Numerical Modeling of an Extrusion-Based Concrete Printing Process Considering Spatially and Temporarily Varying Material and Process Parameters

Abstract

During the past few years, additive manufacturing techniques for concrete have gained extensive attention. In particular, the extrusion-based 3D concrete printing exhibited a rapid development. Previous investigations are mostly based on experimental studies or even trial-and-error tests. A more profound understanding of the relationships between the process and material parameters and the manufactured structure can be advanced by numerical modeling and simulation. It enables to study a wide range of parameters such that dependencies of properties of the printed product on different influencing factors can be identified. Taking into account the uncertain nature of process and material parameters of the extrusion-based concrete printing, the process can be reliably controlled and finally optimized. The presented study uses a pseudo-density for a finite element based modeling approach. The pseudo-density determines the properties of the individual finite elements, analogous to the soft-killing method of topology optimization. Layer by layer the previously created elements are activated. Material parameters are described as temporally and spatially variable to reflect the temporally variable printing process. First results of a reliability estimation are shown for a 2D modeled additively manufactured wall.