Magnetic Alignment of Microsteel Fibers as Strategy for Reinforcing UHPFRC

Authors

DOI:

https://doi.org/10.52825/ocp.v1i.79

Keywords:

UHPFRC, magnetic fiber alignment, sustainability

Abstract

The objective of this paper is to provide an insight into current basic research at ITE on the manufacturing process of resource-efficient components through the controlled, automated magnetic distribution and alignment of steel fibers in UHPFRC (Ultra-High Performance Fibre-Reinforced Concrete). The method for distributing and aligning steel fibers in UHPFRC is based on the physical phenomenon of magnetism. Since steel fibers are ferromagnetic, magnetic fields can selectively change their position in the fresh concrete and align them according to the force flow and the maxim "form follows force". The magnetic fiber alignment (MFA) process developed on this principle combines the capabilities of digital and automized component manufacturing with the potential of targeted fiber alignment to increase the material efficiency of UHPFRC. It is highlighted at four levels: UHPFRC

At the material level, studies were conducted on the composite properties of different brand-new and recycled microsteel fibers (MSF), formwork designs suitable for the MFA process were developed, flux densities of different magnets were simulated with special software solutions and measured in practice, and an end effector was fabricated that was implemented on 3- and 6-axis kinematics. At the process level, the interaction of the main parameters of the MFA process was evaluated by visual analysis on transparent glucose syrup-based solutions, and series of specimens were analyzed by micro-CT scans. At the component level, centric tensile tests were performed on a wide variation of dog-bones to provide an assessment of the potential increase in tensile performance of UHPFRC by the MFA process. At an economic and environmental evaluation level, the results from the tensile tests were used to assess and quantify the potential savings from reducing the fiber content and using recycled steel fibers.

References

M. Schmidt and E. Fehling, Eds., Entwicklung, Dauerhaftigkeit und Berechnung ultra-hochfester Betone (UHPC): Forschungsbericht DFG FE 4971-1. Kassel: Kassel Univ. Press, 2005.

Nachrichten — SPP 1542. [Online]. Available: https://spp1542.tu-dresden.de/ (ac-cessed: Sep. 30 2021).

L. Ledderose, S. Lehmberg, H. Budelmann, and H. Kloft, “Robotergestützte, magneti-sche Ausrichtung von Mikro-Stahldrahtfasern in dünnwandigen UHPFRC-Bauteilen,” Beton- und Stahlbetonbau, vol. 114, no. 1, pp. 33–42, 2019. https://doi.org/10.1002/best.201800083

Ledderose, L.; Kloft, H.: Snap-fits made of reinforced concrete: From advanced man-ufacturing to novel applications. Conference: Proceedings of the IASS Symposium “Creativity in Structural Design”. 16.-20.7.2018, Boston, 2018.

Ledderose, L.; Kloft, H.: Preliminary Investigations for Magnetic rearrangement of Steel Fibers in UHPFRC. Conference: Proceedings of the IASS Symposium „Shells, Membranes and Spatial Structures: Footprints.“, 15.-19.9.2014, Brasil, 2014.

Ledderose, L.; Kloft, H.: Robot-aided rearrangement of steel fibres in UHPFRC via magnetic forces. Conference: Future Visions – Proceedings of the IASS Symposium 2015 & ISOFF Symposium, 17.- 20.8. & 16.- 17.8.2015, Amsterdam, 2015, paper No. IASS2015-517423, S. 12 – ISBN: 9789053630426.

S. Lehmberg, L. Ledderose, F. Wirth, H. Budelmann, and H. Kloft, “Von der Bauteil-fügung zu leichten Tragwerken: Trocken gefügte Flächenelemente aus UHPFRC,” Beton- und Stahlbetonbau, vol. 111, no. 12, pp. 806–815, 2016, doi: https://www.doi.org/10.1002/best.201600053.

F. Fingerloos, J.-D. Wörner, and K. Bergmeister, Eds., Beton-Kalender 2013: Le-bensdauer und Instandsetzung, Brandschutz. Berlin: Ernst & Sohn, 2013.

DIN EN 10025-2:2019-10, Warmgewalzte Erzeugnisse aus Baustählen_- Teil_2: Technische Lieferbedingungen für unlegierte Baustähle; Deutsche Fassung EN_10025-2:2019, Berlin.

DIN EN 14889-1:2006-11, Fasern für Beton_- Teil_1: Stahlfasern_- Begriffe, Festle-gungen und Konformität; Deutsche Fassung EN_14889-1:2006, Berlin.

S. Heinemeyer, Zum Trag- und Verformungsverhalten von Verbundträgern aus ultra-hochfestem Beton mit Verbundleisten. Dissertation, RWTH Aachen, 2011.

C. Achilleos, D. Hadjimitsis, K. Neocleous, K. Pilakoutas, P. O. Neophytou, and S. Kallis, “Proportioning of Steel Fibre Reinforced Concrete Mixes for Pavement Con-struction and Their Impact on Environment and Cost,” Sustainability, vol. 3, no. 7, pp. 965–983, 2011, doi: https://www.doi.org/10.3390/su3070965.

G. Graeff, K. Pilakoutas, K. Neocleous, and M. V. N. Peres, “Fatigue resistance and cracking mechanism of concrete pavements reinforced with recycled steel fibres re-covered from post-consumer tyres,” Engineering Structures, vol. 45, pp. 385–395, 2012, doi: https://www.doi.org/10.1016/j.engstruct.2012.06.030.

