Glass to build with

Title of the research project

GLASS & CO - Enhancing the effective strength of structural GLASS with functional COatings

Scientific area 

Civil Engineering, Architecture, Materials science

Project coordinator

Mauro Corrado

Abstract

The project developed new and innovative transparent functional coatings, i.e. transparent polimeric films, to enhance the mechanical properties of glass and make it strong enough to be used to make load-carrying elements for buildings.

Description of the research project 

Glass is an increasingly used material in building industry but innovative technologies are needed for load-carrying building elements and to allow innovative architectural solutions.

GLASS & CO  focused on two specific issues that limit the exploitable tensile and compressive strengths for annealed glass, thus limiting its use in load-carrying structural members: the stress corrosion and the stress concentration. 

The stress corrosion is the phenomenon of decrease of the tensile strength over time, which is due to the combined effect of weathering and applied loads.

The stress concentration herein considered, is that taking place in a glass plate when contact pressures are applied along the edges and can determine the appearance of splitting cracks for compressive stresses.

A technological solution was provided by means of the development of functional polymeric coatings:

  • Highly hydrophobic coatings, optimized to guarantee also good adhesion with the glass substrate, appear as an effective solution to the stress corrosion.
  • Thick coatings having tailored mechanical properties may reduce the stress concentration by accommodating the roughness of the edges and redistributing the pressures.

The development of such new materials was supported by experimental tests to evidence the aspects involved in the problems, numerical simulations to identify the theoretical optimal solutions, and testing of the performance, both on small-scale specimens and on real structural components. A highly interdisciplinary research that required competences from material science, numerical modelling and structural design.

Impact on society 

The developed coatings will contribute to improve the reliability of structural glass members, thus promoting the use of glass for demanding structural applications and reducing its consumption in the building industry. Such functional coatings will might be applied systematically to new elements, as well as they will be available also for in-situ applications, giving the possibility to strengthen existing structures. This would be particularly interesting for architectural heritage preservation.

Furthermore, the adopted technology has unquestionable advantages with respect to conventional strengthening techniques since it is less energy consuming than the thermal temper and cheaper than the chemical temper.

Research results

The developed polymeric coatings make glass a much more solid and resistant construction material, preventing the problem of stress corrosion and reducing the sensitivity of glass to stress along the edges. The technology has undeniable advantages compared to conventional techniques: it consumes less energy that thermal tempering and it is cheaper than chemical tempering. The tensile strength of coated glass increases by 90%. Moreover, the project has explored the use of additive manufacturing technology to couple polymeric materials with glass, thus opening new possibilities for the development of composite glass-polymers materials.

Among the main scientific results and impacts we highlight:

  • 9 scientific publications and  5 project presentations to conferences
  • New collaborations with the  School for Advanced Studies di Lucca and the  Technische Universität Darmstadt (Germany).
  • New contacts with 2 Italian industries/industrial sites: SpA and AGC Glass Europe
  • Participation to the EU project NEWFRAC funded under the call Marie Sklodowska-Curie Innovative Training Network 2018.

Short CV of project coordinator 

Mauro Corrado received his Master's Degree in Civil Engineering in 2004 and his Ph.D. in Structural Engineering in 2008 from Politecnico di Torino. After a post-Doctoral Fellowship at Politecnico di Torino from 2008 to 2011 he became Assistant Professor of Structural Mechanics at DISEG - Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino. From 2014 to 2016 he was a Marie Curie Fellow in the Computational Solid Mechanics Laboratory of EPFL, Switzerland. He was appointed visiting Professor in the IMT School for Advanced Studies Lucca on February 2014 and April 2017. He is member of the editorial board of the journal “Frattura ed Integrità Strutturale”. He served as peer-reviewer for the Italian Ministry of Education, University and Research, and the Czech Fulbright-Masaryk Commission.

Working group@Polito

Roberta Maria Bongiovanni, Full Professor , DISAT - Department of Applied Science and Technology

Simonetta Lucia Pagliolico, Assistant Professor, DISAT

Sara Dalle Vacche, Postdoctoral fellow, DISAT

Gregorio Mariggiò, Postdoctoral fellow, DISEG

Partenariato

Academic Partner 

Glass and Transparency Research Group, Delft University of Technology, The Netherlands

Non-academic Partner 

Cromology Italia S.p.A., Italy

  • Budget: 150.000
  • Start date: 15/09/2017
  • End date: 14/09/2019