Technical Article: "DMYB Special – Formulating 3D-Printing Mortars"

Author: Klaus Bonin, Wacker Chemie AG, Burghausen Germany

Published in: Drymix Mortar Yearbook, 3D Special, 2019

Specimen made by 3D concrete printing technology.

Abstract:

This article describes how the performance of mortars containing polymer fibers can be improved by adding polymer binders and how polymeric binders can help in the development of formulations for 3D printings.

The use of fibers in construction materials is current practice. Short-cut fibers are often used to change and control the rheology of machine-applied mortars. Polymer binders typically improve adhesion to the substrate and lower the modulus of elasticity.

A new test method for investigating the effect of polymer binders on the bonding of fibers in concrete shows a very strong interaction between the polymer fibers and the VAE polymer used. The polymer binder has a high affinity for the polymer fiber material, which enables the production of a composite material that clearly increases the mechanical anchorage to the lower layer and the final tensile strength and stability of a printed structure.