S. Choo Chin/N. Shafiq/M. Fadhil Nuruddin · Behaviour of RC beams with CFRP-strengthened openings
Table 5. Comparison of EXP and FEM results
EXP
FEM Ult. FEM/Ult. EXP
Beam
Yielding load Py (kN)
∆y (mm)
Ultimate load Pu (kN)
∆u (mm)
Yielding load Py (kN)
∆y (mm)
Ultimate load Pu (kN)
∆u (mm)
CB1
77
8.2
80
9.1
77
3.9
87
7.8
1.09
CB2
86
8.0
96
36.4
77
3.9
87
7.8
0.91
BEO
32
2.0
49
3.3
26
0.8
45
2.2
0.92
BRO
34
2.5
39
3.0
23
0.9
40
2.3
1.03
SBEO
62
3.7
77
5.3
36
0.7
64
1.5
0.83
SBRO
72
6.6
83
10.4
38
0.8
57
1.8
0.69
tion. This may be due to the incorporation of interfacial bond-slip action between the concrete and the CFRP in the FE analysis which failed by debonding once the FE simulation terminated due to a divergence.
7 Recommendations The following are the main recommendations for further work: 1. To study the dynamic behaviour of RC beams due to the effects of large openings (single or multiple) of various shapes and sizes subjected to critical shear, bending, torsion and combined loading in simply supported beams, T-beams, continuous beams and deep beams. 2. To investigate the effects of strengthening configurations using CFRP laminates on the dynamic behaviour of beams. 3. To study the failure modes of CFRP laminates around openings of various shapes, sizes and locations by way of both numerical analysis and experimental investigation. 4. To simulate/validate the beams using 3D FE analyses.
Acknowledgments The authors wish to express their gratitude and sincere appreciation to Universiti Teknologi PETRONAS (UTP) for financing this research work. The authors would also like to thank the laboratory technologists of the Concrete and Structural Laboratory, Civil Engineering Department, UTP for their assistance throughout the experimental work. Last but not least, the authors would like to thank Dr. Su Kong Ngien for his contribution in proofreading this paper. References 1. K.W. Nasser, A. Acavalos, and H.R. Daniel, “Behavior and Design of Large Openings in Reinforced Concrete Beams,” ACI Journal, Proceedings, vol. V.64, 1967, pp. 25–33. 2. G.B. Barney, J.M. Corley, W.G., Hanson, and R.A. Parmelee, “Behaviour and Design of Prestressed Concrete Beams with Large Web Openings,” PCI Journal, vol. 22, 1977, pp. 32–61. 3. H.S. Ragan and J. Warwaruk, “Tee Members with Large Web Openings,” Journal of the Prestressed Concrete Institute, vol. 12, 1967, pp. 52–65.
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