Title:
Simulation of Delamination Failures in RC Members Strengthened with CFRP Rod Panels and CFRP Laminates
Author(s):
Akram Jawdhari and Issam Harik
Publication:
Symposium Paper
Volume:
327
Issue:
Appears on pages(s):
5.1-5.20
Keywords:
Flexural strengthening; CFRP; rod panels; laminates; finite element; bond-slip relation; plate-end debonding; intermediate crack-induced debonding, concrete cover separation
DOI:
10.14359/51713325
Date:
11/1/2018
Abstract:
Fiber reinforced plastics (FRPs) have become a first choice for strengthening/repairing concrete members deficient in shear, flexure or torsion. However, oftentimes, the desired increase in capacity of FRP repaired/strengthened member is not achieved due to premature failures that occur at loads lower than the loads associated with failure of constituent materials (concrete, steel, FRP). Examples of premature failures in FRP retrofitted concrete applications include (1) plate-end debonding, (2) intermediate crack induced debonding (ICID), and (3) concrete cover separation (CCS). This paper present three-dimensional finite element (FE) models developed mainly to demonstrate the capability of FE models in predicting such failures, and to serve as reference for future FE studies concerning the behavior of RC members bonded to FRP reinforcement. Five RC beams, tested in previous experimental study by the authors, are modeled. The beams include a control beam; beam strengthened with spliced CFRP rod panel, beam strengthened with spliced CFRP rod panel, anchored at panel’s ends with CFRP wraps; beam strengthened with one (full-length) CFRP laminate, and beam strengthened with lap-spliced CFRP laminate system. Results, including load mid-span deflection response, strain profile along FRP length, and failure modes, showed that the presented FE models can replicate the experiments and predict the various premature failures oftentimes observed with FRP retrofitted concrete members.
Related References:
1. Rizzo, A. and De Lorenzis, L. (2009). “Behavior and capacity of RC beams strengthened in shear with NSM FRP reinforcement”, Construction and Building Materials, Vol. 23, pp.1555–1567.
2. Hawileh, R. A., Abdella, M. H., Tanarslan, M. H., and Naser, M. Z. (2010). “Modeling of nonlinear cyclic response of shear-deficient RC T-beams strengthened with side bonded CFRP fabric strips”. Computers and Concrete, Volume 8, No. (2), pp 193-206.
3. Al-Mahmoud, F., A. Castel, T. Q. Minh and R. François (2015). "Reinforced Concrete Beams Strengthened with NSM CFRP Rods in Shear." Advances in Structural Engineering 18(10): 1563-1574.
4. Jawdhari, A. R, and Harik, I. (2016). ‘‘Evaluation of RC Beams Strengthened with Spliced CFRP Rod Panels.’’ Proceeding, Structural Faults & Repair 2016, 17-19 May 2016, Edinburgh, United Kingdom.
5. Jawdhari, A., Peiris, A., and Harik, I. (2016). “Bond Study on CFRP Rod Panels Externally Adhered to Concrete.” ASCE Journal of Composites for Construction, doi: 10.1061/(ASCE) CC.1943-561416.0000765
6. Cole, B., and Fam, A. (2006). “Flexural load testing of concrete-filled FRP tubes with longitudinal steel and FRP rebar”, ASCE J. Compos. Construct. 10 (2006) 161–171.
7. El-Mogy, M., El-Ragaby, A., and El-Salakawy, E. (2010). "Flexural Behavior of Continuous FRP-Reinforced Concrete Beams." ASCE Journal of Composites for Construction, 669-680. doi: 10.1061/(ASCE)CC.1943-5614.0000140
8. Abouzied, A., and Masmoudi, R. (2015a). “Structural performance of new fully and partially concrete-filled rectangular FRP-tube beams”, Construction and Building Materials, Volume 101, Part 1, 30 December 2015, Pages 652-660, ISSN 0950-0618.
9. Arduini, M., and Nanni, A., (1997), “Behavior of Precracked RC Beams Strengthened with Carbon FRP Sheets”, ASCE Journal of Composites for Construction, Vol. 1, No. 2, pp. 63-70.
10. Blanksvard, T., B. Taljsten and A. Carolin (2009). "Shear Strengthening of Concrete Structures with the Use of Mineral-Based Composites." Journal of Composites for Construction 13(1): 25-34.
11. El-Maaddawy, T. and A. S. El-Dieb (2011). "Near-Surface-Mounted Composite System for Repair and Strengthening of Reinforced Concrete Columns Subjected to Axial Load and Biaxial Bending." Journal of Composites for Construction 15(4): 602-614.
12. Eshwar, N., T. J. Ibell and A. Nanni (2005). "Effectiveness of CFRP Strengthening on Curved Soffit RC Beams." Advances in Structural Engineering 8(1): 55-68.
13. Florut, S. C., G. Sas, C. Popescu and V. Stoian (2014). "Tests on Reinforced Concrete Slabs with cut-out Openings Strengthened with Fibre-Reinforced Polymers." Composites Part B-Engineering 66: 484-493.
