Bending Tests on Spannglass Beams: Comparison with Post-Tensioned Concrete Structures
Publication: Journal of Structural Engineering
Volume 145, Issue 10
Abstract
The use of glass in facades and roofs poses a significant challenge for engineers because glass is a linear elastic and isotropic, but also relentlessly brittle, material. To overcome this obstacle and ensure an adequate degree of safety, the principles of concrete design may be used because concrete possesses analogous mechanical characteristics, especially with respect to its brittle failure. This has led to several research and building projects involving a variety of reinforced glass beams. This idea has encouraged research on mechanically precompressed glass beams with a special focus on Spannglass Beams—glass beams with post-tensioned reinforcement. The research presented here contributes to remedying the lack of knowledge by presenting the results of four-point bending tests on 15 two-meter-long specimens with a variety of tendon diameters and initial cable forces. The experiments showed that an increase in fracture load was possible when the glass beams were precompressed. However, the cable load needed to be limited to create safe and reliable Spannglass Beams. This limitation introduces a smaller amount of elastic energy into the system, which was proven to be problematic. Additionally, the removal of sacrificial layers from the glass web turned out to be essential. Finally, the paper draws a set of conclusions by comparing precompressed glass beams with general research on glass beams and concrete design. This will allow for novel architectural opportunities that are underpinned by profound engineering: literally invisible structures will be feasible in the future, combining the astonishing mechanical properties and transparent nature of glass.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This research project was sponsored by the German Federal Ministry for Economic Affairs and Energy (BMWi) and executed cooperatively with Thiele Glas GmbH (Wermsdorf, Germany) and KL megla GmbH (Eitorf, Germany).
References
Belis, J., C. Louter, K. Verfaillie, R. Van Impe, and D. Callewaert. 2006. “The effect of post-tensioning on the buckling behaviour of a glass t-beam.” In Proc., Int. Symp. on the Application of Architectural Glass-Engineering and Architectural Design of Glass 2006 (ISAAG), 129–136. Neubiberg, Gemany: Bundeswehr Univ. Munich.
Belis, J., D. Mocibob, A. Luible, and M. Vandebroek. 2011. “On the size and shape of initial out-of-plane curvatures in structural glass components.” Constr. Build. Mater. 25 (5): 2700–2712. https://doi.org/10.1016/j.conbuildmat.2010.12.021.
Bos, F. P., F. A. Veer, G. J. Hobbelman, and P. C. Louter. 2004. “Stainless steel reinforced and post-tensioned glass beams.” In Proc., 12th Int. Conf. of Experimental Mechanics (ICEM12). Bari, Italy: Polytechnic Univ. of Bari.
Bünemann, B. 1997. “Umbau der Lindener Volksbank in Hannover.” Glas. Architektur und Technik 2 (1): 19–24.
Cupać, J. 2017. “Post-tensioned glass beams.” Ph.D. thesis, Civil Engineering Institute, École Polytechnique Fédérale de Lausanne.
Cupać, J., and C. Louter. 2015. “Post-tensioned structural glass beams—Comparative experimental study.” Proc., Advanced Building Skins, 166–172. Graz, Austria: Institute of Building Construction, Graz Univ. of Technology.
Cupać, J., K. Martens, A. Nussbaumer, J. Belis, and C. Louter. 2017. “Experimental investigation of multi-span post-tensioned glass beams.” Glass Struct. Eng. 2 (1): 3–15. https://doi.org/10.1007/s40940-017-0038-5.
DIBt (Deutsches Institut für Bautechnik). 2015. Bauregelliste A. BRL A 02. Berlin: DIBt.
DIN (Deutsches Institut für Normung). 2011a. Eurocode 2: Design of concrete structures—Part 1-1: General rules and rules for buildings. EN 1992-1-1. Berlin: DIN.
DIN (Deutsches Institut für Normung). 2011b. Glass in building—Design and construction rules. DIN 18008. Berlin: DIN.
DIN (Deutsches Institut für Normung). 2012. Glass in building—Heat strengthened soda lime silicate glass. EN 1863. Berlin: DIN.
Engelmann, M. 2015. “Spannglass-bridge. Footbridge-design competition contribution.” In Proc., Young Engineers Workshop at IABSE Conf. Nara, Japan: International Association for Bridge and Structural Engineering.
Engelmann, M. 2017. “Spannglass beams—Glassbeams with post-tensioned reinforcement.” Ph.D. thesis, Institute of Building Construction, Faculty of Civil Engineering, Technische Universität.
Engelmann, M., and B. Weller. 2018a. “Post-tensioned glass beams for a 9 m spannglass bridge.” Struct. Eng. Int. 26 (2): 103–113. https://doi.org/10.2749/101686616X14555428759000.
Engelmann, M., and B. Weller. 2018b. “Residual load-bearing capacity of spannglass-beams: Effect of post-tensioned reinforcement.” Glass Struct. Eng. 4 (1): 11–15. https://doi.org/10.1007/s40940-018-0079-4.
Firmo, F., S. Jordão, L. C. Neves, C. A. Ferreira, and A. C. Gonçalves. 2015. “Structural behaviour of simple and pre-stressed hybrid steel-glass beams.” University of Azores. Accessed June 26, 2019. https://nbn-resolving.org/urn:nbn:de:bsz:14-qucosa-229676.
Härth, K. 2013. “Beitrag zum tragverhalten hybrider Träger aus Glas und Kunststoff.” Ph.D. thesis, Institute of Building Construction, Technische Universität Dresden.
