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2015 | Buch

Advances in Water Resources Engineering

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This book, Advances in Water Resources Engineering, Volume 14, covers the topics on watershed sediment dynamics and modeling, integrated simulation of interactive surface water and groundwater systems, river channel stabilization with submerged vanes, non-equilibrium sediment transport, reservoir sedimentation, and fluvial processes, minimum energy dissipation rate theory and applications, hydraulic modeling development and application, geophysical methods for assessment of earthen dams, soil erosion on upland areas by rainfall and overland flow, geofluvial modeling methodologies and applications, and environmental water engineering glossary.

Inhaltsverzeichnis

Frontmatter
1. Watershed Sediment Dynamics and Modeling: A Watershed Modeling System for Yellow River
Abstract
Soil erosion is the root cause of environmental and ecological degradation in the Loess Plateau of the Yellow River. Watershed sediment dynamics was fully analyzed here, and a physically based, distributed, and continuous erosion model at the watershed scale, named the Digital Yellow River Integrated Model (DYRIM), was developed. The framework, the key supporting techniques, and the formulation for natural processes were described. The physical processes of sediment yield and transport in the Loess Plateau are divided into three subprocesses, including the water yield and soil erosion on hillslopes, gravitational erosion in gullies, and hyperconcentrated flow routing in channels. For each subprocess, a physically based simulation model was developed and embedded into the whole model system. The model system was applied to simulate the sediment yield and transport in several typical years in different watersheds of the Yellow River, and the simulation results indicated that this model system is capable of simulating the physical processes of sediment yield and transport in a large-scale watershed.
Guangqian Wang, Xudong Fu, Haiyun Shi, Tiejian Li
2. Integrated Simulation of Interactive Surface-Water and Groundwater Systems
Abstract
Effective management of watersheds and ecosystems requires a comprehensive knowledge of hydrologic processes, and the ability to predict and quantify reliably the impacts due to anthropogenic or natural changes in water availability and water quality. For integrated water resources management studies in which both surface water and groundwater are interactive, a technically rigorous and physically based approach is essential. Simulation models have been used increasingly to provide a predictive capability in support of water resources, and environmental and restoration projects. Often, simplified models are used to quantify complex hydrologic and transport processes in surface and subsurface domains. Such models incorporate restrictive assumptions relating to spatial variability, dimensionality, and interactions of components in flow and transport processes. During the past decade, with the advent of high-speed personal computers, a number of rigorous integrated surface-water/groundwater models have been developed to circumvent these limitations. In general, a typical model of an integrated hydrologic system may be divided into three interactive and interconnected domains: subsurface, overland, and channels/streams, in which water flow and transport of constituents can occur. In this chapter, the following are presented and discussed: a description of relevant processes relating to water flow and solute transport in conjunction with governing equations for all domains; procedures for model development and calibration; and two field application examples.
Varut Guvanasen, Peter S. Huyakorn
3. River Channel Stabilization with Submerged Vanes
Abstract
Submerged vanes are an unobtrusive and cost-effective way for river engineers to address many problems associated with river channel stability and river management in general. The vanes are small flow-training structures designed and installed on the riverbed to modify the near-bed flow pattern and redistribute flow and sediment transport within the channel cross section. The structures are laid out so they create and maintain a flow and bed topography that is consistent with that of a stable channel creating optimum conditions for managing the river. A relatively new technology, submerged vanes are a low-impact method for restoring riverbanks, stabilizing or re-meandering river reaches previously modified (straightened) by humans, increasing flood flow capacity, reducing sediment deposits, and for helping maintain or enhance the ecosystem in and around rivers. Following laboratory research and feedback from field installations, guidelines are now available for designs that are effective and sustainable. These guidelines are described in the book by Odgaard River Training and Sediment Management by Submerged Vanes, ASCE Press, 2009. Following a brief summary of the theory with illustrations from the ASCE book (reprinted with permission of ASCE), this chapter presents the latest feedback from field installations and suggestions for future applications.
A. Jacob Odgaard
4. Mathematic Modelling of Non-Equilibrium Suspended Load Transport, Reservoir Sedimentation, and Fluvial Processes
Abstract
