Rehabilitation of Compression Steel Members Using FRP Pipes Filled with Non-Expansive and Expansive Light-Weight Concrete

Abstract

This paper presents the experimental and analytical evaluation of the feasibility of a proposed fiber reinforced polymer (FRP) retrofit method to strengthen corroded steel columns. This method consists of two steps: (1) wrapping the corroded steel column with an FRP jacket, and (2) filling the jacket with expansive light-weight concrete. Seven steel columns were tested in the laboratory including five strengthened columns with the proposed technique. The first two were used as control units where one was a virgin shape and the second was notched in the center zone to simulate the loss of section due to corrosion. The remaining five were all notched, and confined with FRP composite pipes within the simulated corroded zone and subsequently filled with light-weight concrete. All specimens were axially loaded to failure while strain and displacement readings were measured to demonstrate the feasibility of this repair concept. Test results show that the proposed FRP retrofit method for steel columns can be successfully applied. Furthermore, an analytical model was developed that can predict the load capacity of the FRP retrofitted steel column.

Keywords

confinement expansive concrete glass fiber reinforced polymer (GFRP)FRP confined concrete light-weight concrete steel column strengthening

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References

Chen

W.F.

and Lui

E.M.

(1987). Structural Stability: Theory and Implementation, New York: Elsevier, Chapter 2: “Columns”, pp. 490.

CIRIA (2004). Strengthening Metallic Structures using Externally-Bonded Fibre-Reinforced-Polymers-C595, ISBN 086017-595-2, London, CIRIA.

El-Badry

(editor) (1996). Advanced Composite Materials in Bridges and Structures, Proceedings ACMBS-II, Montreal, Canada, pp. 1027.

Euler

(1744). De Curvis Elasticis. Lausanne and Geneva, pp. 267–268. (The Euler formula was derived in a later paper: Sur le Force de Colonnes, Memoires de l'Academie Royale des Sciences et Belles Lettres, Vol. 13, Berlin, 1759)

GangaRao

H.V.S.

Thippeswamy

H.K.

Shekar

and Craigo

(1999). “Development of glass fiber reinforced polymer composite bridge deck”, SAMPE Journal, Vol. 35, No. 4, pp. 12–24.

Hollaway

L.C.

(2002), “The development and future of advanced polymer composites in the civil infrastructure”, in Proceedings of the First International Conference ACIC, Thomas Telford, UK, April, pp. 3–21.

Liu

Nanni

and Silva

P.F.

(2003). “Local bond-slip relationship between smooth steel bar and FRP confined expansive light-weight concrete”, ASCE Journal of Materials, in Civil Engineering, in print.

Nanni

and Dolan

C.W.

Eds. (1993). FRP Reinforcement for Concrete Structures, Proc., ACI SP-138, American Concrete Institute, Detroit, MI, pp. 977.

Oehlers

D.J.

and Bradford

M.A.

(1999). Elementary Behavior of Composite Steel & Concrete Structural Members, Biddles Ltd, Chapter 8: “Slender column”, pp. 259.

10.

Timoshenko

(1908). Buckling of Bars of Variable Cross-section, Bull. Polytech. Inst., Kiev.

11.

American Concrete Institute (ACI) Committee 318 (2002). Building Code Requirements for Structural Concrete (ACI 318–02) and Commentary (ACI 318R-02), Chapter 10: “Flexural and axial loads”.

12.

American Institute of Steel Construction, Inc. (AISC) (1998). Manual of Steel Construction, Load & Resistance Factor Design, second edition, Chapter C: “Frames and other structures” of Part 6 “Specifications and codes”.