Research Articles | Challenge Journal of Concrete Research Letters

Experimental Study on The Behavior of Slender Rectangular Columns Under Eccentric Loading

Emad El-Sayed Etman
Emad El-Sayed Etman * Department of Structural Engineering, Faculty of Engineering Tanta University, Egypt
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Abstract


This paper includes an extensive experimental program consisted of twenty seven specimens to investigate the behavior of reinforced concrete, RC, slender columns with rectangular sections under the effect of eccentric loads. The program contains three groups each has 9 specimens. The first group (A) is considered as a control group tested without strengthening and the second group (B) is strengthened using near surface mounted (NSM) longitudinal steel bars while the third group (C) is strengthened using NSM longitudinal steel bars partially wrapped with one ply of carbon fibers reinforced polymers (CFRP) sheets was used. In addition to the strengthening schemes, the test parameters included the investigation on the change in the ratio of the internal longitudinal steel bars as well as the stirrups’ volumetric ratio. All specimens are tested eccentric loading with eccentricity-to-section height e/h equals 0.25. The research revealed that the strength gain in specimens in group (C) is higher than in group (B).

Keywords


strengthening; FRP; RC slender columns; eccentric loads; confinement

References


Chai, Y.H.; Priestly, M.J.N. and Seible, F., Seismic Retrofit of Circular Bridge Columns for Enhanced Flexural Performance. Struct. J., 1991. 88(5): p.572-584.

Priestly, M.J.N.; Seible, F.; Xiao, Y. and Verma, R., Steel Jacket Retrofitting of Reinforced Concrete Bridge Columns for Enhanced Shear Strength-Part 1: Theoretic Consideration and Test Design. ACI Struct. J., 1994a. 91(4):p.394-405.

Priestly, M.J.N.; Seible, F.; Xiao, Y. and Verma, R., Steel Jacket Retrofitting of Reinforced Concrete Bridge Columns for Enhanced Shear Strength-Part 2: Test Results and Comparison with Theory. ACI Struct. J., 1994b. 91(5):p.537-551.

Etman, E.E. and A. Khalil, A., Effect Of Corner Radius On The Behavior Of Strengthened R.C. Columns With Different Heights. AICSGES, Fifth Alexandria International Conference on Structural and Geotechnical Engineering, Alexandria, 2003, Volume II, pp RC 345-360. Egypt.

Saadatmanesh, H.; Ehsani, M.R. and LI, M.W., Strength and ductility of concrete columns externally reinforced with fiber composite straps. ACI Struct. J., 1994. 91(4):p.443–447.

Pessiki, S.; Harries, K.; Kestner, J.; Sause, R. and Ricles, J., Axial behavior of reinforced concrete columns confined with FRP jackets. J. Compos. Constr., 2001. 5(4):p.237–245.

Wang, Y.C. and Restrepo, J.I., Investigation of concentrically loaded reinforced concrete columns confined with glass fiber reinforced polymer jackets. ACI Struct. J., 2001. 98(3):p.377–385.

Chaallal, O.; Shahawy, M. and Hassan, M., Performance of axially loaded short rectangular columns strengthened with carbon fiber reinforced polymer wrapping. J. Compos. Constr., 2003. 7(3):p.200–208.

Etman, E.E., Efficiency of Strengthening RC Columns, With Different Slenderness Ratios, Using “CFRP” Wraps. 27th conference on our world in concrete & structures, 29-30 August 2002, Singapore.

Lin, H.J. Liao, C.I., Compressive strength of reinforced concrete column confined by composite material. J. Compos. Constr., 2004. 65(2):p.239–250.

Berthet, J.F.; Ferrier, E. and Hamelin, P., Compressive behavior of concrete externally confined by composite jackets. Constr. Build. Mater., 2005. 19(3):p.223–232.

Yalcin, C.; Kaya, O. and Sinangil, M., Seismic retrofitting of RC columns having plain rebars using CFRP sheets for improved strength and ductility. Constr. Build. Mater., 2008. 22(3):p.295–307.

Barros, J.A.O. and Ferreira, D.R.S.M., Assessing the efficiency of CFRP discrete confinement systems for concrete column elements. J. Compos. Constr., 2008. 12(2):p.134– 148.

De Lorenzis, N.A. and Antonio, L.T., Strengthening of Reinforced Concrete Structures with Near-Surface Mounted FRP rods. International Meeting on Composite Materials, PLAST 2000, Milan, Italy.

De Lorenzis, L. and Nanni, A., Shear Strengthening of Reinforced Concrete Beams with Near-Surface Mounted Fiber Reinforced Polymer Rods. ACI Structural Journal, 2001. 98(1): p. 60-68.

Khalifa, A.; Alkhrdaji, T.; Nanni, A. and Lansburg, S., Anchorage of Surface Mounted FRP Reinforcement. Concrete International: Design and Construction, 1999. 21(10): p 49-54.

El-Hacha, R. and Rizkalla, S.H., Near-surface-mounted fiber reinforced polymer reinforcements for flexural strengthening of concrete structures. ACI Struct. J., 2004. 101(5):p.717–726.

Barros, J.A.O. and Fortes, A.S., Flexural strengthening of concrete beams with CFRP laminates bonded into slits. Cem. Concr. Compos., 2005. 27(4):p.471–480.

De Lorenzis, L. and Teng, J.G., Near-surface mounted FRP reinforcement: An emerging technique for strengthening structures. Composites, 2007. Part B, 38:p.119–142.

Bonaldo, E.; Barros, J.A.O. and Lourenço, P. B., Efficient strengthening technique to increase the flexural resistance of existing RC slabs. J. Compos. Constr., 2008. 12(2):p.149–159.

Perrone, M.; Joaquim, A.O.B and Alessandra, A., CFRP-Based Strengthening Technique to Increase the Flexural and Energy Dissipation Capacities of RC Columns. J. Compos. Constr., 2009. 13(5):p.372–383.


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