A new, very simple and dependable field sediment sampler has been developed. It is a multi-siphon device that samples suspended sand from seven elevations simultaneously. The 65 concentration profiles that have been obtained so far are presented, complete with hydrodynamics and bed sediment data. The profiles were measured under breaking and non-breaking waves in a wide rage of coastal environments all over Australia. These data together with a review of oscillatory boundary layer flow and the motion of suspended sand in an accelerated non-uniform flow lead to a range of new insights into the processes of sediment entrainment under waves. (Author).
This book focuses on the phenomenon of sediment erosion and resuspension in the Yellow River delta, China, which is a vital issue involved in understanding the sediment transport processes in estuarine and coastal environments, and how these contribute to the nature and distribution of geohazards in the subaqueous Yellow River delta and Bohai Sea. The most important sections of this book will be the detailed physical mechanisms and theoretical models of sediment erosion and resuspension problem fully considering the wave-induced seabed dynamic response to waves, which are particularly useful for postgraduate students and junior researchers entering the discipline of estuary and coastal sedimentation, marine geotechnical engineering, estuary and coastal engineering, harbor and waterway engineering and coastal environmental protection. This book can also serve as a textbook for advanced graduate students of Marine Engineering Geology and Estuarine Sediment Dynamics.
This book treats the subject of sediment transport in the marine environment, covering transport of non-cohesive sediment by waves and current in- and outside the surf zone. It can be read independently, but a background in hydraulics and basic wave mechanics is required. It is intended for M.Sc. and Ph.D. students. The primary aim of the book is to describe the physical processes of sediment transport and how to represent them in mathematical models. It does not present a large number of different formulae for the sediment transport rates under various conditions. The book can be divided in two main parts; in the first, the relevant hydrodynamic theory is described; in the second, sediment transport and morphological development are treated. The hydrodynamic part contains a review of elementary theory for water waves, chapters on the turbulent wave boundary layer and the turbulent interaction between waves and currents, and finally, surf zone hydrodynamics and wave driven currents. The part on sediment transport introduces the basic concepts (critical bed shear stress, bed load, suspended load and sheet layer, near-bed concentration, effect of sloping bed); it treats suspended sediment in waves and current and in the surf zone, and current and wave-generated bed forms. Finally, the modelling of cross-shore and long-shore sediment transport is described together with the development, of coastal profiles and coastlines.
The MIT mission - "to bring together Industry and Academia and to nurture the next generation in computational mechanics is of great importance to reach the new level of mathematical modeling and numerical solution and to provide an exciting research environment for the next generation in computational mechanics." Mathematical modeling and numerical solution is today firmly established in science and engineering. Research conducted in almost all branches of scientific investigations and the design of systems in practically all disciplines of engineering can not be pursued effectively without, frequently, intensive analysis based on numerical computations.The world we live in has been classified by the human mind, for descriptive and analysis purposes, to consist of fluids and solids, continua and molecules; and the analyses of fluids and solids at the continuum and molecular scales have traditionally been pursued separately. Fundamentally, however, there are only molecules and particles for any material that interact on the microscopic and macroscopic scales. Therefore, to unify the analysis of physical systems and to reach a deeper understanding of the behavior of nature in scientific investigations, and of the behavior of designs in engineering endeavors, a new level of analysis is necessary. This new level of mathematical modeling and numerical solution does not merely involve the analysis of a single medium but must encompass the solution of multi-physics problems involving fluids, solids, and their interactions, involving multi-scale phenomena from the molecular to the macroscopic scales, and must include uncertainties in the given data and the solution results. Nature does not distinguish between fluids and solids and does not ever repeat itself exactly.This new level of analysis must also include, in engineering, the effective optimization of systems, and the modeling and analysis of complete life spans of engineering products, from design to fabrication, to possibly multiple repairs, to end of service.
This comprehensive and up-to-date volume contains 367 papers presented at the 29th International Conference on Coastal Engineering, held in Lisbon, Portugal, 19-24 September 2004. It is divided into five parts: waves; long waves, nearshore currents, and swash; sediment transport and morphology; coastal management, beach nourishment, and dredging; coastal structures. The contributions cover a broad range of topics including theory, numerical and physical modeling, field measurements, case studies, design, and management. Coastal Engineering 2004 provides engineers, scientists, and planners state-of-the-art information on coastal engineering and coastal processes.The proceedings have been selected for coverage in:
This Proceedings contains over 260 papers on cutting-edge research presented at the eighth international Symposium on Coastal Sediment Processes, held May 11 - 15, 2015, in San Diego, California, USA. This technical specialty conference was devoted to promoting an interdisciplinary exchange of state-of-the-art knowledge among researchers in the fields of coastal engineering, geology, oceanography, and related disciplines, with the theme of Understanding and Working with Nature.Focusing on the physical aspects of the sediment processes in various coastal environments, this Proceedings provides findings from the latest research and newest engineering applications. Sessions covered a wide range of topics including barrier islands, beaches, climate and sea level, cohesive and noncohesive sediments, coastal bluffs, coastal marsh, dredged sediments, inlet and navigation channels, regional sediment management, river deltas, shore protection, tsunamis, and vegetation-sediment interaction. Several special sessions included: Relevant science for changing coastlines: A Tribute to Gary Griggs; North Atlantic Coast Comprehensive Study and post-super-storm Sandy work; long-term coastal evolution; barrier islands of Louisiana; sea-level rise and super storms in a warming world; predicting decadal coastal geomorphic evolution; and contrasting Pacific coastal behavior with El Niño Southern Oscillation (ENSO), are also featured.
The Coastal Inlets Research Program (CIRP) is developing predictive numerical models for simulating the waves, currents, sediment transport, and morphology change at and around coastal inlets. Water motion at a coastal inlet is a combination of quasi-steady currents such as river flow, tidal current, wind-generated current, and seiching, and of oscillatory flows generated by surface waves. Waves can also create quasi-steady currents, and the waves can be breaking or non-breaking, greatly changing potential for sediment transport. These flows act in arbitrary combinations with different magnitudes and directions to mobilize and transport sediment. Reliable prediction of morphology change requires accurate predictive formulas for sediment transport rates that smoothly match in the various regimes of water motion. This report describes results of a research effort conducted to develop unified sediment transport rate predictive formulas for application in the coastal inlet environment. The formulas were calibrated with a wide range of available measurements compiled from the laboratory and field and then implemented in the CIRP's Coastal Modeling System. Emphasis of the study was on reliable predictions over a wide range of input conditions. All relevant physical processes were incorporated to obtain greatest generality, including: (1) bed load and suspended load, (2) waves and currents, (3) breaking and non-breaking waves, (4) bottom slope, (5) initiation of motion, (6) asymmetric wave velocity, and (7) arbitrary angle between waves and current. A large database on sediment transport measurements made in the laboratory and the field was compiled to test different aspects of the formulation over the widest possible range of conditions. Other phenomena or mechanisms may also be of importance, such as the phase lag between water and sediment motion or the influence of bed forms. Modifications to the general formulation are derived to take these phenomena into account. The.
