ICE - Institution of Civil Engineers - Virtual Library

Proc. Znsfn Civ. Engrs, Part 2, 1975, 59, June, 265-292 7783 Sediment transport theories : a review The engineer is faced with a multitude of sediment transport theories, each one derived in good faith by a reputable author but often for a limited range of sediment sizes and hydraulic conditions. Computed transport rates vary considerably from theory to theory and choosing which method to adopt in a specific situation is not easy. InarecentinvestigationtheHydraulicsResearchStationhasevaluatedallthe commonly used theories against a large quantity of flume and fielddata. This Paper provides a summary of the work concentrating on eight of the theories...

Proc. Instn Ciu. Engrs, Part 2, 1976, 61, Dec., 803-810 7783 ADDITIONAL DISCUSSION Sediment transport theories: a review W. R. WHITE, H. MILL1 & A. D. CRABBE Dr Chih Ted Yang, U S Army Corps of Engineers, Chicago The Authors made a comprehensivereviewofeightsedimenttransportequations. They concluded that themost reliableequation isthe one proposed by Ackers and White,' which can predict 68% of the data with the discrepancyratio between 0.5 and 2. However, an equation I proposed in 197395is more accurate than any of the equations reviewed by the Authors...

BUTLER ET AL. justification. However, it is possible that the criterion originated by analogy with the threshold velocity, V,, needed to initiate sediment movement. At the threshold of movement, the rate of sediment transport is effectively zero. V , therefore needs to be greater thanV , if sediment is entering at a finite rate into a sewer that is required tobe self-cleansing. The weakness of the criterion is that the value V , relaof tive to V ,appears to be arbitrary and no account is takenof the quantity or type of sediment to be transported orof other factors that may be significant, such as pipe size...

Proc. Instn Civ. Engrs, Part 2, 1916, 61, Mar., 201-221 7783 DISCUSSION Sediment transport theories: a review W.R. WHITE, H. MILL1 & A. D. CRABBE Additional notation coefficient (threshold, Ackers and White') constant (EinsteinlO) constant (Einstein1") drag coefficient (Egiazaroffs4) effective sediment diameter in a mixture particular grain size mean diameter (geometrical) for roughness determination maximum sediment size threshold diameter within a mixture bed load transport efficiency (Bagnold3I) suspended load transport efficiency (Bagnold31) sediment mobility, coarse grain ( A c k e r ~White4) ,~ sediment mobility, fine grain ( A c k e r ~White4) ,~ sediment mobility, general (Ackers? White4) bed transport, dry weight per unit width per unit time suspended transport, dry weight per unit width per unit time total tiansport, dry weight per unit width per unit time coefficient ( A c k e r ~White4) ,~ coefficient (transition, Ackers and White1) particle Reynolds' number with respect to the grain work rate forbed load work rate for suspended load velocity at a level y =0...

Proc. Instn Ciu. Engrs, Part 2, 1971, 63,June, 41 1-425 7993 Sediment balance method for irrigation canal design K. v. H. SMITH, MSc, PhD,MICE, MIStructE, MASCE, FlPHE* An alternative to the regime method of canal design is presented, which is explicit in that the designs are related to bed material size and the required sediment transport capability. Designed canal sections and slopes are compared with those derivedby the regime method. The alternative method is applicable to bed material sizes of approximately 0...

7241 Computation of sediment transport in irrigation canals H. M. CHAUDHRY, MSc(Eng)' K. V. H. SMITH, MSC, MlCEt H. VIGIL, MSc(Eng)' The regime method has been an effective means for the design of unlined irrigation canals and canal systems. However, when the basic conditions of the design problem differ appreciably from those for which the regime method was derived, other approaches are necessary. One of the most important requirements at the present time is areliablemethod for computingsediment transport incanals at various stages of flow...

Experiments on the transport of graded sediment B. B. Willetts, MA, PhD, CEng, FICE, FRSE, G. Pender, BSc, PhD, CEng, MICE and I. K. McEwan, BSc(Eng), PhD, CEng, MICE & Proc. Instn Civ. Engrs Wat., Marit. & Energy, 1998, 130, Dec., 217225 Paper 11679 Written discussion closes 15 April 1999 Four large-scale experiments are reported on the transport of graded sediments in a straight channel in the domain of partial sediment mobility (in which not all size fractions are fully mobile)...

Proc. Instn Ciu. Engrs, Part 1, 1977, 62, May, 343-346 HYDROLOGICAL GROUP INFORMAL DISCUSSION Developments in sediment transport theories introduced by J. R. D. Francis, BSc(Eng). FICE, and P. Ackers, MSc(Eng), FICE reported by A. Scott-Moncrieff ProfessorsFrancis and Ackers provokedseveralworthwhilecommentaries on work being done ondiffering aspects of the subject. The evident lack of common ground for a real discussion may reflect the poor state of knowledge of the underlying mechanics and the variety and isolation of possible approaches to understanding one or other aspect of the subject...

Proc. Instn Ciu. Engrs, Part 2,1981,71, Sept., 879-892 8484 Mathematical simulation of sediment movement in streams R. BETTESS, BSc, PhD* W. R. WHITE, BSc, PhD, MICE* This Paper is concerned with the modelling of sediment movement in streams and makes particular reference to the changes in bed levels and the changes in the composition of the bed materials which occur over periods of several years. The principles on which the model is based are described and comparison made between the performance of the model with field and flume data...

BUTLER ET AL. demonstrate an apparent cohesive strength when subjected to shear. Combined sewers contain a mixture of the sediments occurring separately in foul and surface water sewers; the inorganic particles tend to become coated with slimes and greases which, together with the organic particles in the bed, leads to some cohesion. 8. The types of sediment in combined sewers can be classified in terms important of properties such as size grading, density and moisture content, proportions of organic and inorganic materials and polluting potential. A single quantitative classification system is difficult because of the large amountof independent variation in each of the many properties and because of the tendency of the properties to change throughout the system and with time...