Adhesively Bonded Joints

International Collaborative Project

Strengthening of existing steel structures using prestressed members is an economical and simple method for increasing their lifespan, which can help to increase the sustainability of structures. Iron-based shape memory alloy (Fe-SMA) has a great potential in this regard, since the prestress can be easily applied by heating the prestrained Fe-SMA followed by a cooling process (the so called activation process) [1]. Examples of bridge retrofitting [2] and fatigue crack repair [3] with Fe-SMA have shown the great potential of SMAs for structural repair. However, there are still open questions regarding bonded Fe-SMA strengthening solutions, such as ensuring a reliable bonding interface and effectively apply and transfer the prestress to the parent structure. Such an adhesively bonded joints are also often used for strengthening of steel structures using carbon fibre reinforced polymers (CFRP) materials. There is a need for further studies in particular on finite element simulations of such joints.

Requirements:

The work is in collaboration with the international partners. The supervision of the work will be primary conducted remotely and online.
Given the international nature of the project, the language of the work (including presentations and report) will be in English.
A master thesis (Masterarbeit) is preferred for this topic.

References

[1] E. Ghafoori, E Hosseini, C Leinenbach, J Michels, M Motavalli, “Fatigue behavior of a Fe-Mn-Si shape memory alloy used for prestressed strengthening” Materials & Design, 133, 349-362, 2017.
[2] J. Vůjtěch, P. Ryjáček, J. Campos Matos, and E. Ghafoori, “Iron-Based shape memory alloy for strengthening of 113-Year bridge,” Engineering Structures, vol. 248, p. 113231, 2021.
[3] W. Wang, L. Li, A. Hosseini, and E. Ghafoori, “Novel fatigue strengthening solution for metallic structures using adhesively bonded Fe-SMA strips: A proof of concept study,” International Journal of Fatigue, vol. 148, p. 106237, 2021.