Stereo-digital image correlation in the behavior investigation of CFRP-steel composite members

  • Dai, Yun-Tong (Jiangsu Key Laboratory of Engineering Mechanics, Southeast University) ;
  • Wang, Hai-Tao (Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education, Southeast University) ;
  • Ge, Tian-Yuan (Jiangsu Key Laboratory of Engineering Mechanics, Southeast University) ;
  • Wu, Gang (Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education, Southeast University) ;
  • Wan, Jian-Xiao (School of Civil Engineering, Southeast University) ;
  • Cao, Shuang-Yin (School of Civil Engineering, Southeast University) ;
  • Yang, Fu-Jun (Jiangsu Key Laboratory of Engineering Mechanics, Southeast University) ;
  • He, Xiao-Yuan (Jiangsu Key Laboratory of Engineering Mechanics, Southeast University)
  • Received : 2016.04.21
  • Accepted : 2017.02.25
  • Published : 2017.04.30


The application of carbon fiber reinforced polymer (CFRP) in steel structures primarily includes two categories, i.e., the bond-critical application and the contact-critical application. Debonding failure and buckling failure are the main failure modes for these two applications. Conventional electrometric techniques may not provide precise results because of the limitations associated with single-point contact measurements. A nondestructive full-field measurement technique is a valuable alternative to conventional methods. In this study, the digital image correlation (DIC) technique was adopted to investigate the bond behavior and buckling behavior of CFRP-steel composite members. The CFRP-to-steel bonded joint and the CFRP-strengthened square hollow section (SHS) steel column were tested to verify the suitability of the DIC technique. The stereo-DIC technique was utilized to measure continuous deformation. The bond-slip relationship of the CFRP-to-steel interface was derived using the DIC data. Additionally, a multi-camera DIC system consisting of four stereo-DIC subsystems was proposed and applied to the compressive test of CFRP-strengthened SHS steel column. The precise buckling location and CFRP delamination of the CFRP-strengthened SHS steel column were identified. The experimental results confirm that the stereo-DIC technique can provide effective measurements for investigating the behaviors of CFRP-steel composite members.


CFRP;steel;bond behavior;buckling behavior;digital image correlation


Supported by : National Natural Science Foundation of China, Central Universities


