Structural Engineering and Mechanics

  • 제84권3호
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  • Pages.375-391
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  • 2022
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Mechanical behaviour between adjacent cracks in CFRP plate reinforced RC slabs

  • Yuan, Xin (School of Civil Engineering, Suzhou University of Science and Technology) ;
  • Bai, Hongyu (School of Civil Engineering, Suzhou University of Science and Technology) ;
  • Sun, Chen (School of Science, Nanjing University of Science and Technology) ;
  • Li, Qinqing (School of Civil Engineering, Suzhou University of Science and Technology) ;
  • Song, Yanfeng (School of Civil Engineering, Suzhou University of Science and Technology)
  • 투고 : 2021.10.26
  • 심사 : 2022.09.18
  • 발행 : 2022.11.10
⟨ 이전 논문 다음 논문 ⟩

초록

This paper discussed and analyzed the interfacial stress distribution characteristic of adjacent cracks in Carbon Fiber Reinforced Polymer (CFRP) plate strengthened concrete slabs. One un-strengthened concrete test beam and four CFRP plate-strengthened concrete test beams were designed to carry out four-point flexural tests. The test data shows that the interfacial shear stress between the interface of CFRP plate and concrete can effectively reduce the crack shrinkage of the tensile concrete and reduces the width of crack. The maximum main crack flexural height in pure bending section of the strengthened specimen is smaller than that of the un-strengthened specimen, the CFRP plate improves the rigidity of specimens without brittle failure. The average ultimate bearing capacity of the CFRP-strengthened specimens was increased by 64.3% compared to that without CFRP-strengthen. This indicites that CFRP enhancement measures can effectively improve the ultimate bearing capacity and delay the occurrence of debonding damage. Based on the derivation of mechanical analysis model, the calculation formula of interfacial shear stress between adjacent cracks is proposed. The distributions characteristics of interfacial shear stress between certain crack widths were given. In the intermediate cracking region of pure bending sections, the length of the interfacial softening near the mid-span cracking position gradually increases as the load increases. The CFRP-concrete interface debonding capacity with the larger adjacent crack spacing is lower than that with the smaller adjacent crack spacing. The theoretical calculation results of interfacial bonding shear stress between adjacent cracks have good agreement with the experimental results. The interfacial debonding failure between adjacent cracks in the intermediate cracking region was mainly caused by the root of the main crack. The larger the spacing between adjacent cracks exists, the easier the interfacial debonding failure occurs.

키워드

과제정보

This work was financially supported by the Brand Professional Funding Project of Jiangsu Province (Grant No. PPZY2015B143), the National Natural Science Foundation of China (Grant No. 51508368), the Science and Technology Project of Housing and Urban-Rural Development Department of Jiangsu Province(Grant No.2019ZD010), the Jiangsu Postgraduate Research and Innovation Program (Grant No. KYCX21_3027), the Jiangsu Province Graduate Student Practice Innovation Program Project (Grant No. SJCX21_1416), and the Key Project of Innovation and Entrepreneurship of College students in Jiangsu Province (Grant No. 201810332019Z).

