Sediment Transport

SEDIMENT

TRANSPORT

Zhou Liu

3. udgave.

januar 2001

Laboratoriet for Hydraulik og Havnebygning Instituttet for Vand, Jord og Miljøteknik Aalborg Universitet

Preface
Flow and sediment transport are important in relation to several engineering topics, e.g. erosion around structures, backfilling of dredged channels and nearshore morphological change. The purpose of the present book is to describe both the basic hydrodynamics and the basic sediment transport mechanism. The reader’s background should be a basic course in wave theory and fluid mechanics. Chapter 1 deals with fundamentals in fluid mechanics with emphasis on bed shear stress by currents, while Chapter 3 discusses wave boundary layer theory. They are both written with a view to sediment transport. Sediment transport in rivers, cross-shore and longshore are dealt with in Chapters 2, 4 and 5, respectively. It is not the intention of the book to give a broad review of the literature on this very wide topic. The book tries to pick up information which is of engineering importance. An obstacle to the study of sedimentation is the scale effect in model tests. Whenever small-scale tests, large-scale tests and field investigations are available, it is always the result from field investigations which is referred to.

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CONTENTS

Contents
1 Steady uniform flow in open channels 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Types of flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Prandtl’s mixing length theory . . . . . . . . . . . . . . . . . . . . . . . . . Fluid shear stress and friction velocity . . . . . . . . . . . . . . . . . . . . Classification of flow layer . . . . . . . . . . . . . . . . . . . . . . . . . . . Velocity distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 4 5 7 9

Ch´zy coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 e Drag coefficient, lift coefficient and friction coefficient . . . . . . . . . . . . 14 Exercise .

References: Bijker, E.W. , 1971. Longshore transport computation. Journal of Waterways, Harbours and Coastal Engineering Division, ASCE, Volume 97, WW 4, pp687-701. Burcharth, H.F. , 1984. Kystsikrinspricipper DIEU-Seminar om Kystsikring, Laboratoriet for Hydraulik og Havnebygning, Aalborg Universitet, 1984 CERC , 1984. Shore Protection Manual. Coastal Engineering Research Center, Waterways Experiment Station, U.S. Army Corps of Engineers, 1984. Jrgen Fredse and Rolf Deigaard. , 1992. Mechanics of Coastal sediment transport. Advanced Series on Ocean Engineering, Volume 3, Series Editor-in-Chief Philip L-F Liu, World Scientific Publishing Co. Pte.Ltd. Hallermeier, R.J. , 1983. Sand transport limits in coastal structure designs. Proceedings of Coastal Structure’83, pp 703-716, ASCE, 1983. Kamphuis, J.W. , 1990. Littoral transport rate. Proceedings of the 22nd International Conference on Coastal Engineering, ASCE, pp2402-2415. Komar, Paul D. , 1996. Coastal Geology: Processes and pohpology of coasts and beaches. Short Course attached to 25th International Conference on Coastal Engineering, Orlando, USA, 1996 Kraus, N.C. , 1992. Engineering approaches to cross-shore sediment transport processes. Proceedings of the Short Course on Design and Reliability of Coastal Structures, attached to 23rd International Conference on Coastal Engineering, Venice, Italy, 1992 Madsen, O.S. , 1993. Sediment transport on the shelf. Short Course attached to 25th International Conference on Coastal Engineering, Orlando, USA, 1996 Nielsen Peter. , 1992. Coastal bottom boundary layers and sediment transport. Advanced Series on Ocean Engineering, Volume 4, Series Editor-in-Chief Philip L-F Liu, World Scientific Publishing Co. Pte.Ltd. Raudkivi, A.J. , 1976. Loose boundary hydraulics. 2nd Edition, Pergamon Press, 1976. Van Rijn, L.C. , 1990. Principles of fluid flow and surface waves in rivers, estuaries, seas and oceans. Aqua Publications, The Netherlands, 1990 71