  1. Abdelrahman, K. and El-Hacha, R. (2011), "Behavior of largescale concrete columns wrapped with CFRP and SFRP sheets", J. Compos. Constr., 16(4), 430-439.
  2. Ali-Ahmad, M., Subramaniam, K. and Ghosn, M. (2006), "Experimental investigation and fracture analysis of debonding between concrete and FRP sheets", J. Eng. Mech., 132(9), 914-923.
  3. Bakis, C.E., Bank, L.C., Brown, V.L., Cosenza, E., Davalos, J.F., Lesko, J.J. and Triantafillou, T.C. (2002), "Fiber-reinforced polymer composites for construction-state-of-the-art review", J. Compos. Constr., 6(2), 73-87.
  4. Bocciarelli, M., Colombi, P., Fava, G. and Poggi, C. (2009), "Prediction of debonding strength of tensile steel/CFRP joints using fracture mechanics and stress based criteria", Eng. Frac. Mech., 76(2), 299-313.
  5. Busca, D., Fazzini, M., Lorrain, B., Mistou, S., Karama, M. and Pastor, M.L. (2014), "High-speed stereo digital image correlation: application to biaxial fatigue", Strain, 50(5), 417-427.
  6. Daud, R.A., Cunningham, L.S. and Wang, Y.C. (2015), "Static and fatigue behaviour of the bond interface between concrete and externally bonded CFRP in single shear", Eng. Struct., 97, 54-67.
  7. Fagerholt, E., Borvik, T. and Hopperstad, O.S. (2013), "Measuring discontinuous displacement fields in cracked specimens using digital image correlation with mesh adaptation and crack-path optimization", Opt. Lasers Eng., 51(3), 299-310.
  8. Fawzia, S., Zhao, X.L. and Al-Mahaidi, R. (2010), "Bond-slip models for double strap joints strengthened by CFRP", Comp. Struct., 92(9), 2137-2145.
  9. Ghiassi, B., Xavier, J., Oliveira, D.V. and Lourenco, P.B. (2013), "Application of digital image correlation in investigating the bond between FRP and masonry", Compos. Struct., 106,340-349.
  10. Hadji, L., Daouadji, T.H., Meziane, M.A.A. and Bedia, E.A.A. (2016) , "Analyze of the interfacial stress in reinforced concrete beams strengthened with externally bonded CFRP plate", Steel Compos. Struct., Int. J., 20(2), 413-429.
  11. Ke, X.D., Schreier, H.W., Sutton, M.A. and Wang, Y.Q. (2011), "Error assessment in stereo-based deformation measurements", Exp. Mech., 51(4), 423-441.
  12. Kumar, R.L.V., Bhat, M.R. and Murthy, C.R.L. (2013), "Experimental analysis of composite single-lap joints using digital image correlation and comparison with theoretical models", J. Reinf. Plast. Comp., 32(23), 1858-1876.
  13. Liu, C., Chen, Z.N., Ding, L.N., Wu, G. and He, X.Y. (2013),"360-degree-full-surface digital image correlation system in civil engineering applications", Proceedings of Jointed Conference on International Conference on Experimental Mechanics 2013 and the 12th Asian Conference on Experimental Mechanics, Bangkok, Thailand, November.
  14. Malesa, M., Malowany, K., Tomczak, U., Siwek, B., Kujawinska, M. and Sieminska-Lewandowska, A. (2013), "Application of 3D digital image correlation in maintenance and process control in industry", Comput. Ind., 64(9), 1301-1315.
  15. Pan, B., Wu, D.F. and Yu, L.P. (2012), "Optimization of a threedimensional digital image correlation system for deformation measurements in extreme environments", Appl. Opt., 51(19), 4409-4419.
  16. Pan, B., Li, K. and Tong, W. (2013), "Fast, robust and accurate digital image correlation calculation without redundant computations", Exp. Mech., 53(7), 1277-1289.
  17. Park, J.W. and Yoo, J.H. (2015), "Flexural and compression behavior for steel structures strengthened with Carbon Fiber Reinforced Polymers sheet", Steel Compos. Struct., Int. J., 19(2), 441-465.
  18. Peters, W.H. and Ranson, W.F. (1982), "Digital imaging techniques in experimental stress analysis", Opt. Eng., 21(3), 213427-213427.
  19. PMLAB (2014), Digital Image Correlation Software PMLAB DIC-3D_2014a; Nanjing PMLAB*Sensor Tech. Co., Ltd., Nanjing, China.
  20. Shaat, A. and Fam, A.Z. (2006), "Axial loading tests on short and long hollow structural steel columns retrofitted using carbon fibre reinforced polymers", Can. J. Civil Eng., 33(4), 458-470.
  21. Shaat, A. and Fam, A.Z. (2009), "Slender steel columns strengthened using high-modulus CFRP plates for buckling control", J. Compos. Constr., 13(1), 2-12.
  22. Shao, X.X., Dai, X.J. and He, X.Y. (2015), "Noise robustness and parallel computation of the inverse compositional Gauss-Newton algorithm in digital image correlation", Opt. Lasers Eng., 71, 9-19.
  23. Shi, J.W., Zhu, H., Wu, Z.S., Seracino, R. and Wu, G. (2012), "Bond behavior between basalt fiber-reinforced polymer sheet and concrete substrate under the coupled effects of freeze-thaw cycling and sustained load", J. Compos. Constr., 17(4), 530-542.
  24. Sutton, M.A., Orteu, J.J. and Schreier, H. (2009), Image Correlation for Shape, Motion and Deformation Measurements: Basic Concepts, Theory and Applications, Springer Science & Business Media, LLC, New York, NY, USA.
  25. Teng, J.G., Yu, T. and Fernando, D. (2012), "Strengthening of steel structures with fiber-reinforced polymer composites", J. Constr. Steel Res., 78, 131-143.
  26. Wang, Y.Q., Sutton, M.A., Ke, X.D., Schreier, H.W., Reu, P.L. and Miller, T.J. (2011), "On error assessment in stereo-based deformation measurements", Exp. Mech., 51(4), 405-422.
  27. Wang, H.T., Wu, G., Dai, Y.T. and He, X.Y. (2016), "Determination of the bond-slip behavior of CFRP-to-steel bonded interfaces using digital image correlation", J. Reinf. Plast. Comp., 35(18), 1353-1367.
  28. Wu, C., Zhao, X.L., Duan, W.H. and Al-Mahaidi, R. (2012), "Bond characteristics between ultra high modulus CFRP laminates and steel", Thin-Wall. Struct., 51, 147-157.
  29. Xavier, J., De Jesus, A.M.P., Morais, J.J.L. and Pinto, J.M.T. (2012), "Stereovision measurements on evaluating the modulus of elasticity of wood by compression tests parallel to the grain", Constr. Build. Mater., 26(1), 207-215.
  30. Yu, T., Fernando, D., Teng, J.G. and Zhao, X.L. (2012), "Experimental study on CFRP-to-steel bonded interfaces", Compos. Part B, 43(5), 2279-2289.
  31. Zhao, X.L. and Zhang, L. (2007), "State-of-the-art review on FRP strengthened steel structures", Eng. Struct., 29(8), 1808-1823.
  32. Zhu, H., Wu, G., Shi, J.W., Liu, C. and He, X.Y. (2014), "Digital image correlation measurement of the bond-slip relationship between fiber-reinforced polymer sheets and concrete substrate", J. Reinf. Plast. Comp., 33(17), 1590-1603.