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Powders & Grains 97 PROCEEDINGS OF THE THIRD INTERNATIONAL CONFERENCE ON POWDERS & GRAINS DURHAM/NORTH CAROLINA/18-23 MAY 1997 Powders & Grains 97 Edited by ROBERT P. BEHRINGER Duke University, Durham, North Carolina, USA JAMES T.JENKINS Cornell University, Ithaca, New York, USA UNIVERSITATSBIBLIOTHEK HANNOVER TECHNISCHE INFORMATIONSBIBLIOTHEK A. A. B ALKEMA / ROTTERDAM / BROOKFIELD /1997 Powders & Grains 97, Behringer & Jenkins (eds) © 1997 Balkema, Rotterdam, ISBN 905410 884 3 Table of contents /Z, ft i> 6 ^ Preface XIII Keynote lecture Avalanches of granular materials 3 P.G.de Gennes Industrial and field studies Unto dust shalt thou return 13 B.J.Ennis Discrete particle simulation of dispersed gas-solid flows 25 Y.Tsuji Viscoelastic coalescence of spherical particles 31 AJagota, CArgento & S. Mazur Compaction of a granular packing with a lubricant 37 O.Pitois, P.Moucheront, C.Weill & J.-KRoux Process modeling and design for colloidal powder forming 41 C-W.Hong Fluid dynamics and phase separation in the uniaxial compaction of powders 45 D. B. Nicolaides Industrial research needs in the development and processing of products having 49 concentrated paniculate phases MJ.Adams Dynamic behavior of sand under S. H. P B. loading 53 J.F.Semblat, M.P.Luong & G.Gary The in-situ characterization of mechanical properties of granular media with the help 57 ofpenetrometers R.Gourves, EOudjehane & S.Zhou Why prediction of grain behavior is difficult in geological granular systems 61 P.K.Haff Effect of particle size on instantaneous pressure in pulse-stabilized fluidization 65 D.EBeasley & D.V.Pence Liquefaction: A phenomenon specific to granular media 69 EDarve&O.Pal Liquefaction characteristics of very loose Hostun RF sand in triaxial compression 75 and extension E.lbraim & T.Doanh Sand motion and permeability changes induced by filter flows 79 S.B.Grafutko & V.N.Nikolaevskiy Wall friction measurement for sugar crystals 83 M.P.Luong Effect of micromechanical parameters on stresses and displacements in an ensiled granular 87 material using the Distinct Element Method S. Masson & J. Martinez Mechanism governing the relationship between solids and gas rates in pneumatic conveying 91 at low and very low velocities S.Laouar & Y.Molodtsof Two phase flows in granular materials: Particle-particle and particle-fluid interaction 95 KB. Pitman The characteristics of 'material-wall interactions' in silo during emptying: Flow pattern 99 and pressure distributions B.Yacoub&J.C.Roth Powder compaction, agglomeration, and fracture Evolution and modelling of porosity and specific surface area of pharmaceutical tablets 105 during compaction J.CMasteau, G.Thomas, D.Chulia & M.Deleuil The packing of fine, cohesive powders 109 P. K.Watson, H. Mizes, ACastellanos & A Perez Discrete element modeling of fabrication flaw precursors in the compaction of agglomerated 113 ceramic powders D.R.Greening, G.G.IKMustoe & G.LDePoorter Experimental characterization and modelling of the densification of powder mixtures 117 F.Delie & D.Bouvard Mechanical properties and attrition resistance of porous agglomerates 121 D.Bortzmeyer Steel powder forming analysis by smooth particle method 125 S.Tamura & T.Aizawa Effects of particle size and bond strength on impact breakage of weak agglomerates 127 ZNing, R.Boerefijn, M.Ghadiri & CThornton VI Fracture of particulate solids 131 C.Thornton, M.T.Ciomocos, K.K.Yin & M.J.Adams The shear fracture of a tilted layer of cohesive powder 135 J. M. Valverde, A Ramos, A. Castellanos &P.K. Watson Numerical modelling of the mechanical behavior of non spherical, crushable particles 139 A Mahboubi, B. Cambou & J. -J. Fry The strength of granules produced from fine powders 143 P.J.Denny Effects of humidity on quasi-static behavior of granular media 147 N. Fraysse, H. Thome & L. Petit A disc centrifuge for the study of flow processes in cohesive granular materials 151 F.CGenovese, P.K.Watson, ACastellanos & A Ramos Effect of shear strain rate on attrition of particulate solids in a shear cell 155 M.Ghadiri&ZNing A microscopic simulation of oblique collisions of 'wet' agglomerates 159 G.Lian, C.Thornton & M.J.Adams Tensile strength and void fraction as functions of consolidation stress for a set of xerographic 163 toners /. M. Valverde, A Ramos, A Castellanos &P.K. Watson Quasi-static deformation Attractors, percolation thresholds and phase limits of granular soils 169 G.Gudehus Problems in the statics and dynamics of granular materials 185 S. B. Savage The stress-strain behavior of granular materials under shearing based on the mechanism 195 of fabric change SYamamoto & H.Matsuoka Statistical homogenization for granular media - Application to non linear elastic modelling 199 Ph.Dubujet,B.Cambou, F.Dedecker & F.Emeriault A micro mechanical model for overconsolidated behaviour in soils 203 G. R. McDowell & M. D. Bolton Importance of particle rotation in the mechanics of granular materials 207 M.0da, Klwashita & T.Kakiuchi Force networks in dense granular media 211 F.Radjai,D.E.Wolf S.Rowc,M.Jean & J.J.Moreau Contact disorder and nonlinear elasticity of granular packings: A simple model 215 J.