Skip to main content
SpringerLink
Log in

FRP confinement of wall-like reinforced concrete columns

  • Original Article
  • Published:
Materials and Structures Aims and scope Submit manuscript

Abstract

The paper investigates FRP confinement of wall-like reinforced concrete columns in a systematic way, by examining a number of parameters not addressed before: the effectiveness of different types of anchors, the role of different cross section aspect ratios (3 and 4), the number of layers, local strengthening at the corners and the reduction of aspect ratio by cross section enlargement. These parameters are combined in an analytical model for the ultimate load in concentrically loaded columns, which is found in good agreement with test results. It is concluded that: properly dimensioned (heavy) anchors nearly double the confining effectiveness of FRP; the use of additional FRP layers near the edges of the cross section increases the confining effectiveness of the jacket by approximately 50 %; and shape enlargement of the cross section with mortar is practically as effective as the use of heavy anchors.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

Abbreviations

A c :

Area of concrete

A e :

Effectively confined area

A g :

Gross section area

A s :

Area of longitudinal steel reinforcement

A un :

Unconfined area

D :

Diameter of circular column

D* :

Diameter of equivalent circular column

P :

Total load

P c :

Load carried by concrete

P s :

Load carried by longitudinal steel

R :

Radius at corners of cross section

a f :

Confinement effectiveness factor

b :

Small dimension of cross section

h :

Large dimension of cross section

f c :

Compressive strength of unconfined concrete

f cc :

Compressive strength of confined concrete

f f :

Unidirectional tensile strength of jacket

f f,h :

Tensile strength of jacket in the hoop direction

f s :

Compressive stress of steel reinforcement

k R :

Factor to account for the effect of radius

k 1 :

Reduction factor

n :

Number of anchors at cross section

s a :

Vertical spacing of anchors

t f :

Thickness of FRP jacket

References

  1. Ceroni F, Pecce M (2010) Evaluation of bond strength in concrete elements externally reinforced with CFRP sheets and anchoring devices. J Compos Constr 14(5):521–530

    Article  Google Scholar 

  2. DAfStb (2012). On the strengthening of concrete parts with adhesively bonded reinforcement, German Committee for Reinforced Concrete

  3. Ekenel M, Rizzo A, Myers JJ, Nanni A (2006) Flexural fatigue behavior of reinforced concrete beams strengthened with FRP fabric and precured laminate systems. J Compos Constr 10(5):433–442

    Article  Google Scholar 

  4. EN 1015-11 (1993) Methods of test for mortar for masonry: part 11: determination of flexural and compressive strength of hardened mortar. European Committee for Standardization, Brussels

  5. EN 2561 (1995) Carbon fibre reinforced plastics: unidirectional laminates—tensile test parallel to the fibre direction. European Committee for Standardization, Brussels

  6. Eshwar N, Nanni A, Ibell TJ (2008) Performance of two anchor systems of externally bonded fiber-reinforced polymer laminates. ACI Mater J 105(1):72–80

    Google Scholar 

  7. Harajli M, Hantouche E, Soudki K (2006) Stress-strain model for fiber-reinforced polymer jacketed concrete columns. ACI Struct J 103(5):672–682

    Google Scholar 

  8. Hosny A, Shahin H, Abdelrahman A, El-Afandy T (2001) Strengthening of rectangular RC columns using CFRP. In: Burgoyne C (ed) Proceedings of 5th international conference on fibre-reinforced plastics for reinforced concrete structures, pp 773–782

  9. Huaco GD, Jirsa JO, Bayrak O (2011) Quality control test for carbon fiber reinforced polymer (CFRP) anchors for rehabilitation. In: 10th international symposium on fiber-reinforced polymer reinforcement for concrete structures, American Concrete Institute, SP-275, vol 40, pp 1–18

  10. Ilki A, Peker O, Karamuk E, Demir C, Kumbasar N (2008) FRP retrofit of low and medium strength circular and rectangular reinforced concrete columns. J Mater Civ Eng 20(2):169–188

    Article  Google Scholar 

  11. Jinno Y, Tsukagoshi H, Yabe Y (2001) RC beams with slabs strengthened by CF sheets and bundles of CF strands. In: Burgoyne CJ (ed) 5th international conference on fibre-reinforced plastics for reinforced concrete structures, Thomas Telford, pp 981–988

  12. Karantzikis M, Papanicolaou CG, Antonopoulos C, Triantafillou TC (2005) Experimental investigation of non-conventional confinement for concrete using FRP. J Comp Constr 9(6):480–487

    Article  Google Scholar 

  13. Kim SJ, Smith ST (2010) Pullout strength models for FRP anchors in uncracked concrete. J Compos Constr 14(4):406–414

    Article  Google Scholar 

  14. Kim Y, Quinn KT, Satrom CN, Ghannoum WM, Jirsa JO (2011a) Shear strengthening RC T-beams using CFRP laminates and anchors. In: 10th international symposium on fiber-reinforced polymer reinforcement for concrete structures, American Concrete Institute, SP-275, vol 36, pp 1–17

