Cyclic Behavior of Physical Models of Reinforced Concrete Columns Built with Additive Manufacturing

Abstract

This paper presents quasistatic cyclic tests on 1∶30 scale physical models of reinforced concrete columns with additively manufactured (3D-printed) reinforcement cages. Such physical models are useful for centrifuge modeling of RC structures focusing either on soil–structure interaction problems or on the statistical validation of system-level assumptions of numerical models used in earthquake engineering. A gypsum-based model concrete was used, because at such scales it can better model the tensile strength of concrete and the bond between concrete and reinforcement. Specimens of different reinforcement and axial load were tested and compared with a database of 197 full-scale rectangular RC columns that failed in flexural mode. Additionally, numerical models were built using the OpenSees platform, and their outcomes were compared with the experimental tests. It was found that the tested columns behaved similarly to full-scale columns in terms of strength, stiffness, and ductility observed in full-scale columns. Moreover, strain penetration was physically modeled more accurately, which eliminated the premature fracture of rebars observed in previous studies. Finally, the comparison between the numerical models and experimental results demonstrated that the component-level behavior of the tested columns can be predicted using commonly employed numerical modeling methods typically used for modeling RC structures.