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Showing 1 to 20 of 108 for “"granular materials"”.
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Computational modeling of granular materials
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996.
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Three -Dimensional Discrete Element Simulation for Granular Materials
BLOKS3D is parallelized with OpenMP on NCSA supercomputers to seek higher computational speed, and a speed up ratio of 3∼5 has been achieved. The largest size simulations involve more than 97,000 particles.
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Discrete element models for granular materials and rock masses
… several types of geotechnical problems involving granular materials and rock masses, which are intractable with conventional methods, based on continuity assumptions.
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Direct computation of the packing entropy of granular materials
Granular materials are the second most manipulated material in industry after water and their properties are of great importance for the pharmaceutical, food, mechanosynthesis and semiconductor industries. Up to 60% of the capacity of some industrial plants is used to process them. This thesis …
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Spreading of viscous fluids and granular materials on slopes
Materials can flow down a slope in a wide range of geophysical and industrial contexts, including lava flows on volcanoes and thin films on coated surfaces. The aim of my research is to provide quantitative insight into these forms of motion and their dependence on effects of the topography, the …
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A nondimensional model for axial digging in granular materials
… the mechanics of thin diggers in a packing of granular materials. Experiments were conducted by pushing diggers of varying thickness into the granular packing and recording the force-depth data. The digger is modeled as a column in buckling; its column effective length factor is calculated. We …
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Permanent Deformation Behaviour of Unbound Granular Materials in Pavement Constructions
… level of permanent deformations in the unbound granular layers (UGL) in pavement constructions under consideration of the seasonal effects. From this data a serviceability limit line (plastic shakedown limit) stress boundary for the unbound granular materials (UGM) was defined for different …
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Design and fabrication of granular materials for surface acoustic waves
Granular materials with structural discreteness and periodicity can lead to novel propagation behaviors of mechanical waves. Acoustic studies of granular media typically involve macroscopic particles whereas contact-based vibrations of microparticles remain largely unexplored. The adhesion which …
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A laboratory study of the friction behavior of granular materials
… boundary conditions used by numerical models of granular friction. The effect of relative humidity (RH from <5% to 100%) is investigated with velocity stepping tests (10-20 tm/s) and slide-hold-slide (SHS) tests (3-1000 s) on 3 mm thick layers of quartz powder, alumina powder, Westerly granite …
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Stochastic and deterministic dynamics investigation of the microstructure of granular materials
Granular materials are ubiquitous in one's daily life. They can be found in the cereal you eat, the sugar you put in your coffee or the sand you walk on in the beach. The study of granular materials has a rich history dating back to the 17th century where Kepler studied the packing of particles. …
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Three-Dimensional Discrete Element Simulation of Granular Materials Using Polyhedral Particles
*This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Microsoft Office.
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Wave tailoring granular materials: effect of randomness and plane wave propagation
… as practical significance of impact response in granular media. In the first part of the study, we investigate numerically the effect of randomness in material and geometric properties on wave propagation behavior in 1D and 2D granular media. Results obtained for both 1D chains and 2D media show …
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Permanent deformation behavior of unbound granular materials and rutting model development
… properties. Sixteen (16) different unbound granular materials commonly used in the state of North Carolina (NC) for pavement subbase/base applications were used in this study. The goal was to accurately estimate the field performances of aggregate base courses through development of a new …
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Experimentally validated DEM modelling of granular materials under simple shear testing
… testing method to study the response of granular materials under uni-directional and multi-directional loading. DEM modelling provides complementary information such as contact networks and particle movements, that is underlying, but not observed directly from the experiments. In this …
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Localization and instability in sheared granular materials: role of friction and vibration
… instabilities have been long observed in sheared granular materials. Yet, their microscopic underpinnings, interdependencies and variability under different loading conditions have not been fully explored. Here, we use a non-equilibrium thermodynamics model, the Shear Transformation Zone theory, …
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Constitutive equations for granular materials : application to dry sand and powder metal
… the complete process of strain localization in granular materials have been previously reported. Predictions for the onset and process of shear band formation are critically dependent upon the constitutive equations employed. In this thesis, a new physically based constitutive model is …
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Influence of physical characteristics on the mechanical and dynamic parameters of granular materials
La présente étude examine de plus près les impacts potentiels des paramètres physiques et mécaniques des sables sur les corrélations théoriques et empiriques existantes les plus célèbres entre les résultats des essais de pénétration dynamique in situ et la vitesse de l'onde de cisaillement des …
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Influence of some particle characteristics on the small strain response of granular materials
… representing the small strain response of geomaterials are the very small strain shear modulus, Gmax, shear modulus degradation G/Gmax, and damping ratio. These are also important parameters in the design of foundations where only small deformation takes place. A review of the literature …
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