PSI - Issue 64

Sizhe Wang et al. / Procedia Structural Integrity 64 (2024) 2075–2082 Author name / Structural Integrity Procedia 00 (2019) 000–000

2081

7

Strain gauges mounted on the steel plates were used to estimate the Fe-SMA prestress. Average compressive strains of the steel plates ranging from approximately -40 to -120 µm/m were observed, indicating that prestress was successfully generated and sustained across all specimens. The Fe-SMA prestress was estimated to be ranging from 154 to 249 MPa. The use of adhesively bonded Fe-SMA patches is a promising solution for crack repair and lifetime extension, wherein the activation/prestressing is a critical step. This study demonstrates the feasibility of activation of compact (as short as 100 mm) bonded Fe-SMA patches. Acknowledgements The experimental study was conducted at the Structural Research Lab at Empa, Switzerland. The authors acknowledge the National Natural Science Foundation of China (52278207), Natural Science Foundation of Shanghai (21ZR1466100), and China Scholarship Council (CSC). The authors also acknowledge the supports and sponsored materials from re-fer AG, Switzerland, Sika AG, Switzerland, and S&P AG, Switzerland. Thanks also go to Mr. André Kupferschmid and Mr. Robert Widmann for assistance in the experiments. References Abdy, A. I., Hashemi, M. J. & Al-Mahaidi, R. 2018. Fatigue life improvement of steel structures using self-prestressing CFRP/SMA hybrid composite patches. Engineering Structures, 174, 358-372. Chen, T., Li, L., Zhang, N., Song, X. & Hidekuma, Y. 2018. Fatigue performance test on inclined central cracked steel plates repaired with CFRP strand sheets. Thin-Walled Structures, 130, 414-423. Cladera, A., Weber, B., Leinenbach, C., Czaderski, C., Shahverdi, M. & Motavalli, M. 2014. Iron-based shape memory alloys for civil engineering structures: An overview. Construction and Building Materials, 63, 281-293. Gu, X.-L., Chen, Z.-Y., Yu, Q.-Q. & Ghafoori, E. 2021. Stress recovery behavior of an Fe-Mn-Si shape memory alloy. Engineering Structures, 243, 112710. Izadi, M., Motavalli, M. & Ghafoori, E. 2019. Iron-based shape memory alloy (Fe-SMA) for fatigue strengthening of cracked steel bridge connections. Construction and Building Materials, 227, 17. Izadi, M. R., Ghafoori, E., Motavalli, M. & Maalek, S. 2018. Iron-based shape memory alloy for the fatigue strengthening of cracked steel plates: Effects of re-activations and loading frequencies. Engineering Structures, 176, 953-967. Li, L., Chatzi, E., Czaderski, C. & Ghafoori, E. 2023a. Influence of activation temperature and prestress on behavior of Fe-SMA bonded joints. Construction and Building Materials, 409, 134070. Li, L., Wang, S., Chatzi, E., Motavalli, M. & Ghafoori, E. 2024. Analysis and design recommendations for structures strengthened by prestressed bonded Fe-SMA. Engineering Structures, 303, 117513. Li, L., Wang, W., Chatzi, E. & Ghafoori, E. 2023b. Experimental investigation on debonding behavior of Fe-SMA-to-steel joints. Construction and Building Materials, 364, 129857. Li, L. Z., Chen, T., Gu, X. L. & Ghafoori, E. 2020. Heat Activated SMA-CFRP Composites for Fatigue Strengthening of Cracked Steel Plates. Journal of Composites for Construction, 24. Liu, H., Al-Mahaidi, R. & Zhao, X.-L. 2009. Experimental study of fatigue crack growth behaviour in adhesively reinforced steel structures. Composite Structures, 90, 12-20. Pichler, N., Wang, W., Motavalli, M., Taras, A. & Ghafoori, E. 2024. Mode I fracture analysis of Fe-SMA bonded double cantilever beam considering nonlinear behavior of the adherends. Engineering Fracture Mechanics, 295, 109789. Pichler, N., Wang, W., Poulis, J. A. & Ghafoori, E. 2023. Surface preparations and durability of iron-based shape memory alloy adhesively-bonded joints. International Journal of Adhesion and Adhesives, 103439. Wang, S., Li, L., Su, Q., Jiang, X. & Ghafoori, E. 2023a. Strengthening of steel beams with adhesively bonded memory-steel strips. Thin-Walled Structures, 189, 110901. Wang, S., Su, Q., Jiang, X., Li, L., Motavalli, M. & Ghafoori, E. 2024a. Self-prestressing bonded patches using Fe-SMA and CFRP for lifetime extension of fatigue-cracked steel details. Construction and Building Materials (under review). Wang, S., Su, Q., Jiang, X., Michels, J. & Ghafoori, E. 2024b. Fully bonded iron-based shape memory alloy for retrofitting large-scale bridge girders: Thermal and mechanical behavior. Structures, 65, 106710. Wang, S., Su, Q., Jiang, X., Motavalli, M. & Ghafoori, E. 2023b. Development of repair solution for fatigue cracks using self-prestressing Fe SMA/CFRP bonded patches. 11th International Conference on Fiber-Reinforced Polymer (FRP) Composites in Civil Engineering (CICE 2023). Rio de Janeiro, Brazil. Wang, W., Li, L., Hosseini, A. & Ghafoori, E. 2021. Novel fatigue strengthening solution for metallic structures using adhesively bonded Fe-SMA strips: A proof of concept study. International Journal of Fatigue, 148, 106237. Wang, W., Zhou, W., Ma, Y. E., Motavalli, M. & Ghafoori, E. 2024c. Complete fatigue crack arrest in metallic structures using bonded prestressed iron-based shape memory alloy repairs. International Journal of Fatigue, 180, 108104.