Simulation of load capacity of 3D printed concrete patterns

Abstract: Three-dimensional concrete printing (3DCP) is a technology which has rapidly developed in recent years. The technology is based on a layer-by-layer technique where models are designed in a 3D software program and printed by a robot. Unlike conventional concrete, 3DCP has stricter material requirements due to the absence of formwork. Increased freedom of design and cost-effectiveness are some of the potentials of 3DCP. The technology of 3DCP was first developed in 1997. Today, both houses and bridges have been printed, to mention some. This MSc report aims to increase the knowledge about 3DCP and how printed structures can be evaluated using finite element analysis (FEA). Three patterns were printed with identical material mixture and printing parameters. After 28 days, compressive tests were carried out on the designs. The results of the tests were the basis for the FEA in this thesis. Three models were created using the finite element software, Abaqus, to recreate the behaviour of the printed patterns. The analyses were performed as parametric studies with nonlinear material behaviour, and the models were subjected to compressive loading to failure. The conducted analyses show that some parameters play an important role in the modelling of the concrete patterns. These parameters include Young’s modulus, compressive stress at crushing, and a parameter considering the multi-axial behaviour. Less consideration can however be put into the other parameters affecting the material. This is due to the material failure which was dominated by compressive stress. Using FEA, models can be recreated to resemble 3D printed patterns and their structural behaviour. However, the models presented in this thesis are not fully representative. Further research on the material mixture, the impact of the printing parameters, and 3D printed concrete in its fresh, and curing, state is needed.