Flexural retrofitting of the damaged reinforced concrete beams by using HPFRCC

Document Type : Article

Authors

Faculty of Civil Engineering, Semnan University, Semnan, Iran

Abstract

Damaged structures are not usually reliable to tolerate designed loads and therefor, need to retrofit in structural parts. The main purpose of this paper is to utilize HPFRCC as a high-performance material to recover the damaged beams and improve their ductility and moment capacity with experimental approaches. In addition to, a retrofitting method is presented using high-performance fibre reinforced cement-based composite (HPFRCC). The experimental study is performed on three simply supported beams with the same dimension, materials, and reinforcement configuration. The first beam, which is known as the reference beam (RC), is subjected to pure bending condition till its failure and the others are prone to a certain amount of load according to the final capacity of the first beam. Thereafter, two damaged beams are retrofitted using HPFRCC in the created grooves on tensile surface of the beam and finally these retrofitted beams are loaded to determine the bending behaviour. Experimental Results demonstrate that retrofitting can improve the first crack strength, load at yield condition, and maximum load capacity. Also, the proposed method increases the ductility and energy absorption of retrofitted beams.

Keywords


Refrences:
1. Shah, A.A. and Ribakov, Y. Recent trends in steel _bered high-strength concrete", Material Design, 32, pp. 4122{4151 (2011). 
2. Altun, F., Haktanir, T., and Ari, K. Effects of steel _ber addition on mechanical properties of concrete and RC beams", Construction and Building Material, 21(3), pp. 654{661 (2007). 
3. Obaidat, Y.T., Heyden, S., Dahlblom, O., Abu- Farsakh, G., and Abdel-Jawad, Y. Retro_tting of reinforced concrete beams using composite laminates", Construction and Building Material, 25(2), pp. 591{ 597 (2011). 
4. Ferreira, D., Bair_an, J., and Mar__, A. Numerical simulation of shear-strengthened RC beams", Engineering Structure, 46, pp. 359{374 (2013). 
5. Ferrari, V.J., Hanai, J.B., and De Souza, R.A. Flexural strengthening of reinforcement concrete beams using high performance _ber reinforcement cementbased composite (HPFRCC) and carbon _ber reinforced polymers (CFRP)", Construction and Building Materials, 48, pp. 85{498 (2013). 
6. Moatasem, M., Fayyadh, H., and Abdul, R. Analytical and experimental study on repair e_ectiveness of CFRP sheets for RC beams", Journal of Civil Engineering and Management, 20(1), pp. 21{31 (2014). 
7. Hamdy, M., Afefy, K.N., and Hussein, M. Enhancement of exural behavior of CFRP-strengthened reinforced concrete beams using engineered cementitious composites transition layer", Structure and Infrastructure Engineering Journal, 11(8), pp. 1042{1053 (2015). 
8. Ahmadpanahi, S.M. Experimental investigation RC beams using by new technology HPFRCC concretes", Master's Thesis, University of Semnan, Semnan, Iran (2014). 
9. Ghasemi Naghibdehi, M., Sharbatdar, M.K., and Mastali, M. Flexural performance of functionally graded RC cross-section with steel and PP _bres", Magazine of Concrete Research, 6(5), pp. 1{15 (2013). http://dx.doi.org/10.1680/macr.13.00248 
10. Hemmati, A., Kheyroddin, A., and Sharbatdar, M.K. Increasing the exural capacity of RC beams using partially HPFRCC layers", Computers and Concrete, 16(4), pp. 545{568 (2015). 
11. Hemmati, A., Kheyroddin, A., and Sharbatdar, M.K. Plastic hinge rotation capacity of reinforced HPFRCC beams", ASCE's Journal of Structural Engineering, 141(2), 04014111 (2015). http://dx.doi.org/10.1061/(ASCE)ST.1943-541X.000 0858 
12. Hemmati, A., Kheyroddin, A., and Sharbatdar, M.K. Using HPFRCC for increasing the capacity of R.C. frame", Sharif Journal, Civil Engineering, 3, pp. 97{ 106 (2013). 
13. Roumaldi, J.P. and Gordon, B.B., Mechanics of Crack Arrest in Concrete, SP-249-12 (2008). 
14. Romualdi, J.P. and James, A.M. Tensile strength of concrete a_ected by uniformly distributed and closely spaced short lengths of wire reinforcement", ACI Journal Proceedings, 61(6) (1964). 
15. Sheikh, S.H., DeRose, D., and Mardukhi, J. Retrofitting of concrete structures for shear and exure with _ber-reinforced polymers", ACI Structural Journal, 99(4), pp. 451{459 (2002). 16. Li, V.C. and Wu, H.C. Conditions for pseudo strainhardening in fiber reinforced brittle matrix composites", J. Appl. Mech. Rev. 45, pp. 390{398 (1992). 
17. Naaman, A.E. and Reinhardt, H.W. Characterization of high-performance _ber reinforced cement composites", in: Proc. HPFRCC-2, pp. 1{24 (1996). 
18. Fischer, G. and Li, V.C. Structural composites with ECC", in: Proc. ASCCS-6, pp. 1001{1008 (2000). 
19. Naaman, A.E., and Reinhardt, H.W. High performance fiber reinforced cement composites", HPFRCC- 4, International RILEM Report, Materials and Structures, 36, pp. 710{712 (2004). 
20. Li, J. and Zhang, Y.X. Evolution and calibration of a numerical model for modeling of hybrid fiber M.K. Sharbatdar and J. Ayyubi/Scientia Iranica, Transactions A: Civil Engineering 27 (2020) 2680{2689 2689 ECC panels under high-velocity impact", Composite Structure, 93, pp. 2714{2722 (2011). 
21. Jeyasehar, A.C. and Balamuralikrishnan, R. Strengthening of structures by HPFRCC laminates", Asian Journal of Civil Engineering, 13(1), pp. 29{42 (2012). 
22. Suwannakarn, S.W. Post-cracking characteristics of high-performance _ber reinforced cementitious composites", PhD Thesis, University of Michigan (2009). 
23. Wang, S. Micromechanics based matrix design for engineered cementitious composites", PhD Thesis, University of Michigan (2005). 
24. William, K.J. and Warnke, E.P. Constitutive model for the triaxial behavior of concrete", IABSE Proc., Int. Association for Bridge and Structural Engineering, Zurich, 19 (1975). 
25. Kunieda, M. and Rokugo, K. Measurement of crack opening behavior within ECC under bending moment", in International RILEM Workshop HPFRCC in Structural Applications, pp. 313{322 (2006).