  15. Kim I, Jirsa JO, Bayrak O (2011) Use of carbon fiber-reinforced polymer anchors to repair and strengthen lap splices of reinforced concrete columns. ACI Struct J 108(5):630–640

    Google Scholar 

  16. Kobayashi K, Fujii S, Yabe Y, Tsukagoshi H, Sugiyama T (2001) Advanced wrapping system with CF-anchor—stress transfer mechanism of CF-anchor.” In: Burgoyne CJ (ed) 5th international conference on fibre-reinforced plastics for reinforced concrete structures. Thomas Telford, London, pp 379–388

  17. Koutas L, Triantafillou TC (2013) Use of anchors in shear strengthening of reinforced concrete T-beams with FRP. J Compos Constr 17(1):101–107

    Article  Google Scholar 

  18. Lam L, Teng JG (2003) Design-oriented stress-strain model for FRP-confined concrete in rectangular columns. J Reinf Plast Compos 22(13):1149–1186

    Article  Google Scholar 

  19. Lam L, Teng JG (2003) Design-oriented stress-strain model for FRP-confined concrete. Constr Build Mater 17:471–489

    Article  Google Scholar 

  20. Nagai H, Kanakubo T, Jinno Y, Matsuzaki Y, Morita S (1999) Study on structural performance of reinforced concrete columns with waist-high walls strengthened by carbon fiber reinforced plastic sheets. In: Dolan CW, Rizkalla SH, Nanni A (eds) 4th international symposium on fiber reinforced polymer reinforcement for reinforced concrete structures, ACI SP-188, pp 255–267

  21. Niemitz CW, James R, Brena SF (2010) Experimental behavior of carbon fiber-reinforced polymer (CFRP) sheets attached to concrete surfaces using CFRP anchors. J Compos Constr 14(2):185–194

    Article  Google Scholar 

  22. Orton S, Jirsa JO, Bayrak O (2008) Design considerations of carbon fiber anchors. ASCE J Compos Constr 12(6):608–616

    Article  Google Scholar 

  23. Ozbakkaloglu T, Saatcioglu M (2009) Tensile behavior of FRP anchors in concrete. J Compos Constr 13(2):82–92

    Article  Google Scholar 

  24. Prota A, Manfredi G, Cosenza E (2006) Ultimate behaviour of axially loaded RC wall-like columns confined with GFRP. Compos B 37:670–678

    Article  Google Scholar 

  25. Smith ST, Hu S, Kim SJ, Seracino R (2011) Strength and deflection enhancement of RC slabs with anchored FRP strengthening. In: 10th international symposium on fiber-reinforced polymer reinforcement for concrete structures, American Concrete Institute, SP-275, vol 68, pp 1–14

  26. Tan KH (2002) Strength enhancement of rectangular reinforced concrete columns using fiber-reinforced polymer. J Compos Constr 6(3):175–183

    Article  Google Scholar 

  27. Tanwongsval S, Maalej M, Paramasivam P (2003) Strengthening of RC wall-like columns with FRP under sustained loading. Mater Struct 36:282–290

    Article  Google Scholar 

  28. Triantafillou TC, Papanicolaou CG, Zisimopoulos P, Laourdekis T (2006) Concrete confinement with textile reinforced mortar (TRM) jackets. ACI Struct J 103(1):28–37

    Google Scholar 

  29. Vrettos I, Kefala E, Triantafillou TC (2013) Innovative flexural strengthening of RC columns using carbon fiber anchors. ACI Struct J 110(1):63–70

    Google Scholar 

Download references

Acknowledgments

The authors wish to thank the students D. Kakavas, M. Karahaliou, M. Karydi, G. Kontopoulos and G. Skarakis, for their assistance in the experimental program. The research was funded by Fyfe Europe S.A. Special thanks go to M. Karantzikis and C. Kolyvas of Fyfe Europe S.A. for their input in the design of the experimental program.

Author information

Authors and Affiliations

  1. Department of Civil Engineering, University of Patras, 26500, Patras, Greece

    T. C. Triantafillou, E. Choutopoulou, E. Fotaki, M. Skorda, M. Stathopoulou & K. Karlos

Authors
  1. T. C. Triantafillou
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. E. Choutopoulou
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. E. Fotaki
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. M. Skorda
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. M. Stathopoulou
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. K. Karlos
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to T. C. Triantafillou.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Triantafillou, T.C., Choutopoulou, E., Fotaki, E. et al. FRP confinement of wall-like reinforced concrete columns. Mater Struct 49, 651–664 (2016). https://doi.org/10.1617/s11527-015-0526-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1617/s11527-015-0526-5

Keywords

Search

Navigation