2.3. Proof of usability

Concrete is regarded as a homogeneous, joint-free material in the construction industry. However, this cannot be assumed for additive manufacturing, since several layers of concrete are build up. Due to the production-related anisotropy, the compressive strength was determined in three load directions. Figure 1 serves to clarify the load directions and the designation. Here, the placement direction is in the X-direction. The installation height in the Z-direction is based on the number and dimensions of the layers. The width of the component in the Y-direction is depending on the width and number of the extrudate. Furthermore, samples were produced in two ways: the concrete was injected directly and extruded into the moulds.