A study of mortar mixture and flexural strength of mortar beam manufactured by using 3D printing technology

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Abstract
This article aims to study mortar mixture and the flexural strength of mortar beams manufactured by 3D printing technology. The mixture of 3D printing mortar was prepared from hydraulic cement blended with 15.0% calcium stearate by weight. Micro polypropylene (PP) fibers with 6 and 9 mm in length were incorporated at the ratios of 0.1%, 0.2%, and 0.3% by volume. The fresh and hardened properties of mortar were evaluated in order to determine the suitable mixture for building 3D printing beam. Flexural strength of 3D printing beam was determined by three point loading test and results was compared with the finite element method. The results indicated that the mortar containing 6 mm micro- polypropylene fibers at 0 .2% by volume was the suitable mixture for 3D printing technology. Furthermore, when comparing the maximum load and tensile strain values obtained from experiment with the finite element method (FEM), the results from FEM were slightly higher than the test results by approximately 4.3% and 26.1%, respectively.