Jordão, S., M. Pinho, J. P. Martin, A. Santiago, and L. C. Neves. 2014. “Behaviour of laminated glass beams reinforced with pre-stressed cables.” Steel Constr. 7 (3): 204–207. https://doi.org/10.1002/stco.201410027.
Kasper, R. 2005. “Tragverhalten von Glasträgern.” Ph.D. thesis, Institute of Steel Construction, Rheinisch-Westfälische Technische Hochschule Aachen.
Langosch, K. 2012. “Das tragverhalten von Glasstützen mit Mono- und Verbundquerschnitten.” Ph.D. thesis, Institute of Steel Construction, Rheinisch-Westfälische Technische Hochschule Aachen.
Laufs, W. 2000. “Ein Bemessungskonzept zur Festigkeit thermisch vorgespannter Gläser.” Ph.D. thesis, Institute of Steel Construction, Rheinisch-Westfälische Technische Hochschule Aachen.
Louter, C. 2011. “Fragile yet ductile: Structural aspects of reinforced glass beams.” Ph.D. thesis, Structural Design and Mechanics, Technische Universiteit Delft.
Louter, C., and J. Cupać. 2015. “Comparative study of post-tensioned glass beams with bonded tendons.” In Proc., Glass Performance Days (GPD), 383–386. Tampere, Finland: Glaston Finland.
Louter, C., J. Cupać, and J.-P. Lebet. 2014. “Exploratory experimental investigations on post-tensioned structural glass beams.” J. Facade Des. Eng. 2 (1–2): 3–18. https://doi.org/10.3233/FDE-130012.
Louter, C., J. H. Nielsen, and J. Belis. 2013a. “Exploratory experimental investigations on post-tensioned structural glass beams.” In Proc., Int. Conf. on Structures and Architecture (ICSA), 358–365. Braga, Portugal: Univ. of Minho.
Louter, C., A. Pérez, T. Jordan, and J.-P. Lebet. 2013b. “Post-tensioned structural glass beams—Experimental investigations.” In Proc., COST Action TU0905, Mid-term Conf. on Structural Glass, 277–284. Boca Raton, FL: CRC Press.
Louter, C., J. van Heusden, F. Veer, J. Vambersky, H. de Boer, and J. Versteegen. 2006. “Post-tensioned glass beams.” In Fracture of nano and engineering materials and structures, 597–598. Dordrecht, Netherland: Springer.
Martens, K. 2018. “Statically indeterminate reinforced glass beams.” Ph.D. thesis, Dept. of Structural Engineering, Ghent Univ. http://lib.ugent.be/catalog/rug01:002476974.
Martens, K., R. Caspeele, and J. Belis. 2015. “Development of reinforced and posttensioned glass beams: Review of experimental research.” J. Struct. Eng. 142 (5): 04015173. https://doi.org/10.1061/(ASCE)ST.1943-541X.0001453.
Martens, K., R. Caspeele, and J. Belis. 2017. “Performance of statically indeterminate reinforced glass beams—Experimental comparison with determinate systems and effect of a discontinuous glass section.” Constr. Build. Mater. 146: 251–259. https://doi.org/10.1016/j.conbuildmat.2017.03.186.
Schober, H., H. Gerber, and J. Schneider. 2004. “Ein Glashaus für die Therme in Badenweiler.” Stahlbau 73 (11): 886–892. https://doi.org/10.1002/stab.200490213.
Trost, H., H. Cordes, and B. Weller. 1984. Untersuchungen zur Vorspannung ohne Verbund.. Berlin: DAfStb.
Weller, B. 1988. Experimentelle Untersuchungen zum Biegetragverhalten von Durchlaufträgern mit Vorspannung ohne Verbund. Berlin: DAfStb.
Weller, B., and M. Engelmann. 2014a. “Deformation of spannglass beams subject to post-tensioning.” In Proc., Challenging Glass 4–Conf., on Architectural and Structural Applications of Glass (CGC4) & COST Action TU0905 Final Conf., 285–294. Lausanne, Switzerland: École Polytechnique Fédérale de Lausanne.
Weller, B., and M. Engelmann. 2014b. “Spannglasträger–Glasträger mit vorgespannter Bewehrung.” Stahlbau 83 (S1): 193–203. https://doi.org/10.1002/stab.201490059.
Weller, B., and M. Engelmann. 2015. “9 m Spannglasbrücke auf der Glasstec 2014.” Stahlbau 84 (1): 455–464. https://doi.org/10.1002/stab.201590102.
Weller, B., A. Meier, and T. Weimar. 2010. “Glass-steel beams as structural members of facades.” In Proc., Challenging Glass 2–Conf. on Architectural and Structural Applications of Glass (CGC2). Delft, Netherlands: TU Delft.
Zimmermann, J. 1988. Biegetragverhalten und Bemessung von Trägern mit Vorspannung ohne Verbund. Berlin: DAfStb.
Zschippang, S., W. Wies, B. Weller, and T. Schadow. 2006. “Glasdach Mensa und Rektorat der Technischen Universität Dresden.” Stahlbau 75 (6): 428–432. https://doi.org/10.1002/stab.200610044.
Information & Authors
Information
Published In
Copyright
©2019 American Society of Civil Engineers.
History
Received: Nov 29, 2017
Accepted: Dec 3, 2018
Published online: Jul 25, 2019
Published in print: Oct 1, 2019
Discussion open until: Dec 25, 2019
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.