Additively manufactured steel reinforcement for small scale reinforced concrete modeling: Tensile and bond behavior

Abstract

Small scale (∼1:30–1:40) Reinforced Concrete is useful for centrifuge testing. However, manufacturing the reinforcing cages by hand at this scale is practically difficult. This paper suggests that small scale reinforcement can be manufactured using a metal 3D printer. Mechanical properties of 3D printed submillimeter rebars are discussed and compared to properties of typical prototype rebars. Different model concrete mix designs are tested to identify optimal mixes. Pullout tests of rebars with different surface rib configurations embedded in different concrete mixes are discussed.Based on the test results, by modulating the printing parameters it seems feasible to obtain 3D printed submillimeter bars that can be used as physical models of prototype rebars. A gypsum-based model concrete was more similar to prototype concrete than cement-based mixes. Most importantly, bond slip behavior that is comparable to full-scale concrete could be achieved, something that is vital and has never been reported before.

Keywords

• Additive manufacturing
• Centrifuge testing
• Physical modelling
• Small-scale models
• RC structures
• Bond