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APFIS2017 - 6 Asia-Pacific Conference on FRP in Structures
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Singapore, 19-21 July 2017
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Therefore, the CFRP-strengthened RC slabs had sufficient capacity to resist the new live load of 6 kN/m
imposed be the machinery.
Figure 3. (a) FE mesh of RC slab, (b) mid-span deflection of slab, and (c) predicted vs measured field
live load deflection
6. Concluding remarks
This paper presented details of the FRP strengthening of the RC slabs of a full-scale 3 storey
reinforced concrete (RC) building. The original building (completed in 2015) is currently used as a
major processing facility for animal food production in Thailand. Design verifications based on ACI
318 showed that the flexural capacity of the original RC slab was insufficient. Based on the case study
discussed in this paper, the following conclusions can be drawn:
Design verifications based on ACI 318 showed that the flexural capacity of the original RC slab
st
was insufficient due to an increase of superimposed loads from machinery at the 1 floor.
Conversely, flexural, shear and torsional capacity of the existing RC beam and column sections
st
were sufficient to resist superimposed loads of up to 150% on the 1 floor
Externally bonded CFRP systems was successfully to increase the total flexural capacity of
original slabs by up to 150% compared to their original design capacity. The strengthening was
implemented adding minimum weight to the structure (120 kg of CFRP plates) and at a modest
cost (USD 2,000).
Live load midspan slab deflections from finite element analysis and field measurement were
lower than the allowable values specified by ACI 318-05. Therefore, the CFRP-strengthened RC
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slabs were deemed sufficient to resist the new imposed live load a 6 kN/m .
References
[1] A. Nanni. Fiber reinforced polymer composites for infrastructure strengthening - From research
to practice, VII AIMAT Congress, Ancona, Italy, June 29 - July 2, Keynote Paper KP2, 10 pp.
2004.
[2] C.E. Bakis, L.C. Bank, V.L. Brown, E. Cosenza, J.F. Davalos, J.J. Lesko, A. Machida, S.H.
Riskalla, T.C. Triantafillou. Fiber-reinforced polymer composites for construction – State-of-the-
art review, Journal of Composites for Construction. 6 (2), May, pp. 73-87.2002.
[3] ACI 440.2R-08. Guide for the Design and Construction of Externally Bonded FRP Systems for
Strengthening Concrete Structures, Reported by ACI Committee 440, American Concrete
Institute, Farmington Hills, 2008.
[4] fib Bulletin 14. Externally Bonded FRP Reinforcement for RC Structures. fib Task Group 9.3,
Lausanne, pp. 1–138. 2001.
[5] ACI 318-05. Building Code Requirements for Structural concrete and Commentary, B.M Johnson
and A.H. Wilson, Terminology of Building Conservation Industry, Division of Building
Research, NRC Canada, 2005.
[6] Hibbitt, Karlsson & Sorensen. ABAQUS User’s Manual, Version 6.13, 2013.
“Innovative Seismic Strengthening System for Concrete Structures”
© 2017 | T Imjai & R. Garcia (Eds.)
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