참고문헌

  1. Ahmed, S., Yaqub, M.A. and Elahi, A. (2018), "Shear behaviour of pile cap strengthened with carbon fibre reinforced polymers", Proceedings of the Institution of Civil Engineers-Structures and Buildings, 1-11. https://doi.org/10.1680/jstbu.17.00136.
  2. Perez Caldentey, A., Padilla, P., Muttoni, A. and Fernandez Ruiz, M. (2012), "Effect of load distribution and variable depth on shear resistance of slender beams without stirrups", ACI Struct. J., 109, 595-603. https://doi.org/10.14359/51684037.
  3. Arduini, M. and Nanni, A. (1997), "Behavior of precracked RC beams strengthened with carbon FRP Sheets", J. Compos. Constr., 1, 63-70. https://doi.org/10.1061/(ASCE)1090-0268(1997)1:2(63).
  4. Bentz, E.C. Vecchio, F.J. and Collins, M.P. (2006), "Simplified modified compression field theory for calculating shear strength of reinforced concrete elements", ACI Struct. J., 103(4), 614-624.
  5. Chen, J.F., Yuan, H. and Teng, J.G. (2007), "Debonding failure along a softening FRP-to-concrete interface between two adjacent cracks in concrete members", Eng. Struct., 29(2), 259-270. http://doi.org/10.1016/j.engstruct.2006.04.017.
  6. Chen, X.C., Ding, M.B., Zhang, X.Y., Liu, Z.W. and Ma, H.J, (2018), "Experimental investigation on seismic retrofit of gravity railway bridge pier with CFRP and steel materials", Constr. Build. Mater., 182, 371-384. http://doi.org/10.1016/j.conbuildmat.2018.06.102.
  7. Fernandez Ruiz, F. and Muttoni, A. (2009), "Applications of the critical shear crack theory to punching of R/C slabs with transverse reinforcement", ACI Struct. J., 106(4), 485-494.
  8. Fernandez Ruiz, M., Muttoni, A. and Sagaseta, J. (2015), "Shear strength of concrete members without transverse reinforcement: A mechanical approach to consistently account for size and strain effects", Eng. Struct., 99, 360-372. http://doi.org/10.1016/j.engstruct.2015.05.007.
  9. Ghannadpour, S.A.M. and Shakeri, M. (2018), "Energy based collocation method to predict progressive damage behavior of imperfect composite plates under compression", Lat. Am. J. Solid. Struct., 15(4), http://doi.org/10.1590/1679-78254257.
  10. Gillich, G.R., Maia, N.M.M., Mituletu, I.C., Tufoi, M., Iancu, V. and Korka, Z. (2016), "A new approach for severity estimation of transversal cracks in multi-layered beams", Lat. Am. J. Solid. Struct., 13(8), 1526-1544. http://doi.org/10.1590/1679-78252541.
  11. Hasnat, A., Islam, M.M. and Amin, A.F.M.S. (2016), "Enhancing the debonding strain limit for CFRP strengthened RC beams using U-clamps: Identification of design parameters", J. Compos. Constr., 20(1), 04015039. http://doi.org/10.1061/(asce)cc.1943-5614.0000599.
  12. Li, K., Cao, S., Yang, Y. and Zhu, J. (2018), "Bond-slip relationship for CFRP sheets externally bonded to concrete under cyclic loading", Mater., 11, 336-349. http://doi.org/10.3390/ma11030336.
  13. Maya, L.F., Fernandez Ruiz, M., Muttoni, A. and Foster, S.J. (2012), "Punching shear strength of steel fibre reinforced concrete slabs", Eng. Struct., 40, 93-104. https://doi.org/10.1016/j.engstruct.2012.02.009.
  14. Muttoni, A (2003), "Shear and punching strength of slabs without shear reinforcement", Beton-und Stahlbetonbau, 98, 74-84. https://doi.org/10.1002/best.200300400
  15. Muttoni, A. (2008), "Punching shear strength of reinforced concrete slabs without transverse reinforcement", ACI Struct. J., 105(4), 440-450.
  16. Muttoni, A., Ruiz, M.F., Bentz, E., Foster, S. and Sigrist, V. (2013), "Background to the model code 2010 shear provisions-Part II Punching shear", Struct. Concrete, 14(3), 195-203. https://doi.org/10.1002/suco.201200064.
  17. Muttoni, A. and Schwartz, J. (1991), "Behaviour of beams and punching in slabs without shear reinforcement", IABSE Colloquium., 62, 703-708.
  18. Muttoni, A. and Fernandez Ruiz, M. (2008), "Shear strength of members without transverse reinforcement as function of critical shear crack width", ACI Struct. J., 105(2), 163-172.
  19. Rabinovich, O. and Frostig, Y. (2000), "Closed-form high-order analysis of RC beams strengthened with FRP strips", J. Compos. Constr., 4, 65-74. https://doi.org/10.1061/(ASCE)1090-0268(2000)4:2(65).
  20. Rahimi, H. and Hutchinson, A. (2001), "Concrete beams strengthened with externally bonded FRP plates", J. Compos. Constr., 5(1), 44-56. https://doi.org/10.1061/(asce)1090-0268(2001)5:1(44).
  21. Sakin, S., Anil, O., Ghoroubi, R. and Mercimek, O. (2018), "Modelling bond between concrete and bonded and anchored carbon-fibre polymer strips", Proc. Inst. Civil Eng.-Struct. Build., 172(6), 437-450. http://doi.org/10.1680/jstbu.18.00003.
  22. Sebastian, W.M. (2001), "Significance of midspan debonding failure in FRP-plated concrete beams", J. Struct. Eng., 127(7), 792-798. https://doi.org/10.1061/(ASCE)0733-9445(2001)127:7(792).
  23. Yuan, H., Teng, J.G., Seracino, R., Wu, Z.S. and Yao, J. (2004), "Full-range behavior of FRP-to-concrete bonded joints", Eng. Struct., 26(5), 553-565. http://doi.org/10.1016/j.engstruct.2003.11.006.
  24. Bencardino, F., Spadea, G. and Swamy, R.N. (2002), "Strength and ductility of reinforced concrete beams externally reinforced with carbon fiber fabric", Struct. J., 99(2), 163-171.
  25. Yuan, X., Zhu, C., Hu, J. and Zhang, Y. (2019), "Crack and mechanical behavior of CFRP plate-reinforced bridge roofs under high temperature with different anchoring measures", Lat. Am. J. Solid. Struct., 16, https://doi.org/10.1590/1679-78255575.
  26. Lu, X., Ye, L., Teng, J. and Zhuang, J. (2005). "Bond-slip model for FRP-to-concrete interface", J. Build. Struct., 26(4), 10-18. http://doi.org/10.1080/02726340590910084.
  27. Teng, J.G., Chen, G.M., Chen, J.F., Rosenboom, O.A. and Lam, L. (2009), "Behavior of RC beams shear strengthened with bonded or unbonded FRP wraps", J. Compos. Constr., 13(5), 394-404. http://doi.org/10.1061/(ASCE)CC.1943-5614.0000040.
  28. Teng, J.G., Yuan, H. and Chen, J.F. (2006), "FRP-to-concrete interface between two adjacent cracks: Theoretical model for debonding failure", Int. J. Solid. Struct., 43(18-19), 5750-5778. http://doi.org/10.1016/j.ijsolstr.2005.07.023.
  29. Ye, L.P, Fang, T.Q., Yang, Y.X. and Yue, Q.R. (2003), "Experimental research of flexural debonding perforamnce about RC beams strengthened with CFRP sheets", Build. Struct., 2, 61-65.
  30. Yuan, H., Teng, J.G., Seracino, R., Wu, Z.S. and Yao, J. (2004), "Full-range behvior of FRP-to-concrete bonded joints", Eng. Struct., 26(5), 553-565. https://doi.org/10.1016/j.engstruct.2003.11.006
  31. Yuan, X., Zhu, C.Y., Zheng, W. and Tang, B.J. (2019), "Experimental and numerical investigation on carbon fiber-reinforced polymer-strengthened concrete beam after high-temperature action of asphalt paving construction", Adv. Civil Eng., 2019, Article ID 1939585. https://doi.org/10.1155/2019/1939585.