Multi-scale assessment of the structural performance of 3D printed concrete

3D concrete printing (3DCP) has sparked a lot of interest in the concrete research community worldwide, because of the many possibilities that exist in design and fabrication of complex structures. Among other aspects, the determination of index properties governing the structural performance has been a major challenge for 3DCP. Unlike conventional concrete, where standard specimens can be mould cast to determine the response to different types of loading, the presence of interlayer joints in 3DCP leads to uncertainties regarding the representative volume element that should be considered for testing. As a result, there exist a number of methodologies around the world for assessment of the strength and modulus of 3D concrete, and no distinct standardization strategy has been universally accepted. This presentation explores the assessment of compressive loading performance of 3D printed concrete, from small scale specimens to full scale wall panels. The results indicate that there is a significant difference in performance at different scales, which is further complicated by the inclusion of infill material in the cavities of the 3D printed segments.