(262e) Photoelastic Properties of 3D Printed Particles

3D printing can be used as a means to unlock new advances in research, particularly for particle applications. Our project investigates the photoelastic behaviour of 3D printed particle structures, to determine whether 3D printed particles can be used for stress visualisation experiments. The compression of simple spherical disc shapes to complex multiple stacked disc designs were printed using a Statasys Objet printer using VeroClear material, which is photoelastic. Compression experiments were carried out using an Instrom in a darkfield configuration to observe the stress fringes. The compression of the particles at 2mm/min were video recorded. The time lapse of the compression revealed stress fringes and force chains, similar to the previous conventional methods. It was found that complex structures fail sooner under heavier load. Furthermore, the effect of printing layer was found to have a minor effect on the photoelastic behaviour of the particle. Further work is underway to plot the exact strain distribution of the design using Digital Image Correlation (DIC) and Finite Element Analysis (FEA) to confirm the accuracy of the stress fringes. The work demonstrates that visualisation of stresses in more complex shapes can be successfully conducted using 3D printing techniques.