Abstract
A numerical model was developed to analyse the mechanical behaviour of fresh, 3D printed concrete, in the range of 0 to 90 min after material deposition. The model was based on a time-dependent Mohr-Coulomb failure criterion and linear stress-strain behaviour up to failure. An experimental program, consisting of unconfined uniaxial compression tests and direct shear tests, was set-up and performed to obtain the required material properties. The material tests showed that the Young's modulus and cohesion linearly increase with fresh concrete age, as do the compressive and shear strength. The Poisson's ratio and angle of internal friction, on the other hand, remain constant. Subsequently, the model was validated by comparison to printing experiments. Modelling of the printed samples reproduced the experimental results qualitatively, but the quantitative agreement with the print experiments could be improved. However, the deviations can well be explained and the type of failure-deformation mode was predicted accurately.
| Original language | English |
|---|---|
| Pages (from-to) | 103-116 |
| Number of pages | 14 |
| Journal | Cement and Concrete Research |
| Volume | 106 |
| Issue number | April 2018 |
| DOIs | |
| Publication status | Published - 9 Feb 2018 |
Funding
The support of the staff of the Structures Laboratory Eindhoven is greatly acknowledged. The assistance in the 3DCP research of Master track students Structural Design at the TU/e Department of the Built Environment is highly valued. For this paper, the authors appreciate the work of T. Krijntjes, J. Hermus and C. Maas in particular, on whose MSc project the material presented is partially based. The TU/e research program on 3D Concrete Printing is co-funded by a partner group of enterprises and associations, that on the date of writing consisted of (alphabetical order) Ballast Nedam, BAM Infraconsult bv, Bekaert, Concrete Valley, CRH, Cybe, Saint-Gobain Weber Beamix, SGS Intron, SKKB, Van Wijnen, Verhoeven Timmerfabriek, and Witteveen+Bos. Their support is gratefully acknowledged.
Keywords
- 3D printing
- Experimental validation
- Finite element modelling
- Fresh concrete
- Mechanical properties