Abstract
This paper presents some of the initial results from an ongoing research project which concerns a new NSMR strengthening method, expected to provide high ductility and strengthening effect as well as increased response consistency. A prestress of 1100 MPa activation was applied to the ductile NSMR system and compared to a reference beam. Ductility in this system is provided by a response controlling anchorage system, which interacts with the adhesively bonded NSMR. The proposed adhesive has a low E-modulus which is expected to reduce stress concentration issues of adhesively bonded joints when compared to stiffer epoxy adhesives are used, where IC-debonding seems to be the dominating failure mode. A beam deflection increase of approximately 105% has been observed when using the low E-modulus adhesive compared to the the epoxy adhesive. Change in the failure modes were furthermore observed, where the brittle de-bonding failure modes were mitigated thus extending the yielding regime with approximately 150%.
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Acknowledgements
A sincere gratitude is addressed to S&P Denmark for supporting the ongoing research. Also a great thank you to Jorcks foundation for their acknowledgement and funding. Thank you to Perstrup Beton industri A/S. Furthermore the contributions from former students Frederik Alexander Meinzer Vind, Frederik Jensen, Nathalie Lückstädt Nielsen, Frits Eið, Frederik Munck, Matias Brix Mikkelsen, Klavs Foged Skovby and Nicolaj Jacob Birkebæk Thomsen is greatly appreciated. The last author acknowledge the grant SFRH/BSAB/150266/2019 provided by FCT financed by European Social Fund and by national funds through the FCT/MCTES, supporting his stay at DTU.
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Schmidt, J.W., Christensen, C.O., Goltermann, P., Sena-Cruz, J. (2022). Activated CFRP NSMR Ductile Strengthening System. In: Sena-Cruz, J., Correia, L., Azenha, M. (eds) Proceedings of the 3rd RILEM Spring Convention and Conference (RSCC 2020). RSCC 2020. RILEM Bookseries, vol 34. Springer, Cham. https://doi.org/10.1007/978-3-030-76465-4_31
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DOI: https://doi.org/10.1007/978-3-030-76465-4_31
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