14. Arduini, M., and Nanni, A., (1997), “Behavior of Precracked RC Beams Strengthened with Carbon FRP Sheets”, ASCE Journal of Composites for Construction, Vol. 1, No. 2, pp. 63-70.
15. Alagusundaramoorthy, P., Harik, I. E., and Choo, C., (2003). "Flexural Behavior of R/C Beams Strengthened with Carbon Fiber Reinforced Polymer Sheets or Fabric." Journal of Composites for Construction 7(4): 292-301.
16. Al-Mahmoud, F., A. Castel, R. Francois and C. Tourneur (2009). "Strengthening of RC Members with Near-Surface Mounted CFRP Rods." Composite Structures 91(2): 138-147.
17. Badawi, M., and soudki, K (2009). “Flexural strengthening of RC beams with prestressed NSM CFRP rods – Experimental and analytical investigation”, Construction and Building Materials, Volume 23, Issue 10, October 2009, Pages 3292–3300.
18. Jawdhari, A. R, and Harik, I. (2015). ‘‘Development Length and Bond Strength of CFRP Rod Panels (CRPs) Bonded to Concrete.’’ Proceeding, the 12th International Symposium on Fiber Reinforced Polymers for Reinforced Concrete Structures (FRPRCS-12) & the 5th Asia-Pacific Conference on Fiber Reinforced Polymers in Structures (APFIS-2015) joint conference, 14-16 December 2015, Nanjing, China.
19. Jawdhari, A., Peiris, A., and Harik, I. (2016). “Bond Study on CFRP Rod Panels Externally Adhered to Concrete.” Journal of Composites for Construction, doi: 10.1061/(ASCE) CC.1943-561416.0000765
20. Smith, S.T. and Teng, J.G. (2002a). “FRP-strengthened RC structures. I: Review of debonding strength models”, Engineering Structures, Vol. 24, No. 4, pp. 385–395.
21. Gao B, Leung C.K.Y, and Kim J.K. (2005). “Prediction of concrete cover separation failure for RC beams strengthened with CFRP strips”. Engineering Structures 2005; 27(2):177–89.
22. Yao J, and Teng J.G. (2007) “Plate end deponding in FRP-plated RC beams-I: Experiments”. Engineering Structures 2007; 29(2):2457–2471
23. Saadatmanesh H and Ehsani M R (1991). “RC Beams Strengthened with GFRP Plates I: Experimental Study”, J Struct Eng 117(11) 3417–3433.
24. Jumaat, M. Z., Alam, Md. A. (2008). "Strengthening of R.C. Beams Using Externally Bonded Plates and Anchorages." Australian Journal of Basic and Applied Sciences 3(3): 2207-2211.
25. Pan, J., and Leung, C. K. Y. (2008). "Effect of End Tapering on Crack-Induced FRP Debonding from the Concrete Substrate.", ASCE, Journal of Composites for Construction 12(1): 15-24.
26. ACI Committee 440 (2008), “Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures”, American Concrete Institute, Detroit.
27. Jawdhari, A., (2016). “Behavior of RC Beams Strengthened in Flexure with Spliced CFRP Rod Panels,” Ph.D. Dissertation, University of Kentucky. DOI: http://dx.doi.org/10.13023/ETD.2016.113
28. Teng, J. G., S. T. Smith, J. Yao and J. F. Chen (2003). "Intermediate Crack-Induced Debonding in RC Beams and Slabs." Construction and Building Materials 17(6-7): 447-462.
29. Park, J. G., K. M. Lee, H. M. Shin and Y. J. Park (2007). "Nonlinear Analysis of RC Beams Strengthened by Externally Bonded Plates." Computers and Concrete 4(2): 119-134.
30. Teng, X. D. and Y. X. Zhang (2014). "Nonlinear Finite Element Analyses of FRP-Strengthened Reinforced Concrete Slabs using a New Layered Composite Plate Element." Composite Structures 114: 20-29.
31. Obaidat, Y.T. (2010). “Structural Retrofitting of Reinforced Concrete Beams using Carbon Fiber Polymer.” Licentiate dissertation, Structural Mechanics, Lund, Sweden, ISSN 0281-6679.
32. Omran, H. Y. and R. El-Hacha (2012). "Nonlinear 3D Finite Element Modeling of RC Beams Strengthened with Prestressed NSM-CFRP Strips." Construction and Building Materials 31: 74-85.
33. 20. ANSYS (2012). Release 14.5 Documentation for ANSYS. Version 14.5, ANSYS Inc., Canonsburg, PA, USA.
34. Lu, X.Z., Teng, J.G., Ye, L.P., and Jiang, J.J. (2005). “Bond-slip models for FRP sheets/plates bonded to concrete.” Engineering Structures, Vol. 27, No. 6, pp. 920-937.
35. ACI 318-14 (2014). “Building Code Requirements for Reinforced Concrete,” American Concrete Institute, ISO# 193382007E.