This chapter consists of two parts: mechanism of non-equilibrium transport of non-uniform suspended load and its application to mathematical modelling. Based on a stochastic approach of sediment transport proposed by the authors, a 1D equation of non-equilibrium transport for each size group of non-uniform sediment is developed. The equations to predict the change of sediment concentration and the corresponding size distribution of suspended load and bed material are also derived. The concept that changes in size distribution are interrelated to sediment-carrying capacity is explored. These results reveal the essence of sediment transport of non-uniform sediment. In the second part, a mathematical model incorporating the mentioned equations to compute deposition and scouring in reservoirs as well as the fluvial processes of river channels has been developed. Verification of the model agrees well with field data.
Qiwei Han, Mingmin He
5. Minimum Energy Dissipation Rate Theory and Its Applications for Water Resources Engineering
Abstract
Minimum energy dissipation rate principle can be derived from minimum entropy production principle. Minimum entropy production principle is equivalent to the minimum energy dissipation rate principle. The concept of minimum energy dissipation rate principle is that, when an open system is at a steady nonequilibrium state, the energy dissipation rate is at its minimum value. The minimum value depends on the constraints applied to the system. If the system deviates from the steady nonequilibrium state, it will adjust itself to reach a steady nonequilibrium state. The energy dissipation rate will reach a minimum value again. In order to verify the fluid motion following minimum energy dissipation rate principle, re-normalisation group (RNG) k -ε turbulence model and general moving object (GMO) model of Flow-3D were applied to simulate fluid motion in a straight rectangular flume. The results show that fluid motion satisfies the minimum energy dissipation rate principle. Variations of energy dissipation rate of alluvial rivers have been verified with field data. When a river system is at a relative equilibrium state, the value of its energy dissipation rate is at minimum. The minimum value depends on the constraints applied to the river system. However, due to the dynamic nature of a river, the minimum value may vary around its average value. When a river system evolves from a relative state of equilibrium to another state, the process is very complicated. The energy dissipation rate does not necessarily decrease monotonically with respect to time. When a system is at a new relative state of equilibrium, the energy dissipation rate must be at a minimum value compatible with the constraints applied to the system. Hydraulic geometry relationships can be derived from the minimum energy dissipation rate principle. Combining the minimum energy dissipation rate principle with optimization technology as the objective function under the given constraints, the optimum design mathematical models can be developed for a diversion headwork bend structure and stable channel design.
Guobin Xu, Chih Ted Yang, Lina Zhao
6. Hydraulic Modeling Development and Application in Water Resources Engineering
Abstract
The use of modeling has become widespread in water resources engineering and science to study rivers, lakes, estuaries, and coastal regions. For example, computer models are commonly used to forecast anthropogenic effects on the environment, and to help provide advanced mitigation measures against catastrophic events such as natural and dam-break floods. Linking hydraulic models to vegetation and habitat models has expanded their use in multidisciplinary applications to the riparian corridor. Implementation of these models in software packages on personal desktop computers has made them accessible to the general engineering community, and their use has been popularized by the need of minimal training due to intuitive graphical user interface front ends. Models are, however, complex and nontrivial, to the extent that even common terminology is sometimes ambiguous and often applied incorrectly. In fact, many efforts are currently under way in order to standardize terminology and offer guidelines for good practice, but none has yet reached unanimous acceptance. This chapter provides a view of the elements involved in modeling surface flows for the application in environmental water resources engineering. It presents the concepts and steps necessary for rational model development and use by starting with the exploration of the ideas involved in defining a model. Tangible form of those ideas is provided by the development of a mathematical and corresponding numerical hydraulic model, which is given with a substantial amount of detail. The issues of model deployment in a practical and productive work environment are also addressed. The chapter ends by presenting a few model applications highlighting the need for good quality control in model validation.
Francisco J.M. Simões
7. Geophysical Methods for the Assessment of Earthen Dams
Abstract
