DOI QR코드

DOI QR Code

Flexural strengthening of RC one way solid slab with Strain Hardening Cementitious Composites (SHCC)

  • Basha, Ali (Civil Engineering Department, Faculty of Engineering, Kafrelsheikh University) ;
  • Fayed, Sabry (Civil Engineering Department, Faculty of Engineering, Kafrelsheikh University) ;
  • Mansour, Walid (Civil Engineering Department, Faculty of Engineering, Kafrelsheikh University)
  • 투고 : 2019.09.25
  • 심사 : 2020.05.09
  • 발행 : 2020.05.25

초록

The main aim of the current research is to investigate the flexural behavior of the reinforced concrete (RC) slabs strengthened with strain hardening cementitious composites (SHCC) experimentally and numerically. Seven RC slabs were prepared and tested under four-points loading test. One un-strengthened slab considered as control specimen while six RC slabs were strengthened with reinforced SHCC layers. The SHCC layers had different reinforcement ratios and different thicknesses. The results showed that the proposed strengthening techniques significantly increased the ultimate failure load and the ductility index up to 25% and 22%, respectively, compared to the control RC slab. Moreover, a three dimensional (3D) finite element model was proposed to analyze the strengthened RC slabs. It was found that the results of the proposed numerical model well agreed with the experimental responses. The validated numerical model used to study many parameters of the SHCC layer such as the reinforcement ratios and the different thicknesses. In addition, steel connectors were suggested to adjoin the concrete/SHCC interface to enhance the flexural performance of the strengthened RC slabs. It was noticed that using the SHCC layer with thickness over 40 mm changed the failure mode from the concrete cover separation to the SHCC layer debonding. Also, the steel connectors prevented the debonding failure pattern and enhanced both the ultimate failure load and the ductility index. Furthermore, a theoretical equation was proposed to predict the ultimate load of the tested RC slabs. The theoretical and experimental ultimate loads are seen to be in fairly good agreement.

