Cohesive Sediments In Open Channels

Control the impact of cohesive sediments on open channels by managing the effects of silt, clay and other sediments in harbors, estuaries and reservoirs. Cohesive Sediments in Open Channels provides you with a practical framework for understanding how cohesive sediments are transported, deposited and eroded. One of the first books to approach the subject from an engineering’s perspective, this book supplies insight into applying hydraulic design as well as understanding the behavior of cohesive sediments in a flow field. Properties and of the nature and the origin of the interparticle physicochemical forces The forces between clay particles and the process of flocculation Processes and dynamics of flocculation and the hydrodynamic behavior of cohesive sediments Transport processes of sediments by flowing water and related equations are first presented and explained Deposition and resuspension of beds deposited from suspension from flowing waters Engineering applications of the hydraulics of cohesive sediments

There is an alarming tendency today to assume that something calculated by a computer must be correct, yet the phrase 'garbage in, garbage out' (gigo) is possibly nowhere more (generally) appropriate than in computer modelling of cohesive sediment behaviour. The behaviour of 'mud' is highly complex and one only needs to look at a sample under a microscope to see why - the variety of particle shapes, not to mention the presence of living organisms, make it a substance with properties virtually unique to its situation which even change with time. For many years most researchers tended to avoid it, preferring to study sand and gravel, but a dedicated few tackled it and found a forum for discussing their work in the first Cohesive Sediments Workshop in Florida in 1980. The workshop met about every three years resulting in publication of some of the most definitive papers on the subject. By 1994 it was time to recognise the extensive research being carried on in Europe by holding the workshop in that region. Intercoh '94 (the 4th Nearshore and Estuarine Cohesive Sediment Transport Conference) drew together about 100 of the world's leading researchers in the field. The resulting papers, presented in this volume, truly represent the definitive state of the art on the measurement and modelling of mud properties today.

Fine Sediment in Open Water is mainly written for professional engineers working in estuaries and coastal systems. It provides the basis for a fundamental understanding of the physical, biological and chemical processes governing the transport and fate of fine sediment in open water and explains how this understanding can steer engineering studies with numerical models. This is a unique treatment of processes at a variety of spatial and temporal scales, from the micro-scale (colloid scale) to system-wide scales, and from intra-tidal time periods to decades.Beginning with the processes governing the transport and fate of fine sediment in shallow open water, the first eight chapters are dedicated to the hydrodynamic, soil mechanics and biological processes which determine fine sediment concentrations in the water column, in/on the bed and the exchange of sediment between bed and water column. The next two chapters treat the net fluxes of fine sediment as a function of asymmetries in forcing and sediment properties. These fundamental processes form the basis for the subsequent chapters on modeling in which the governing equations are presented, and tools are provided to aggregate and parameterize the various processes elaborated in the first eight chapters. Further, any numerical model study should be based on a conceptual model, as illustrated in the final five chapters, which provide examples of numerical modeling studies on the transport and fate of fine sediment in a coastal sea, an estuary, a tidal river, a lake, and around and within a harbor basin.Related Link(s)

In Physical Processes in Estuaries the present day knowledge of the physics of transport phenomena in estuaries and their mathematical treatment is summarized: It is divided into following parts: - Water movements in estuaries - Estuarine fronts and river plumes - Internal waves and interface stability - Fine sediment transport, aggregation of particles, settling velocity of mud flocs - Sedimentation and erosion of fine sediments. For each topic an up-to-date review and recommendations for future research are given, followed by results of original studies. Since estuarine environments are the first to be threatened by urbanization and industrial exploitation this book is an important tool for students and researchers of environmental problems as well as for consultants and water authorities.

This book presents observations on the phenomena of fine sediment transport and their explanations under process-related divisions such as flocculation, erosion, and deposition. The text is a compilation of the author's lecture notes from nearly four decades of teaching and guiding graduate students in civil and coastal engineering. Illustrations of fine sediment transport processes and their complexities given in the book are taken from field and laboratory-based observations by the author and his students, as well as numerous investigators. The wide-ranging composition of particles (of inorganic and organic matter), their universal presence and their complex interactions with hydraulic forces make this branch of science a difficult one to deal with in a single treatise. It is therefore essential to study fine sediment transport as an independent subject rather than cover it in no more than a single chapter as many texts on coarse sediment transport have done. Even though the entire coverage is “introductory”, the twelve chapters collectively include more material than what can be reasonably dealt with in a one semester, three-credit course. The book includes an extensive description of the components of fine-grained — especially cohesive — sediment transport. It covers the development of the subject in scientific and engineering applications mainly from the 1950s to its present state. Solved examples and chapter-end exercises are also included. This text is aimed at senior civil engineering undergraduates and graduate students who, in the normal course of their study, seldom come across the subject of fine sediment transport in their curricula. Interested students should have a basic understanding of the mechanics of fluid flow and open channel hydraulics.

This book discusses cohesive sediments. It is based on presentations at the Nearshore and Estuarine Cohesive Sediment Transport Workshop held in 1991.

This book expounds the hydraulics of fine sediment which is almost ubiquitously found in coastal and estuarine waters, and in rivers, lakes, and reservoirs. Although the basic subject may be categorized as applied marine physics in shallow waters, several physicochemical and biological effects on particulate transport have been addressed.In this second edition most of the chapters have been substantially updated, rewritten, and expanded. Overall, a significant change has also been made throughout by replacing sediment concentration, a unit dependent quantity at the heart of numerous descriptions, measurements, and calculations, with the nondimensional sediment volume fraction. It marks a divergence in the manner in which fine sediment transport data and calculations are conventionally presented.The book is mainly written for civil engineering seniors and graduate students, to offer a comprehensive foundation in hydraulics of fine sediment. The book is also a useful reference for researchers interested in the effects of physical chemistry and biology on fine sediment transport in water and to an extent on coastal and estuarine morphodynamics, sediment transport, port and harbor engineering, and applied shallow watwer marine physics. The book is also recommended reading for those interested in understanding particle transport in water.Related Link(s)