Open Access Articles Peer Reviewed

Improving Composite Action in Circular CFST Columns Using Internal Spiral Plates

Authors 2
Published: 2026-08-04 Issue: Vol. 26 , No. 3 Pages: 1-11 Cite this article DOI: 10.56748/ejse.26990

Abstract

Numerous confinement techniques have been proposed to enhance the strength and ductility of circular concrete-filled steel tube (CFST) columns. This study introduces an innovative confinement method for short circular CFST columns incorporating internal spiral plate stiffeners. The rectangular spiral plates are attached to the inner surface of the steel tube such that their flat faces remain in direct contact with the tube wall. This configuration minimizes obstruction to concrete flow and ensures proper compaction without void formation during casting. The spiral plates were connected to the steel tube using intermittent external fillet welding and tested under axial compression to evaluate their influence on load-carrying capacity and deformation behavior. A detailed finite element (FE) model was developed to complement the experimental program and to investigate the effects of key parameters, including spiral pitch, plate width, and weld spacing, on axial performance. The results demonstrate that incorporating spiral plate stiffeners increases the ultimate strength by an average of 16% compared to conventional CFST columns. Strength enhancement ranged from 5% to 55% as the spiral pitch decreased from 150 mm to 25 mm, while reducing weld spacing from 180° to 30° improved strength by 6–10%. A normalized spiral pitch (p/D) ≤ 0.5 provided effective confinement, resulting in stable post-peak behavior and mitigation of local buckling. Increasing the spiral plate width up to 40 mm enhanced axial strength by approximately 22%, highlighting its contribution to improved load resistance. Furthermore, the spiral plates were effectively delayed and uniformly distributed local bulging along the column height.

Keywords

  • Concrete filled steel tube column
  • finite element analysis
  • confined CFST column
  • spiral plate stiffener
209 136

