisms of hydraulic fracturing in cohesive soil

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Water Science and Engineering 2009年第4期2卷 95-102页

作者： Jun-jie WANG Hui-ping ZHANG Ming-jie ZHAO Xin LIN School of River and Ocean Engineering Chongqing Jiaotong University Chongqing 400074 P. R. China Key Laboratory of Hydraulic and waterway Engineering of Ministry of Education Chongqing Jiaotong University Chongqing 400074 P. R. China

Hydraulic fracturing in the soil core of earth-rockfill dams is a common problem affecting the safety of the dams. Based on fracture tests, a new criterion for hydraulic fracturing in cohesive soil was suggested. Using this criterion, the mechanisms of hydraulic fracturing in cubic soil specimens were investigated. The results indicate that the propagation of the crack in a cubic specimen under water pressure occurs in a mixed mode I-II if the crack face is not perpendicular to any of the principal stresses, and the crack most likely to propagate is the one that is perpendicular to the minor principal stress and propagates in mode I.

关键词： hydraulic fracturing cohesive soil crack propagation mixed mode I-II

Roughness evaluation in shotcrete-lined water tunnels with invert concrete based on cases from Nepal

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 42-59页

作者： Chhatra Bahadur Basnet Krishna Kanta Panthi Department of Geosciences and Petroleum Norwegian University of Science and Technology

Most of the existing roughness estimation methods for water tunnels are related to either unlined or concrete/steel-lined tunnels. With the improvement in shotcrete technology, advancement in tunneling equipment and cost and time effectiveness, future water tunnels built for hydropower projects will consist of rock support with the extensive use of shotcrete lining in combination with systematic bolting and concrete lining in the tunnel invert. However, very little research has been performed to find out tunnel surface roughness for shotcrete-lined tunnels with invert concrete, which is important in calculating overall head loss along the waterway system to achieve an optimum and economic hydropower plant design. Hence, the main aim of this article is to review prevailing methods available to calculate tunnel wall roughness, and to use existing methods of head loss calculation to back-calculate roughness of the shotcrete-lined tunnels with invert concrete by exploiting measured head loss and actual cross-sectional profiles of two headrace tunnels from Nepal. Furthermore, the article aims to establish a link between the Manning coefficient and the physical roughness of the shotcrete-lined tunnel with invert concrete and to establish a link between over-break thickness and physical roughness. Attempts are also made to find a correlation between over-break thickness and rock mass quality described by Q-system and discussions are conducted on the potential cost savings that can be made if concrete lining is replaced by shotcrete lining with invert concrete.

关键词： Shotcrete-lined water tunnels Friction loss Physical and hydraulic roughnesses Tunnel over-break

Modelling Dry Port Systems in the Framework of Inland waterway Container Terminals

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 1019-1046页

作者： Milovan Kovac Snezana Tadic Mladen Krstic Violeta Roso Faculty of Transport and Traffic Engineering University of BelgradeBelgrade11000Serbia Department of technology Management and Economics Chalmers University of TechnologyGothenburg41296Sweden

Overcoming the global sustainability challenges of logistics requires applying solutions that minimize the negative effects of logistics *** most efficient way of doing so is through intermodal transportation(IT).Current IT systems rely mostly on road,rail,and sea transport,not inland waterway *** dry port(DP)terminals has been proven as a sustainable means of promoting and utilizing IT in the hinterland of seaport container *** DP systems consolidate container flows from/to seaports and integrate road and rail transportation modes in the hinterland which improves the sustainability of the whole logistics *** this article,to extend literature on the sustainable development of different categories of IT terminals,especially DPs,and their varying roles,we examine the possibility of developing DP terminals within the framework of inland waterway container terminals(IWCTs).Establishing combined road–rail–inland waterway transport for observed container flows is expected to make the IT systems *** such,this article is the first to address the modelling of such DP *** mathematically formulating the problem of modelling DP systems,which entailed determining the number and location of DP terminals for IWCTs,their capacity,and their allocation of container flows,we solved the problem with a hybrid metaheuristic model based on the Bee Colony Optimisation(BCO)algorithmand themeasurement of alternatives and ranking according to compromise solution(i.e.,MARCOS)multi-criteria decision-making *** results from our case study of the Danube region suggest that planning and developingDP terminals in the framework of IWCTs can indeed be sustainable,as well as contribute to the development of logistics networks,the regionalisation of river ports,and the geographic expansion of their ***,the main contributions of this article are in proposing a novel DP concept variant,mathematically formulating

关键词： Dry port intermodal transport terminal sustainability Bee Colony Optimization MARCOS inland waterway transport

Research on the mechanical properties of the reinforced materials of retaining wall

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International English Education Research 2016年第4期 72-72页

作者： ZHU Yunfei Chongqing jiaotong university National Inland waterway Regulation Engineering technology Research Center Chongqing 400074

The main research purpose of this paper is to study the mechanical properties of the sand gravel packing of the retaining wall under the creep condition of reinforced materials, in order to figure it out, Indoor physi... 详细信息

关键词： mechanical properties retaining wall enforced materials Indoor physical experiments

A Bingham-Plastic Model for Fluid Mud Transport Under Waves and Currents

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China Ocean Engineering 2014年第2期28卷 227-238页

作者：刘春嵘吴博呼和敖德 School of Civil Engineering and Architecture Xiamen University of Technology Institute of Mechanics Chinese Academy of Sciences

simplified equations of fluid mud motion, which is described as Bingham-Plastic model under waves and currents, are presented by order analysis. The simplified equations are non-linear ordinary differential equations which are solved by hybrid numerical-analytical technique. As the computational cost is very low, the effects of wave current parameters and fluid mud properties on the transportation velocity of the fluid mud are studied systematically. It is found that the fluid mud can move toward one direction even if the shear stress acting on the fluid mud bed is much smaller than the fluid mud yield stress under the condition of wave and current coexistence. Experiments of the fluid mud motion under current with fluctuation water surface are carried out. The fluid mud transportation velocity predicted by the presented mathematical model can roughly match that measured in experiments.

关键词： motion of fluid mud fluid mud transport Bingham-Plastic model wave-current interaction