Keywords: finite element methods, fibre reinforced concrete, shear behaviour, reinforced concrete sections.

Shear failure is a controversial topic in the design of reinforced concrete sections because it is catastrophic and occurs suddenly with little or no warning prior to collapse. A beam with a relatively small span-to-depth ratio is normally known as a deep beam. There are many kinds of structural application of reinforced concrete deep beams such as transfer girders in tall buildings, long span structures, pile caps and water tanks [1,2]. The research reported in this paper used steel, synthetic, or hybrid fibres to enhance the shear capacity of reinforced concrete (RC) deep beams. Crimped polypropylene fibres have significantly increased the ultimate shear strength by up to 45%. With the used of flat-end steel fibres, the ultimate load has been improved by 28-107% at varying fibre contents. Hybrid fibres also performed very well in enhancing the shear capacity of RC deep beams. Fibre reinforced concrete (FRC) deep beams are more ductile and failed with a higher amount of energy absorption when compared to plain RC deep beams. The presence of fibre reinforcements in the concrete specimens restricts the propagation of cracks and allows more uniform cracking. The modified Willam and Warnke [3] five parameter model has been used to simulate the concrete matrix [4,5,6]. The numerical model has shown to provide accurate predictions for the load-deflection behaviour of FRC deep beams where good correlations were obtained.

1

R.H. Shah, S.V. Mishra, "Crack and Deformation Characteristics of SFRC Deep Beams", The Institution of Engineers (India) Technical Journals: Civil Engineering, 85, 44-48, 2004.

2

S.K. Madan, G.R. Kumar, S.P. Singh, "Steel Fibers as Replacement of Web Reinforcement for RCC Deep Beams in Shear", Asian Journal of Civil Engineering (Building and Housing), 8(5), 479-489, 2007.

3

K.J. Willam, E.D. Warnke, "Constitutive Model for the Triaxial Behavior of Concrete", Proceedings of International Association for Bridge and Structural Engineering, 19, ISMES, Bergamo, Italy, 174, 1975.

4

C.S. Chin, "Experimental and Computational Analysis of Fibre Reinforced Cementitious Composites", PhD Thesis, Civil and Computational Engineering Centre, Department of Civil Engineering, School of Engineering, University of Wales Swansea, 2006.

5

R.Y. Xiao, C.S. Chin, "Finite Element Modelling of Fibre Reinforced Concrete Structures", in B.H.V. Topping, L.F. Costa Neves, R.C. Barros, (Editors), "Trends in Civil and Structural Engineering Computing", Saxe-Coburg Publications, Stirlingshire, UK, Chapter 6, 131-148, 2009. doi:10.4203/csets.22.6

6

C.S. Chin, R.Y. Xiao, "Experimental and Computational Analysis of Fibre Reinforced Concrete Beams", Proceedings of the 11th International Conference on Non-conventional Materials and Technologies (NOCMAT 2009), Bath, UK, 140, 2009.

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