Genan, Genan - umweltfreundliches Altreifenrecycling. [Online]. Available: https://www.genan.de/ (accessed: Sep. 28 2021).

FEMM, HomePage: Finite Element Method Magnetics. [Online]. Available: https://www.femm.info/wiki/HomePage (accessed: Sep. 28 2021).

J. N. Luo and E. G. Sheu, “Physical Properties, Toxicity, and Physiological Effects of Magnets,” in Magnetic Surgery, M. Gagner, Ed., Cham: Springer International Pub-lishing, 2021, doi: https://doi.org/10.1007/978-3-030-73947-8

G. Bertram, Zum Verbund- und Querkrafttragverhalten von Spannbetonträgern aus ultra-hochfestem Beton. Zugl.: Aachen, Techn. Hochsch., Diss., 2012, 1st ed. Aachen: Eigenverl., 2012.

B. Frettlöhr, Bemessung von Bauteilen aus ultrahochfestem Faserfeinkornbeton (UHFFB). @Stuttgart, Univ., Diss., 2011. [Online]. Available: http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-71514

J. Bonzel and M. Schmidt, Verteilung und Orientierung von Stahlfasern im Beton und ihr Einfluß auf die Eigenschaften von Stahlfaserbeton. Beton 34 (1984), S. 463-470.

G. Bernier and M. Behloul, “Effet de l’orientation des fibres sur le comportement mécanique des BPR.,” 1996.

T. Stengel, Effect of Surface Roughness on the Steel Fibre Bonding in Ultra High Per-formance Concrete (UHPC), Nanotechnology in Construction 3. Springer, Berlin, Hei-delberg, 2009. 371-376, doi: https://www.doi.org/10.1007/978-3-642-00980-8_50

T. Pfyl, Tragverhalten von Stahlfaserbeton. Zugl.: Zürich, Eidgenössische Techn. Hochsch., Diss., 2002. Zürich: vdf Hochsch.-Verl. an der ETH, 2003.

I. Marković, High-Performance hybrid-fibre concrete: Development and utilisation. Zugl.: Delft, Techn. Univ., Diss., 2006. Delft: DUP Science, 2006.

T. Stengel, P. Schießl, C. Gehlen, and J. C. Walraven, Verbundverhalten und me-chanische Leistungsfähigkeit von Stahlfasern in ultrahochfestem Beton. München, Technische Universität München, Diss., 2013. München: Universitätsbibliothek der TU München, 2013.

S. Stürwald, Rissentwicklung bei kombiniert bewehrten UHPC Balken. Kassel: Kassel Univ. Press, 2012.

S. Stürwald, “Versuche zum Biegetragverhalten von UHPC mit kombinierter Beweh-rung; Forschungsbericht Fachgebiet Massivbau Fachbereich Bauingenieurwesen Universität Kassel,” 2011.

DIN EN 196-3:2017-03, Prüfverfahren für Zement_- Teil_3: Bestimmung der Erstar-rungszeiten und der Raumbeständigkeit; Deutsche Fassung EN_196-3:2016, Berlin.

Amira-Avizo 3D Software | Thermo Fisher Scientific. [Online]. Available: https://www.fei.com/software/avizo3d/%C2%A0#gsc.tab=0 (accessed: Sep. 29 2021).

Fiji. [Online]. Available: https://imagej.net/software/fiji/ (accessed: Sep. 29 2021).

J. Schnell, K. Schladitz, and F. Schuler, “Richtungsanalyse von Fasern in Betonen auf Basis der Computer-Tomographie,” BUST, vol. 105, no. 2, pp. 72–77, 2010, doi: https://doi.org/10.1002/best.200900055

S. Lehmberg, “Herstellung und Eigenschaften von dünnwandigen, trocken gefügten Bauteilen aus ultrahochfestem faserverstärkten Feinkornbeton,” Dissertation, TU Braunschweig, 2018.

SETRA, AFAC, Bétons fibrés à ultra-hautes performances, Recommandations, Re-vised edition, June 2013.

M. M. Reichel, Dünnwandige Segmentfertigteilbauweisen im Brückenbau aus gefa-sertem Ultrahochleistungsbeton (UHFB). Zugl.: Graz, Techn. Univ., Diss. Graz:, (An-hang 2) 2011.

T. Stengel, P. Schießl, „Sustainability analysisof UHPC using inventory analysis and impact assessment“, in Nachhaltiges Bauen mit ultra-hochfestem Beton: Ergebnisse des Schwerpunktprogrammes 1182. M. Schmidt, E. Fehling, and S. Fröhlich, Eds, Kassel: Kassel Univ. Press, 2014.

Lindemann, H.; Gerbers, R.; Ibrahim, S.; Dietrich F.; Dröder, K.; Raatz, A.; Kloft, H.: Development of a shotcrete 3D-printing (SC3DP) technology for Additive Manufactur-ing of reinforced freedom concrete structures. First RILEM International Conference on Concrete and Digital Fabrication – Digital Concrete 2018, Zürich: Springer, 2018.

Published

2022-02-15

How to Cite

Ledderose, L., Baghdadi, A., & Kloft, H. (2022). Magnetic Alignment of Microsteel Fibers as Strategy for Reinforcing UHPFRC. Open Conference Proceedings, 1, 99–114. https://doi.org/10.52825/ocp.v1i.79