Determining the Effect of Geometric and Dynamic Properties of Screws on Fiber-Orientation During FRC 3D Printing Based on Discrete Element Simulation (2024-06)¶

There is growing interest in 3D Fiber Reinforced Concrete (FRC) printing. The orientation of fibers will affect the mechanical properties of printed components, so it is necessary to study the influencing factors of fiber orientation. Currently, there is limited research utilizing numerical simulation to investigate the 3D FRC printing process. This study used the Discrete Element Method (DEM) to simulate the screw extrusion process of FRC in 3D printing. It explored the impact of screw geometry and dynamic parameters, such as printing speed, screw rotation speed, nozzle size, screw blade spacing and printing height, on fiber orientation. Additionally, X-ray micro-Computed Tomography (X-CT) is employed to validate the tendency of fibers in the printed samples to align in the printing direction. Variance analysis was used to reveal the degree of influence of each factor on fiber orientation, and a multiple linear regression model was established to predict fiber orientation.