China
Africa
Explore chapters and articles related to this topic
Wave Propagation in Granular Medium
Published in Srinivasan Gopalakrishnan, Elastic Wave Propagation in Structures and Materials, 2023
According to Wikipedia [61], a granular material is a conglomeration of discrete solid, macroscopic particles characterized by a loss of energy whenever the particles interact (the most common effect of interaction is the friction caused by colliding grains). The size of the grains vary across different materials with the lowest grain size limit being 1μm. Some examples of granular materials are the snow, nuts, coal, sand, rice, coffee, corn flakes, fertiliser, and bearing balls. Understanding of elastic wave propagation in granular medium is very important in many disciplines such as geotechnical, geophysical, oil exploration and also in army applications such as sand bunker designs. In this chapter, among all the granular material, we will study the propagation of elastic waves only in dry sands.
Granular Materials Powder Metallurgy
Published in Leo Alting, Geoffrey Boothroyd, Manufacturing Engineering Processes, 2020
A granular material is a mixture of solid grains or particles possibly of varying sizes. Each grain or particle may be a combination of smaller units, for example, the crystals in metal grains. Granular materials are generally used for one or more of the following reasons: The particular material is only available or can only be produced in the granular state.The desired properties (porosity, combination of materials, etc.) can only be obtained from granular materials.Manufacture of the product is cheaper than by other methods.Small components are difficult to produce by other methods.
Measuring stiffness of soils in situ
Published in Fusao Oka, Akira Murakami, Ryosuke Uzuoka, Sayuri Kimoto, Computer Methods and Recent Advances in Geomechanics, 2014
Fusao Oka, Akira Murakami, Ryosuke Uzuoka, Sayuri Kimoto
By invoking the Mohr-Coulomb failure criterion for cohesionless material, the following stress condition is satisfied everywhere in a sand heap. For non-compacted granular materials, the angle of repose is equivalent to the angle of shearing resistance.
A criterion to quantify the effect of superheavy vehicles on asphalt pavements based on layers deformation
Published in International Journal of Pavement Engineering, 2022
Erdrick Leandro Pérez-González, Jean-Pascal Bilodeau, Guy Doré
Granular materials exhibit a non-linear behaviour within the elastic range. Given this, the non-linear Uzan constitutive model for the resilient modulus () of granular materials is used in the i3C-SHL, as described in Equation [3] (Doré and Zubeck 2009, ARA Inc 2019): With, Where, is the resilient modulus, is the bulk stress, is the octahedral shear stress, is the reference pressure (100 kPa), , and are experimentally determined constants specific to materials and conditions.
Scale-up in Turbula® mixers based on the principle of similarities
Published in Particulate Science and Technology, 2020
Claire Mayer-Laigle, Cendrine Gatumel, Henri Berthiaux
Granular materials are present in numerous processes, in all industrial sectors. In many of them, mixing or premixing of dry particles is a critical step since it controls the properties of the finished product (color, taste, bioavailability of a drug) (Shenoy et al. 2015). It can influence the downstream steps (Zhou and Morton 2012), as for example, in dry lubrication processes (Suzuki et al. 2015). At the process scale, granular materials can be seen as a state of matter at the crossroad between the solid and the liquid states (Redaelli et al. 2017). Granular materials appear as a multitude of grains, behaving as a solid in isolated form and exhibiting internal discontinuities, according to the size, the shape, and the nature of the interactions (Shah et al. 2017). These discontinuities induce a partial transmission of the stresses during the process, making the behavior of the raw material difficult to describe, flowing sometimes as a liquid or aggregating under the form of clusters (Savage 1984).
Numerical simulation of the reinforcement effect of rock bolts in granular mixtures
Published in European Journal of Environmental and Civil Engineering, 2019
Chao Hu, Hua-kang Zheng, Wei Zhou, Gang Ma, Lei Hu
Granular materials are widely involved in geotechnical engineering, for example, crushed rock mass, natural gravel, rockfill in slopes, underground caverns, hydraulic structures, etc. Granular materials are complex discontinuous media. To increase the stability of granular materials, rock bolts can be used. Good design of rock bolts can effectively control the deformation. It has become an economic and effective method to improve the stability in geotechnical engineering. Furthermore, the use of rock bolts is one of the most common reinforcement methods. However, the current knowledge does not supply satisfactory information for reasonable and systematic design. Therefore, further studies of the rock bolt reinforcement mechanism in granular mixtures and its effects are needed.