Experimental study on shear strengthening of steel beams using CFRP strips

Document Type : Original Article

Authors

1 Assistant Professor of Structural Engineering, Department of Civil Engineering, Faculty of Engineering, Zahedan Branch, Islamic Azad University, Zahedan, Iran

2 Department of Civil Engineering, Zahedan Branch, Zahedan, Iran

Abstract

Steel structures are one of the most used type of structures. Some of the steel structures may need to be strengthened due to different reasons. There are different methods for strengthening of this kind of structures. In recent years, strengthening of steel structures using Fiber Reinforced Polymers (FRP) has been most interested. This study investigates the shear strengthening of steel beams using one and both sides strengthening of the web by different angles of Carbon Fiber Reinforced Polymers (CFRP) strips. Five specimens were investigated in laboratory experimentally. The test method was four-point bending approach. The load was applied on a connector loading beam by a hydraulic jack, then the load was applied on the main beam through two equal point loads. The beams had two simple supports at the both ends. The loading type was the static gradual loading type. The dimensions of the beams were chosen in the way that beams behave most in shear. This means that beams fail first due to shear stress. One beam was not strengthened, and two beams were strengthened using vertical strips on one or both sides of the web, and two remained beams were upgraded using diagonal strips. Results of this research indicates efficiency of CFRP strips for increasing load-bearing capacity of the beams. Strengthening using diagonal strips on both sides of the web demonstrated the most increment in load-bearing capacity.

Keywords

Main Subjects

References

[1] Schnerch, D., Stanford, K., Sumner, E., Rizkalla, S. (2005). Bond behavior of CFRP strengthened steel bridges and structures. International Symposium on Bond Behaviour of FRP in Structures (BBFS 2005). International Institute for FRP in Construction.
[2] Linghoff, D., Al-Emrani, M. (2009). Performance of steel beams strengthened with CFRP laminate– Part 2: FE analyses. Composites: Part B: Engineering, 41(7), 516-522.

[3] Linghoff, D., Haghani, R., Al-Emrani, M. (2009). Carbon-fibre composites for strengthening steel structures. Thin-Walled Structures, 47(10), 1048-1058.

[4] Linghoff, D., Al-Emrani, M., Kliger, R. (2010). Performance of steel beams strengthened with CFRP laminate– Part 1: Laboratory tests. Composites Part B: Engineering, 41(7), 509-515.
[5] Salama, T., Abd-El-Meguid, A. (2010). Strengthening Steel Bridge Girders Using CFRP. UTCA Report Number 06217.
[6] Narmashiri, K., Jumaat, M.Z. (2011). Reinforced steel I-beams: A comparison between 2D and 3D simulation. Simulation Modeling Practice and Theory, 19, 564-585.
[7] Narmashiri, K., Ramli Sulong, N.H., Jumaat, M.Z. (2011). Flexural strengthening of steel I-beams by using CFRP strips. International Journal of the Physical Science, 6(7), 1620-1627.
[8] Narmashiri, K., Ramli Sulong, N.H., Jumaat, M.Z. (2012). Failure analysis and structural behavior of CFRP strengthened steel I-beams. Construction and Building Materials, 30, 1-9.
[9] Narmashiri, K., Jumaat, M.Z., Ramli Sulong, N.H. (2011). Local stiffening of steel I-beams by using CFRP materials. Advanced Materials Research, 163-167, 3833-3843.
[10] Patnaik, A., Bauer, C.L., Srivatsan, T.S. (2008). The extrinsic influence of carbon fibre reinforced plastic laminates to strengthen steel structures. Sadhana, 33, 261–272.
[11] Narmashiri, K., Jumaat, M.Z., Ramli Sulong, N.H. (2010). Shear strengthening of steel I-beams by using CFRP strips. Scientific Research and Essays, 5(6), 2155-2168.
[12] Azizi, S., Narmashiri, K., Mehmandoost Kotlar, H. (In Press). Shear strengthening of plate girders using carbon-fibre-reinforced polymer composites. Proceeding of the Institution of Civil Engineers - Construction Materials, http://dx.doi.org/10.1680/jcoma.16.00078.

Files

History

  • Receive Date: 16 June 2018
  • Revise Date: 14 January 2019
  • Accept Date: 15 January 2019

Share

How to cite

Statistics