Effect of embedment length of untreated natural fibres on the bond behaviour in cement mortar

Abstract

The present investigation is focused on studying the effects of various matrices with 1:3, 1:4 and 1:5 mortars and fibre types of sisal and coir on the bond behavior at various ages of curing, i.e., 24 h, 3 d, 7 d and 28 d. The other parameters included in the investigation are water/cement (w/c) ratio, sand gradation and embedment length of fibres. In addition, the type of failure of sisal and coir fibres for different mixes of mortars at various curing ages is also reported. From the results, it is seen that the bond strength is improving with respect to age of curing in case of sisal fibres, but decreases in case of coir fibres. The failure of fibres due to fibre fracture is observed in sisal fibres and fibre pullout is observed in coir fibres. The other varying parameters such as mortar mixes, sand gradation, w/c ratio and embedded length also showed significant effect on bond behaviour of sisal and coir fibre with the cement mortar mixes.

Keywords

bond strength / cement mortar / natural fibre / pullout test / type of failure

References

[1] Bindiganavila V, Banthia N. Polymer and steel reinforced cementitious composites under impact loading– Part I: Bond-slip response. ACI Materials Journal, 2001, 98: 10–16

[2] Cunha V M C F, Barros J A O, Sena-cruz J M. Pullout behaviour of steel fibres in self-contacting concrete. Journal of Materials in Civil Engineering, 2010, 22: 1–9

[3] Naaman A E. Najm H. Bond-slip mechanisms of steel fibres in concrete. ACI Materials Journal, 1991, 88: 135–145

[4] Savastano H, Agopyan V. Transition zone studies of vegetable fibre-cement paste composites. Cement and Concrete Composites, 1999, 21: 49–57

[5] Mandel J A, Sun W, Said S. Studies of properties of the fibres-matrix interface in steel fibre reinforced mortar. ACI Materials Journal, 1987, 84: 205–216

[6] Shannag J M. Brincker R, Hansen W. Interfacial (fibre-matrix) properties of high strength mortar from fibre pullout. ACI Materials Journal, 1996, 93: 480–486

[7] Naaman A E, Shah S P. Pull-out mechanism in steel fibre reinforced concrete. Journal of the Structural Division, 1976, 19: 1537–1548

[8] Bentur A, Mindest S, Diamond S. Pullout processes in steel fibre reinforced cement. International journal of cement composites and lightweight concrete, 1985, 7: 29–37

[9] Naaman A E, Namur G G, Alwan J M, Najm H S. Fibre pullout and bond slip. I: Experimental validation. Journal of Structural Engineering, 1991, 17: 2791–2799

[10] Peled A, Bentur A, Yankelevsky D Z. The nature of bond between monofilament polyethylene yarns and cement matrices. Cement and Concrete Composites, 1998, 20: 319–327

[11] Sueki S, Soranakom C, Mobaser B, Peled A. A pullout-slip response of fabrics embedded in a cement paste matrix. Journal of Materials in Civil Engineering, 2007, 104: 933–941

[12] Morrissey F E, Coutts R S P, Grossman P U A. Bond between cellulose fibres and cement. The international journal of cement composites and lightweight concrete, 1985, 7: 73–80

[13] Ali M, Li X, Chouw N. Experimental investigations on bond strength between coconut fibre and concrete. Materials & Design, 2013, 44: 596–605

[14] Das B R, Banerjee P K. Interface bond and compatibility of jute with asphalt. Composites. Part A, Applied Science and Manufacturing, 2013, 53: 9–75

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