-N.Roux VII A micromechanical comparison between experimental results and numerical simulation 219 of a biaxial test on 2D granular material D.Daudon, J.Lanier & M.Jean Uniaxial compression of granular media: Numerical simulations and physical experiment 223 C.Thornton & J.Lanier On arching in dry granular materials 227 R.Peralta-Fabi, C. Malaga & R.Rechtman Elastoplastic arching in 2D granular heaps 231 F.Cantelaube & J.D.Goddard Fabric and contact parameters for sand from wave velocity measurements 235 F.Emeriault & C.S. Chang Inelastic behavior of random arrays of identical disks 239 J.T.Jenkins & M.AKoenders Linear and non-linear elasticity of granular media: Stress-induced anisotropy of a random 243 sphere pack D. L. Johnson, L. M. Schwartz, D. Elata, J. G. Berryman, B. Hornby &AN. Norris Discrete and continuum models in the mechanics of granular materials 247 D.Harris Analysis of micro-variables through entropy principle 251 KBagi Classification of granular materials 255 J.Biarez, S.Taibi & R.Sa'im Numerical estimation of the elastic properties of cemented granular materials 259 with microstructure LBojtdr Numerical simulation of the amorphous interfacial material behaviour 263 A Ghaouti, M. Chaze, Ph. Dubujet, F. Sidoroff & B. Cambou Grain convection and diffusion in a 2-D embankment under slow cyclic deformation 267 P.Evesque Damage and fatigue modeling for bonded particulate materials 271 C.S. Chang Evolution of microstructure in granular materials: Experimental results 275 J.Lanier & F.Calvetti The yield surface of granular materials determined by the fabric 279 H.Matsuoka, K.Kawase, K.Itoh & Y.Akashi Yield conditions of an assembly of disks subjected to a deviatoric stress system 283 L. Oger, S. B. Savage, D. Corriveau & M. Sayed Vorono'i tessellation of packings of equal spheres 287 L. Oger, J. P. Troadec, P. Richard, A Gervois & N. Rivier VIII Calculation of the effective moduli of a random packing of spheres using a perturbation 291 of the uniform strain approximation AC. Paine Stress distribution in an inclined pile: Soil mechanics calculation using finite element 295 technique P.Evesque & S.Boufellouh New statistical measures for analysis of granule assemblies 299 M.Satake Arching effects in the stress distribution of sandpiles 303 J.PWittmer, M.ECates, P.Claudin & J.-P.Bouchaud Simplified tangential force-displacement models for a discrete element particle flow code 307 L.Lesburg,X.Zhang, L.Vu-Quoc & O.R.Walton Contact of rough elastic spheres: A simplified analysis 311 J.C. Wells Stress fluctuations Intermittency and self-similarity in granular media 317 H.J.Herrmann Intermittences in the compression process of a model granular medium 321 A. Ngadi, J. Rajchenbach, E. Clement & J. Duran Models for stress fluctuations in plasticity 325 M.Shearer & D.G.Schaejfer Sensitive force measurements in a sheared granular flow with simultaneous imaging 329 S.Nasuno,AKudrolli&JP.Gollub Stress fluctuations for sheared 3D granular materials 333 R. P. Behringer & B. Miller Fluctuations and dynamics for a two-dimensional sheared granular material 337 D.Howell & R. P. Behringer Hydrodynamic fluctuations and averaging problems in dense granular flows 341 C.Saluefia, S.E.Esipov & T.Poschel Stress distributions in a two dimensional granular material 345 G.W.Baxter Fluctuating aspects of the pressure in a granular column 349 E.Clement, Y.Serero, J.Lanuza, J.Rajchenbach & J.Duran Modelling techniques for granular media using small assemblies 353 M.AKoenders Metastability and instability in model grain piles 357 S.Sen&S.Pal IX Plane waves and dynamic ill-posedness in granular media 363 V.AOsinov Vibrated beds Stripes, squares, hexagons, and localized structures in vertically vibrated granular layers 369 H.L. Swinney, F.Melo &P.B. Umbanhowar Surface waves and pattern formation in vibrated granular beds 373 S.Luding Studies of granular compaction 377 E.R.Nowak, M.Povinelli, H.M.Jaeger, S.R.Nagel, J.B.Knight & E.Ben-Nairn Vibrofluidized beds of solid granules: From experiments to hydrodynamic model 381 AGoldshtein & M. Shapiro Size-dependent segregation in a 3D vibrated bed 385 L Vanel, A D. Rosato & R. N. Dave Size-segregation and mixing effects in audio-fluidised binary powders 389 J. Castle, A Mar land & L. V.Woodcock NMR measurements demonstrate increased intensity of collisions near walls in a vibrating 393 granular material V.Yu. Kuperman Wavy instability in shaken sand 397 E.van Doom & R. P.Behringer Sand behaviour in cavity filled with liquid and sumitted to horizontal vibrations 401 P.Evesque, A Ivanovo, V.Kozlov, D.Lyubimov, T.Lyubimova & B. Roux Convection due to horizontal shaking 405 KLiffman, G.Metcalfe & P.Cleary Chaos in one-dimensional granular flows with oscillating boundaries 409 D. Blackmore & R. Dave Vertical vibrations of granular materials between two parallel horizontal walls 413 J. M. Bourinet & D. Le Houedec Two hydrodynamic models of granular convection 417 H.Hayakawa & D.
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