Enhancing Geotechnical Performance Using Bio-Inspired 3D-Printed Particles: A Study on Shear Strength Behavior

Abstract

This study investigates increasing the shear strength of granular materials by utilizing small, 3D-printed particles of engineered geometry. Instead of ordinary soil additives, small percentages of bio-inspired particles with an internal honeycomb structure were included in a base material of flat, polished marble. The objective was to test effects of various proportions of 3D-printed inclusions on the two major shear strength components: cohesion (c) and internal friction angle (φ). Three mixtures were prepared: pure marble (0%), marble with 2% 3D-printed particles by weight, and marble with 3% 3D-printed particles. A direct shear test was conducted under controlled normal stresses, and resulting shear stresses were measured to calculate c and φ. The addition of 2% and 3% of 3D-printed particles markedly increased both c and φ due to the honeycomb geometry and interlocking ability, which enhanced contact points and load transfer. the 3% exhibited no further improvement, and overall performance was slightly lower than that of the 2% mixture. This behavior is most likely a result of slight bunching of the particles and decreased packing efficiency. This result indicate that increasing the content beyond an optimal value does not necessarily improve performance, and the importance of achieving the suitable proportion.