Three-dimensional mesoscale modeling of concrete with convex aggregate based on motion simulation

摘要

Numerical simulation using a mesoscale model is an effective method to determine the complex mechanical behaviors of concrete. Establishing a numerical sample with a mesostructure close to realistic concrete is crucial for mesoscale simulation. This paper presents a heuristic packing algorithm for constructing 3D random aggregate models with high aggregate content. In the algorithm, the aggregate packing problem is considered as a problem of optimizing the potential energy of the mesoscale configuration. In the initial state, all aggregate particles are randomly placed inside the specimen container; then, the particles move in the container according to the proposed motion simulation strategy until a feasible spatial configuration is obtained. The framework is suitable for various types of aggregates, including spherical, ellipsoidal, polyhedral, and mixed-type aggregates, that have a support mapping representation. In this study, numerous samples with different types of aggregates were established, and the influence of the aggregate gradation on the packing density was examined. The results verified the efficiency and robustness of the proposed algorithm. (C) 2021 Elsevier Ltd. All rights reserved.