Investigation on the flexural and tensile performance of 3D printable cementitious mixtures considering the effect of fiber distribution

Abstract

This study aims to investigate the orientation distribution of steel fibers in 3D printed concrete. The effects of steel fiber dosage (0.0%, 0.5% & 1.0% by volume) and print speed (40 mm/s & 80 mm/s) on fiber distribution was obtained using optical microscopy in conjunction with digital image processing and a mathematical equation extracted from a trained artificial neural network model. Better fiber orientation results (within 0 – 40 degrees) is achieved while printing at 40 mm/s with 0.5% fiber dosage by volume. The compression, split tensile and flexural tests are also performed and correlated with fiber distribution. The addition of steel fibers increased the compressive, flexural, and split tensile strengths of 3D printed samples up to 24%, 143%, and 63%, respectively.