키워드

참고문헌

  1. Abbaszadeh, M.A., Sharbatdar, M.K. and Kheyroddin, A. (2017), "Performance of two-way RC slabs retrofitted by different configurations of high performance fibre reinforced cementitous composite strips", Open Civil Eng. J., 11, 650-663. https://doi.org/10.2174/1874149501711010650.
  2. Afefy, H. and El-Tony, M. (2019), "Punching shear resistance of strengthened reinforced concrete interior slab-column connections using ultra-high-performance strain hardening cementitious composite material", Adv. Struct. Eng., 22(8), 1799-1816. https://doi.org/10.1177/1369433218823841.
  3. Al-Osta, M.A., Isa, M.N., Baluch, M.H. and Rahman, M.K. (2017), "Flexural behavior of reinforced concrete beams strengthened with ultra-high performance fiber reinforced concrete", Constr. Build. Mater., 134, 279-296. https://doi.org/10.1016/j.conbuildmat.2016.12.094.
  4. Basha, A., Fayed, S. and Elsamak, G. (2019), "Flexural behavior of cracked RC beams retrofitted with strain hardening cementitious composites", KSCE J. Civil Eng., 23(6), 2644-2656. https://doi.org/10.1007/s12205-019-1874-4.
  5. Cheng, M.Y. and Parra-Montesinos, G.J. (2010), "Evaluation of steel fiber reinforcement for punching shear resistance in slab-column connections-part I: monotonically increased load", ACI Struct. J., 107, 101-109.
  6. Choi, K., Taha, M.R., Park, H. and Maji, A.K. (2007), "Punching shear strength of interior concrete slab-column connections reinforced with steel fibers", Cement Concrete Compos., 29, 409-420. https://doi.org/10.1016/j.cemconcomp.2006.12.003.
  7. ECP 203-2017 (2017), Design and Construction of Reinforced Concrete Structures.
  8. Esmaeeli, E. (2015), "Development of hybrid composite plate (HCP) for strengthening and repair of RC structures", Doctoral Thesis, University of Minho, Guimaraes, Portugal.
  9. Ganesana, N., Nidhi, M. and Indirac, P.V. (2015), "SFRHPC interior beam-column-slab joints under reverse cyclic loading", Adv. Concrete Constr., 3(3), 237-250. https://doi.org/10.12989/acc.2015.3.3.237.
  10. Hibbitt, Karlsson, and Sorensen, Inc. (2000), ABAQUS Theory Manual, User Manual and Example Manual, Version 6.7. Providence, RI, Simulia.
  11. Hussein, H., Kunieda, M. and Nakamura, H. (2012), "Strength and ductility of RC beams strengthened with steel-reinforced strain hardening cementitious composites", Cement Concrete Compos., 34(9), 1061-1066. https://doi.org/10.1016/j.cemconcomp.2012.06.004.
  12. Khalil, A., Etman, E., Atta, A. and Essam, M. (2017), "Behavior of RC beams strengthened with strain hardening cementitious composites (SHCC) subjected to monotonic and repeated loads", Eng. Struct., 140, 151-163. https://doi.org/10.1016/j.engstruct.2017.02.049.
  13. Kunieda, M., Hussein, M., Ueda, N. and Nakamura, H. (2010), "Fracture behavior of steel reinforced UHP-SHCC under axial tension", Proceedings FRAMCOS-7, 1557-1564.
  14. Martinola, G., Meda, A., Plizzari, G.A. and Rinaldi, Z. (2010), "Strengthening and repair of RC beams with fiber reinforced concrete", Cement Concrete Compos., 32(9), 731-739. https://doi.org/10.1016/j.cemconcomp.2010.07.001.
  15. Obaidat, Y.T., Heyden, S. and Dahlblom, O. (2010), "The effect of CFRP and CFRP/concrete interface model when modeling retrofitted RC beams with FEM", Comput. Struct., 92, 1391-1398. https://doi.org/10.1016/j.compstruct.2009.11.008.
  16. Qi, J., Wang, J. and Feng, Y. (2019), "Shear performance of an innovative UHPFRC deck of composite bridge with coarse aggregate", Adv. Concrete Constr., 7(4), 219-229. https://doi.org/10.12989/acc.2019.7.4.219.
  17. Radik, M.J., Erdogmus, E. and Schafer, T. (2011), "Strengthening two-way reinforced concrete floor slabs using polypropylene fiber reinforcement", J. Mater. Civil Eng., 23, 562-571. https://doi.org/10.1061/(ASCE)MT.1943-5533.0000206.
  18. Saenz, LP. (1964), "Discussion of "Equation for the stress-strain curve of concrete", ACI J., 61, 1229-1235.
  19. Sakr, M.A., Sleemah, A.A., Khalifa, T.M. and Mansour, W.N. (2019), "Shear strengthening of RC beams using prefabricated ultra-high performance fiber reinforced concrete (UHPFRC) plates: Experimental and numerical investigation", Struct. Concrete J., 20, 1137-1153. https://doi.org/10.1002/suco.201800137.
  20. Shin, S.K., Kim, J.J.H. and Lim, Y.M. (2007), "Investigation of the strengthening effect of DFRCC applied to plain concrete beams", Cement Concrete Compos., 29(6), 465-473. https://doi.org/10.1016/j.cemconcomp.2007.02.005.
  21. Yun, H.D., Kim, S.W., Lee, Y.O., Izuka, T., Sakaguchi, Y., Rokugo, K. and Lim, S.C (2010), "Crack width control of reinforced concrete one-way slabs utilizing expansive strain-hardening cement-based composites (SHCCs)", Proceedings FRAMCOS-7, 1565-1572.
  22. Zhang, Y. (2013), "Zero-span tensile model for evaluating cracking behavior of SHCC for RC flexural strengthening", Mag. Concrete Res., 65, 1486-1493. https://doi.org/10.1680/macr.13.00215.

피인용 문헌

  1. Experimental study on shear, tensile, and compression behaviors of composite insulated concrete sandwich wall vol.11, pp.1, 2020, https://doi.org/10.12989/acc.2021.11.1.033