Computer Simulation of Shear Flows of Granular Material

Campbell, Charles S.; Brennen, Christopher E.

doi:10.1016/b978-0-444-42192-0.50032-3

Cited by 43 publications

(31 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Initial models, based on disc-shaped particles, have evolved and have led to numerous studies dealing with the micromechanics of soils [3] and other large-scale problems such as flow and impact analysis involving granular media [4][5][6][7][8][9]. This tool has explained the mechanisms of stress transfer through grain contacts and has helped also to disclose the nature of some basic stress-strain features such as the generation of shear bands [10] or the underlying phenomena behind liquefaction [11].…”

Section: Introductionmentioning

confidence: 99%

Microstructural deformation mechanisms of unsaturated granular soils

Gili

Alonso

2002

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

SUMMARYA discrete model for unsaturated granular soils has been developed. Three discrete entities have been defined: particles, water menisci and pores. Local interaction forces and water transfer mechanisms have been integrated into a model through the appropriate equilibrium and balance equations. The results of several numerical tests using this model have been described and discussed. Simulations include wetting and drying under load tests, the application of suction cycles and the effect of a deviatoric stress ratio on wetting-induced collapse. The model reacts just as true granular soil samples behave in laboratory tests. The model provides a new insight into the internal mechanisms leading to large-scale features of behaviour such as wetting-induced collapse or the increase in soil strength provided by suction. The paper also stresses that matric suction changes acting on a granular structure are capable of explaining most of the macroscopic features of stress-strain behaviour.

show abstract

Section: Introductionmentioning

confidence: 99%

Microstructural deformation mechanisms of unsaturated granular soils

Gili

Alonso

2002

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

show abstract

“…(7) As the overburden increases, the rate of basal shearing decreases and v increases there; this implies dynamic friction decreases with increasing overburden (Dent, 1986). If the overburden is kept constant but flow height is varied, no change in conditions at the basal boundary is predicted for simple shear flows (Campbell and Brennen, 1983). (8) For chute flows with slip at the boundary, higher slope angles imply v is lower near the boundary than in the interior of the flow.…”

Section: Summary and Discussionmentioning

confidence: 99%

“…(3) For simple shear, dynamic friction (p) increases as v decreases (in contrast to static friction); v decreases as the rate of shearing increases (Campbell and Brennen, 1983;Hanes and Inman, 1985b).…”

Section: Summary and Discussionmentioning

confidence: 99%

A Model for Scaling Avalanche Speeds

McClung

1990

J. Glaciol.

View full text Add to dashboard Cite

show abstract

“…Later Hwang and Hogg [252] and Brennen et al [253], focussed on examining the diffusive remixing in these flows and illustrated the possibility of granular jumps or bores, respectively. However, due to the lack of intrusive experimental techniques to precisely determine the flow velocity, solid volume fraction and granular temperature, many studies utilised computer simulations as an alternative approach, see [254,255] and references therein. Campbell et al [254,256] were one of the first to compare their particle simulations of twodimensional unidirectional flow of inelastic circular cylinders with experiments.…”

Section: Flows Over Inclined Channels (Chute Flows)mentioning

confidence: 99%

“…However, due to the lack of intrusive experimental techniques to precisely determine the flow velocity, solid volume fraction and granular temperature, many studies utilised computer simulations as an alternative approach, see [254,255] and references therein. Campbell et al [254,256] were one of the first to compare their particle simulations of twodimensional unidirectional flow of inelastic circular cylinders with experiments. They used a hard-sphere DEM approach and observed their results to qualitatively match the findings of Augenstein & Hogg [250] and Bailard [257], but not of Savage [251] and Ridgway & Rupp [247].…”

Section: Flows Over Inclined Channels (Chute Flows)mentioning

confidence: 99%

Polydisperse granular flows over inclined channels

Tunuguntla¹

View full text Add to dashboard Cite

POLYDISPERSE GRANULAR FLOWS OVER INCLINED CHANNELS DISSERTATIONto obtain the degree of doctor at the University of Twente, on the authority of the rector magnificus, Prof. dr. H. Brinksma, on account of the decision of the graduation committee, to be publicly defended on Friday 9 October 2015 at 16:45 hrs by Deepak Raju Tunuguntla born on the 3rd of November 1986 in Hyderabad, India. Granular materialsEverything seems simpler from a distance. -Gail TsukiyamaMatter exists in a variety of forms, of which granular materials -although simplebehave differently from any of the other standard forms (solid, liquid and gas). For example, a sand castle appears like a solid, which when tumbled upon, crumbles down like an avalanche. On a few occasions, this avalanche takes down the whole castle, whereas sometimes it is confined only to a thin layer on its surface (liquid). In another example, shake up some crushed ice in a cocktail mixer and it behaves like a gas, whereas when trying to pour some salt out of an orifice of a jar, the flow tends to choke and gets clogged at the orifice. Granular material has it all, solid, liquid, gas, plastic flow, glassy, etc. -it can mimic all of these behaviours. Thus exhibiting a prime reason for investing our interest in understanding these simple but, mysterious materials. HistoryOur knowledge of granular matter dates back to an era even before mankind's existence. These materials exist on a range of scales -micron sized to planetary -in a variety of forms, exhibiting multitudes of interesting phenomena. The earliest encounter between man and granular matter happened in the surroundings in which he evolved, i.e. with soil, sand, stones, rocks, etc., but more importantly it was his need for survival that ultimately led to an inevitable bond between humanity and granular matter, existing till today. Historical records indicate that primitive men often settled along the river banks where fresh food was available throughout the year. However, due to climatic changes coupled with migration of primitive tribes, new food gathering methods had to be devised. Man needed to find some way to store the nutrients for periods of time when no fresh food was available. Seeds, such as cereal grains, seemed to be one way to solve 1 1 2 Introduction Figure 1.1: Facsimile of a famous scene from a wall painting on the tomb of Djehutihotep, a pharoah (circa 1932(circa -1842. It illustrates his huge monolithic statue being transported from the quarries. In the front of the statue (near the feet) we see a workman pouring water to lubricate the sand, helping the four rows of workmen, 43 men in each, to haul the sledge smoothy (less friction). The figure is adapted from Dowson [1].the storage problems. Ultimately around 8000 BCE, during neolithic revolution, this seed storage led man towards becoming more agriculturally oriented. Grains were likely among the first cultivated crops. They could be grown relatively easily, farmed in surplus quantities and were suitable for storage in harsh cold winter climat...

show abstract

Computer Simulation of Shear Flows of Granular Material

Cited by 43 publications

References 12 publications

Microstructural deformation mechanisms of unsaturated granular soils

Microstructural deformation mechanisms of unsaturated granular soils

A Model for Scaling Avalanche Speeds

Polydisperse granular flows over inclined channels

Contact Info

Product

Resources

About