Three-dimension mesoscale model of concrete by random placement algorithm and its failure mechanism analysis

Abstract

This contribution presents the development and application of a 3D numerical concrete model for investigating the fracture behavior of concrete at the mesoscale. The reconstruction of actual geometric models of pebble and crushed aggregates is carried out using a 3D laser scanner. An aggregate and pore library were then constructed, and a 3D random placement method is developed to generate the realistic mesostructure of concrete. Additionally, the cohesive zone model-based numerical computation approach was employed to simulate the fracture problem in concrete. Then, the numerical concrete model is applied to investigate the mechanical response and fracture behavior of cylindrical concrete specimens under uniaxial compression and concrete beams under three-point bending. Results show that the 3D mesoscale concrete model effectively captures the complex fracture process and nonlinear mechanical behavior. This methodology can be used for investigating the effect of mesostructure on macroscopic behavior of concrete and also has potential applications in studying the behavior of particulate composites under various conditions.