PSI - Issue 28

Jamal A. Abdalla et al. / Procedia Structural Integrity 28 (2020) 2312–2319 Author name / Structural Integrity Procedia 00 (2019) 000–000

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Comparing the failure modes of different strengthened beams as shown in Figure 6, it can be observed that all beams failed in the same manner, which was yielding in steel first then followed by FRP Delamination. Except the beam with CFRP+AA were FRP rupture first then followed by delamination (concrete cover separation), which indicates that the maximum capacity of CFRP laminates had been achieved and the strengthening system was fully utilized. 4. Conclusions It can be concluded from this study that:  The hybrid coupon laminates that combined AA with CFRP and AA with GSM, showed a ductile behavior with elongation enhancement compared to the CFRP and GSM laminates alone.  The experimental results showed that beams strengthened with the proposed hybrid system of AA, CFRP and GSM provided improved flexural capacity and ductility values.  The flexural capacity of the strengthened beams increased by 27% to 38% over the control beam. And the ductility of beams strengthened with SMH+AA yielded the highest increase by 98.5% compared to control beam.  All strengthened beams failed in the same manner which was yielding in steel then FRP delamination, except for CFRP+AA that failed by FRP ruptured first then followed by delamination.  The results are promising and encouraging for improving the flexural performance of RC beams using the proposed hybrid strengthening materials. Acknowledgements The support for the research presented in this paper had been partially provided by Riad Sadek Endowed Chair in Civil Engineering at the American University of Sharjah. The support is gratefully appreciated and acknowledged. The views and conclusions, expressed or implied, in this study are those of the authors and should not be interpreted as those of the donor or the institution. References Abdalla, J.A., Abu-Obeidah, A.S., Hawileh, R.A., Rasheed, H.A. 2016. Shear strengthening of reinforced concrete beams using externally-bonded aluminum alloy plates: An experimental study, 128, 24-37. Abdalla, J.A., Hraib, F.H., Hawileh, R.A., Mirghani, A.M., 2017. Experimental investigation of bond-slip behavior of aluminum plates adhesively bonded to concrete', Journal of Adhesion Science and Technology, 31(1), 82-99. Abdalla, J.A., Hawileh, R.A. Nawaz, W., Mohammed, A. Reinforced concrete beams externally strengthened in flexure using hybrid systems," 2018 Advances in Science and Engineering Technology International Conferences (ASET), Abu Dhabi, 2018, pp. 1-5, doi: 10.1109/ICASET.2018.8376864. Abuodeh, O., Abdalla, J.A., Hawileh, R.A., 2019. The flexural behavior of bolting and bonding Aluminum Alloy plates to RC beams. The Third International Conference on Structural Integrity. Procedia Structural Integrity, 17, 395-402. Abu-Obeidah, A.S., Abdalla, J.A., Hawileh, R.A., 2019. Shear strengthening of deficient concrete beams with marine grade aluminium alloy plates. Advances in concrete construction 7 (4), 249-262. ACI Committee 440, Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures. Farmington Hills, Michigan (USA): American Concrete Institute, 2017. Al-Nuaimi, N., Sohail, M.G., Hawileh, R.A., Abdalla, J.A., Douier, K. (2020). Durability of Reinforced Concrete Beams Strengthened by Galvanized Steel Mesh-Epoxy Systems under Harsh Environmental Conditions. Composite Structures, 112547. Ali, A., Abdalla, J.A., Hawileh, R.A., Galal, K., 2014. CFRP Mechanical Anchorage for Externally Strengthened RC Beams under Flexure. Physics Procedia, 55, Supplement C, 10-16. Akbarzadeh, H., Maghsoudi, A., 2010. Experimental and analytical investigation of reinforced high strength concrete continuous beams strengthened with fiber reinforced polymer, Materials. Design, 31(3), 1130-1147. Ashour, A.F., El-Refaie, S.A., Garrity, S.W., 2004. Flexural strengthening of RC continuous beams using CFRP laminates, Cem. Concr. Compos., 26(7), 765–775. ASTM D3039/D 3039M-08. Standard Test Method for Tensile Properties of Polymer- Matrix Composite Materials, 2016. Bahn, B. Y., and Harichandran, R. S., 2008. Flexural behavior of reinforced concrete beams strengthened with CFRP sheets and epoxy mortar. Journal of Composites for Construction, 12(4), 387–395. Bakis, C. E., Bank, L. C., Brown, V. L., Cosenza, E., Davalos, J. F., Lesko, J. J., Machida, A., Rizkalla, S. H., and Triantafillou, T. C., 2002. Fiber reinforced polymer composites for construction - State-of-the-art review. Journal of Composites for Construction, 6(2), 73–87.