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Example of un-realistic and realistic virtual aggregates

Example of un-realistic and realistic virtual aggregates

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An algorithm to re-create virtual aggregates with realistic shapes is presented in this paper. The algorithm has been implemented in the Unity 3D platform. The idea is to re-create realistically the virtual coarse and crushed aggregates that are normally used as a material for the construction of roads. This method consists of two major procedures:...

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... The first step to manufacture virtual particulate materials is to create virtual aggregates. To do so, the shape of particles can be recorded, which can be done by using different acquisition systems as 3D laser scanner, X-ray Computed Tomography, or image acquisition systems, as can be seen in [11] and [12] and [13] respectively. Then, we need to recreate these shapes computationally. ...
... Eleven types of coarse aggregates from different sources and different shape characteristics have been used in this study. These aggregates had been characterised in detail in reference [13], where they have been also classified based on their circularity and sphericity, using the Krumbein chart used for visual evaluation of aggregates. The particles are glass spheres (GS); crushed glass (CG); round gravel (RG); slag (S); five types of Limestone: L1, L2, L3, L4 and L5, with maximum size 20 mm, 6 mm, 10 mm, 14 mm and 20 mm respectively, and two types of granite, G1 and G2, with size 14 mm and 6 mm, respectively. ...
... 1) The median of the: area (A 50 ), perimeter (P 50 ), minor feret (MinFeret 50 ), major feret (MaxFeret 50 ), aspect ratio (AR 50 ), circularity (C 50 ), roundness (R 50 ). A deeper explanation of these concepts can be found in reference [13]. ...
Article
In this paper, an impulse-based Discrete Element numerical Method (iDEM) included in a physics toolbox, has been used to compact virtual aggregates. Firstly, geometrical properties, such as area, aspect ratio, perimeter, minor and major feret, circularity and roundness, of eleven types of coarse aggregates were measured. Then, a mass of each of these aggregates was compacted under vibration. The aggregate packings’ properties, such as aggregate segregation and orientation, porosity, pore -diameter, -tortuosity, -connectivity, -aspect ratio, -circularity, and -vertical distribution, were measured from Computed Tomography scans. Secondly, the aggregates were simulated using a Perlin noise in spherical primitives, which adjusted their geometry until they achieved realistic morphologies and gradations. iDEM detects contacts between complex shapes, including concavities, and computes the interaction between large amounts of complex objects. Results show that the properties from the packing experiments and simulations are highly comparable. This paper demonstrates the capacity of the physics toolbox to simulate granular materials effectively.
Article
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