The background for the Workshop on Cohesive Sediment Dynamics - . !!!!!. Special Reference to Physical Processes in Estuaries is briefly outlined in Chapter I. Here I wish to acknowledge those whose support I consider to be pivotal to this under taking. My deepest appreciation goes to Cynthia Vey, whose organizational skills and dedicated effort made the completion of this volume possible. Thanks are also due to Gail Terry for workshop organization, Jean Branson for word processing and Lillean Pieter for helping with drawings. Finally, I must express my sincere appreciation to Arthur Ezra 9f the National Science Foundation for providing support (through Grant No. CEE-8401185) for the workshop, and to Hsiang Wang for depart mental encouragement. With deepest regret, I must note the untimely death of Ranjan Ariathurai, 39, on June 5, 1985, before this volume could be published. He was a guiding force to many within the small group of researchers in cohesive sediment dynamics, and his professional brilliance and inspirational personal qualities constituted the true spirit . behind the workshop. I trust this volume will serve, albeit in a small way, as a fitting memory to this spirit, and to the remarkable professional contributions Ranjan made during his short career. Professor Ray B. Krone Professor Emmanuel Partheniades Department of Civil Engineering Department of Engineering Sciences University of California University of Florida Davis, California Gainesville, Florida TABLE OF CONTENTS CHAPTER PAGE I. INTRODUCTION Ashish J. Mehta •••••••••••••••••••••••••••••••••••••••••••••••••••• 1 II.

This volume is the product of the International Conference on Cohesive Sediment Transport (INTERCOH 2003) held at the Virginia Institute of Marine Science, U.S.A., during October 1-4, 2003. The topics included in this monograph range from basic research on cohesive sediment dynamics to practical applications. Also included with this book is a database that contains all experimental results as well as a comparison of numerical simulation results supported by the COSINUS project.* Provides fundamental knowledge of the dynamics of cohesive sediments* Presents practical applications of new finds on sedimentary processes* Includes valuable ready-for-use data

The ability to predict the movement of cohesive sediment within coastal, estuarine or inland waters has a significant economic and ecological importance in the development of new engineering works and the maintenance of existing installations. Dynamics of estuarine muds clearly describes the most up-to-date developments in this field and contains information about improved procedures and how they can be applied to a variety of engineering projects. Drawing on a wide range of new data and new concepts in mud research, this concise volume presents the main processes of cohesive sediment behaviour, namely, erosion, transport, deposition and consolidation. It includes subsections on Knowledge, intended to show the practising engineer which parameters are important in each of the processes and Procedure, which will enable broad estimates of erosion, transport, deposition and consolidation to be made based on knowledge of the site conditions. Dynamics of estuarine muds is essential reading for the practising engineer who is involved in coastal, estuarine or inland water construction. A companion volume to Dynamics of marine sands, this excellent book provides invaluable information about this complex topic in a readily accessible manner.

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.

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 is an introduction to the physical processes of cohesive sediment in the marine environment. It focuses on highly dynamic systems, such as estuaries and coastal seas. Processes on the continental shelf are also discussed and attention is given to the effects of chemistry, biology and gas.The process descriptions are based on hydrodynamic and soil mechanic principles, which integrate at the soil-water interface. This approach is substantiated through a classification scheme of sediment occurrences in which distinction is made between cohesive and granular material. Emphasis is also placed on the important interactions between turbulent flow and cohesive sediment suspensions, and on the impact of flow-induced forces on the stability of the seabed. An overview of literature on cohesive sediment dynamics is presented and a number of new developments are highlighted, in particular in relation to floc formation, settling and sedimentation, consolidation, bed failure and liquefaction and erosion of the bed. Moreover, it presents a summary on methods and techniques to measure the various sediment properties necessary to quantify the various parameters in the physical-mathematical model descriptions. A number of examples and case studies have been included.