Abstract
This study investigates the performance of a case study reinforced concrete (RC) slab strengthened in flexure with Fibre Reinforced Polymer (FRP) sheets. The RC slab is at the top floor of a 17-storey building upon which three water tanks (of 1,000 l each) had to be built due to a change of use of the building's top floor. To assess the performance of the existing slab, site investigations and non-destructive testing (NDT) were carried out as per ACI 318 standards. To increase the load capacity of the slab, Externally Bonded Reinforcement (EBR) Carbon FRP sheets were bonded to the bottom of the RC slab. Following the strengthening intervention, the CFRP-strengthened slab was subjected to a 24-h load test (according to ACI 318) and to a Cyclic Load Test (following ACI 437) using an ad-hoc water pool built on top of the slab. The results from these tests (maximum and residual deflections of 0.92 mm and 0.34 mm, respectively) indicated that the CFRP-strengthened slab met satisfactorily the deflection criteria and performance indices of such tests. The CFRP-strengthened slab was then modelled and analysed in ANSYS® to calibrate and validate the experimental results. It is shown that the deflection and strains predicted by the finite element (FE) model match well the experimental measurements (errors < 15%), which confirms the suitability of the modelling approach adopted in ANSYS®. This article contributes towards the dissemination of real case studies of FRP-strengthened structures, which are scarce in the literature and thus can be useful to engineers and practitioners working in the field of structural strengthening.
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Acknowledgements
This work was supported by Walailak University, Research Assistant Grant No. 38/2024. The authors acknowledge the partially support provided by the Capacity Enhancement and Driving Strategies for Bilateral and Multilateral Cooperation for 2021 (Thailand and UK). The authors also acknowledge the support from Ministry of Higher Education Malaysia, Fundamental Research Grant Scheme (FRGS), No: 9003-00965.
Funding
The authors would like to acknowledge the support from Ministry of Higher Education Malaysia, Fundamental Research Grant Scheme (FRGS), No: 9003-00965. The project was supported by the Capacity Enhancement and Driving Strategies for Bilateral and Multilateral Cooperation for 2021 (between Thailand and United Kingdom).
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R.S. and T.I.: Conceptualization, Methodology, Software, Investigation; T.I., R.S., R. G.: Methodology, Software, Validation, Writing—Original Draft, Writing—Review & Editing; T.I. N.L.R.: Conceptualization, Methodology, Formal analysis, Validation, Writing—Original Draft, Writing—Review & Editing, Visualization; T.I. N.L.R., P. A.: Writing—Original Draft, Visualization; All authors reviewed the manuscript.
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Sridhar, R., Aosai, P., Imjai, T. et al. Performance of an EBR CFRP-strengthened RC slab using 24-h and cyclic load tests: a real case study. J Build Rehabil 9, 85 (2024). https://doi.org/10.1007/s41024-024-00428-0
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DOI: https://doi.org/10.1007/s41024-024-00428-0