Off-site 3D printed concrete beam design and fabrication
Bjorn Ter Haar, Jacques Kruger, Gideon van Zijl
Abstract
This study identifies the need for a prefabricated reinforced 3D printed concrete (3DPC) beam that can integrate into a building system. A novel 3DPC beam for a specified target structure is designed, fabricated, and experimentally tested. The beam design is experimentally investigated by fabricating the beam with design-determined print parameters and performing a set of two large-scale 4-point bending tests which determine the shear and flexural resistance of the beam. Modified Eurocode design equations successfully predict the flexural resistance within 6%, however the shear design equations overpredict the shear resistance by 51%. The study provides a replicable design and fabrication workflow for 3DPC elements, and a feasible 3DPC beam concept that requires shear strengthening before application in the target frame. 3D concrete printing designers are provided with a 3DPC beam solution with the potential to integrate into a building system and are further equipped to design and fabricate future 3DPC building elements.