MATERIAL TESTING OF MICRO-CONCRETE AND 3D-PRINTED REINFORCEMENT FOR USE IN SMALL-SCALE SEISMIC TESTING OF RC STRUCTURES

A framework for small scale modeling of RC structures that helps understanding their seismic behavior is discussed in this paper.The framework includes testing of small scale RC buildings manufactured using micro concrete and additively manufactured (3D printed) reinforcement cages on a shake table mounted on a geotechnical centrifuge.This paper presents material level testing of micro-concrete and 3D printed reinforcement that are to be used in the proposed framework.Mechanical properties of the 3D printed rebars are first discussed and compared to full scale rebar mechanical properties.A Concept Laser M2 Laser Powder Bed Fusion (LPBF) printer is used for printing the rebars.In addition, the compressive and tensile behavior of micro-concrete are studied using small scale cylinders and beams (for four-point bending tests), respectively.The results of this paper reveal that the mechanical properties of 3D printed submillimeter rebars can be adjusted by modulating the printing parameters.Moreover, concrete mechanical properties that are suitable for the discussed framework can be achieved.