Identical calibration approach in discrete element method for modeling mechanical properties in fiber- and particle-reinforced composites

This study explores the mechanical properties of particle- and unidirectional fiber-reinforced composite materials using the discrete element method (DEM) with an identical calibration technique. Determining micromechanical properties within DEM modeling is a time-consuming challenge typically requiring a distinct calibration approach for each specific model. In this research, we employ identical micromechanical properties for the generated discrete domain to simulate both types of composites. The findings in this paper suggest that an identical calibration procedure could potentially be effective for modeling composites, regardless of their varied reinforcement shapes. Given the computational costs associated with DEM modeling, this research presents a potential advancement in streamlining the DEM calibration process. The linear parallel-bond model served as the contact model in DEM simulations, offering realistic estimates for materials resembling cemented structures. Additionally, group logic was employed in DEM modeling to construct the reinforcement and matrix phases of the composites. Results were validated through FEM simulations and theoretical predictions, demonstrating a satisfactory level of agreement. Furthermore, this paper provides a comprehensive depiction of micro-crack initiation and propagation, along with various fracture modes, including matrix and fiber cracking, as well as matrix/fiber debonding, for both composite types.