Dams and levees are an integral part of the fluvial system in watersheds. The structural integrity of this infrastructure is of concern to the nation and to those directly impacted should failure occur. There are some 88,000 dams and 110,000 miles of levees in the USA. Many of those are earthen embankments and structures subject to failure by seepage and overtopping especially under extreme conditions of rainfall, runoff from contributing source areas, and snowmelt. They require routine inspection and the availability of technologies to assess their stability and safety conditions. This chapter discusses in a comprehensive manner the various geophysical and geotechnical techniques, and related technologies that are capable of rapidly assessing the integrity and stability of dams and levees. This chapter also discusses the underlying principles of these techniques. Finally, it presents case studies in which these techniques were used.
Craig J. Hickey, Mathias J. M. Römkens, Robert R. Wells, Leti Wodajo
8. Soil Erosion on Upland Areas by Rainfall and Overland Flow
Abstract
Soil erosion in agricultural watersheds is a systemic problem that has plagued mankind ever since the practice of agriculture began some 9000 years ago. It is a worldwide problem, the severity of which varies from location to location depending on weather, soil type, topography, cropping practices, and control methods. Research to address and predict soil loss from agricultural land and in watersheds began in earnest in the 1930s following the events of the Dust Bowl. Early research primarily consisted of monitoring of soil loss from natural runoff plots and small watersheds. Gradually and over time, the focus shifted toward the development of prediction equations based on the acquired soil loss database. With computer technology, modeling watershed erosion and sedimentation processes became routine. Also, fundamental research was conducted to acquire a better understanding of the complex aspects of soil erosion and sediment transport processes and to fill in knowledge gaps in cases where data were not readily available. In recent years, most soil loss from upland areas occurs as gully erosion. This chapter presents a background of the knowledge that was systematically acquired in predicting soil erosion from upland areas and the technology that was developed and is used today. This chapter does not address all the aspects of upland soil erosion, but focuses primarily on the erodibility (K-factor) and hydrological aspects (R-factor) of the most widely used erosion prediction equations: the revised universal soil loss equation, version 2 (RUSLE2) and water erosion prediction project model (WEPP) models-based formulae. This chapter also includes a presentation of the Chinese approach of adapting gully erosion predictions according to the universal soil loss equation (USLE) format. Finally, ongoing research and technology development using light detection and ranging (LiDAR) and photogrammetry in gully erosion predictions is discussed.
Mathias J. M. Römkens, Robert R. Wells, Bin Wang, Fenli Zheng, Craig J. Hickey
9. Advances in Geofluvial Modeling: Methodologies and Applications
Abstract
Stream bank erosion is an important form of channel change in alluvial environments; it should be accounted for in geomorphic studies, river restoration, dam removal, and channel maintenance projects. Recently, one-dimensional (1D) and two-dimensional (2D) flow and mobile-bed numerical models are becoming useful engineering tools for predicting channel morphological responses to stream modifications. Most, however, either ignore bank erosion or implement only simple ad hoc methods. A combined modeling of vertical and lateral fluvial processes in streams, i.e., geofluvial modeling, is important yet still at its research stage. In this chapter, advances in geofluvial modeling are presented. First, a literature review is provided in the area of geofluvial modeling. Second, important geofluvial processes are discussed as they need to be incorporated into models. Third, a recently developed 2D geofluvial model, SRH-2D, is described. SRH-2D incorporates processed-based bank erosion modules into a 2D mobile-bed module; it is developed with the primary objective of advancing the geofluvial modeling toward a practical engineering tool. Bank erosion modeling consists of a uniform retreat module and mechanistic failure module; both are suitable for uniform and multilayer banks with noncohesive or cohesive materials. The coupling techniques are developed that emphasize ease of use and model robustness (stability). Fourth and final, a number of laboratory and field cases are selected to validate and verify the geofluvial model; application cases are also presented to demonstrate the practical aspects of the model. It is found that the state-of-the-art 2D geofluvial modeling is becoming practical to assist project planning, design, and evaluation. SRH-2D can predict accurately for some streams, but only qualitatively for more complex streams.
Yong G. Lai
10. Environmental Water Engineering Glossary
Abstract
Technical and legal terms commonly used by environmental water engineers are introduced. This chapter covers mainly the glossary terms used in the following two books:
1.
Advances in Water Resources Engineering and
 
2.
Modern Water Resources Engineering,
 
The above Two books form a miniseries in the field of water resources engineering.
Mu-Hao Sung Wang, Lawrence K. Wang
Metadaten
Titel
Advances in Water Resources Engineering
herausgegeben von
Chih Ted Yang
Lawrence K. Wang
Copyright-Jahr
2015
Electronic ISBN
978-3-319-11023-3
Print ISBN
978-3-319-11022-6
DOI
https://doi.org/10.1007/978-3-319-11023-3