References

  1. Abbas, N. J., & Ali, A. A. (2021). Prediction of axial capacity of octagonal concrete-filled steel tube columns considering confinement effect. Int. J. Struct. Eng., 12(2), 170-188. DOI: https://doi.org/10.1504/IJSTRUCTE.2022.121891
  2. Alrebeh, S. K., Ahmed, A. D., Al-Asad, A. K., & Ekmekyapar, T. (2023). Experimental performance evaluation of concrete-filled steel tube columns confined by high-strength steel bolts. Int. J. Steel Struct., 23(4), 1135-1147. DOI: https://doi.org/10.1007/s13296-023-00755-x
  3. Alrebeh, S. K., & Ekmekyapar, T. (2019b). Structural performance of short concrete-filled steel tube columns with external and internal stiffening under axial compression. Structures, 20, 702-716. DOI: https://doi.org/10.1016/j.istruc.2019.06.015
  4. Alrebeh, S. K., & Ekmekyapar, T. (2019a). Structural behavior of concrete-filled steel tube short columns stiffened by external and internal continuous spirals. Structures, 22, 98-108. DOI: https://doi.org/10.1016/j.istruc.2019.07.001
  5. Arokiaprakash, A., & Selvan, S. (2022). An experimental behavior of the bond-slip performance of hybrid fiber concrete-filled steel tube columns with shear studs. Asian Journal of Civil Engineering, 24, 1-13. DOI: https://doi.org/10.1007/s42107-022-00510-3
  6. Arokiaprakash, A., & Senthil, S. S. (2023). Comprehensive study of compressive behavior of CFST columns with confinements and stiffeners. J. Constr. Steel Res., 211, 108127. DOI: https://doi.org/10.1016/j.jcsr.2023.108127
  7. Binici, B. (2005). An analytical model for stress-strain behavior of confined concrete. Eng. Struct., 27(7), 1040-1051. DOI: https://doi.org/10.1016/j.engstruct.2005.03.002
  8. Chen, J., Yang, Z. M., Hu, L., & Wang, J. (2023). Behavior of CFRP confined circular CFST columns reinforced with internal latticed steel angles under seismic loading. J. Constr. Steel Res., 208, 108033. DOI: https://doi.org/10.1016/j.jcsr.2023.108033
  9. Dabaon, M., El-Khoriby, S., El-Boghdadi, M., & Hassanein, M. F. (2009). Confinement effect of stiffened and unstiffened concrete-filled stainless-steel tubular stub columns. J. Constr. Steel Res., 65(8-9), 1846-1854. DOI: https://doi.org/10.1016/j.jcsr.2009.04.012
  10. de Oliveira, W. L. A., De Nardin, S., De Cresce, E. L. H., & El Debs, M. K. (2010). Evaluation of passive confinement in CFT columns. J. Constr. Steel Res., 66(4), 487-495. DOI: https://doi.org/10.1016/j.jcsr.2009.11.004
  11. Giakoumelis, G., & Lam, D. (2004). Axial capacity of circular concrete-filled tube columns. J. Constr. Steel Res., 60, 1049-1068. DOI: https://doi.org/10.1016/j.jcsr.2003.10.001
  12. Gupta, A., Mohan, R., Bisht, H., & Sharma, A. (2022). Experimental testing and numerical modelling of CFST columns under axial compressive load. Asian Journal of Civil Engineering, 23(3), 415-424. DOI: https://doi.org/10.1007/s42107-022-00432-0
  13. Guptha, P. K., Khaudhair, Z. A., & Ahuja, A. K. (2014). Computational study on performance of circular concrete-filled steel tubular columns. Int. J. Struct. Eng., 5(1), 76-91. DOI: https://doi.org/10.1504/IJSTRUCTE.2014.058685
  14. Guptha, P. K., Verma, V. K., Khaudhair, Z., & Singh, H. (2015). Effect of tube area on the behavior of concrete-filled tubular columns. Compt. Concrete, 15(2), 141-166. DOI: https://doi.org/10.12989/cac.2015.15.2.141
  15. Hamed, E., Younas, S., Li, D., & Uy, B. (2021). Behaviour of high strength concrete-filled short steel tubes under sustained loading. Steel Compos. Struct., 39(2), 159-170.
  16. Hoang, A. L., & Fehling, E. (2017). Numerical analysis of circular steel tube confined UHPC stub columns. Compt. Concrete, 19(3), 263-273. DOI: https://doi.org/10.12989/cac.2017.19.3.263
  17. Hu, C., Wang, Y., Cheng, R., Luo, J., & Gong, M. (2024). Confinement effect and stress-strain model for concrete of multi-cell CFST column under axial compression. J. Constr. Steel Res., 221, 108865. DOI: https://doi.org/10.1016/j.jcsr.2024.108865
  18. Hu, Y. M., Yu, T., & Teng, J. G. (2011). FRP-confined circular concrete-filled thin steel tubes under axial compression. J. Compos. Constr., 15(5), 850-860. DOI: https://doi.org/10.1061/(ASCE)CC.1943-5614.0000217
  19. Huang, C. S., Yeh, Y. K., Liu, G. Y., Hu, H. T., Tsai, K. C., Weng, Y. T., Wang, S. H., & Wu, M. H. (2002). Axial load behavior of stiffened concrete-filled steel columns. J. Struct. Eng., 128(9), 1222-1230. DOI: https://doi.org/10.1061/(ASCE)0733-9445(2002)128:9(1222)
  20. Lai, M. H., & Ho, J. C. M. (2014). Behaviour of uni-axially loaded concrete-filled-steel-tube columns confined by external rings. Struct. Design Tall Spec. Build., 23(6), 403-426. DOI: https://doi.org/10.1002/tal.1046
  21. Lai, M. H., & Ho, J. C. M. (2014). Confinement effect of ring-confined concrete-filled-steel-tube columns under uni-axial load. Eng. Struct., 67, 123-141. DOI: https://doi.org/10.1016/j.engstruct.2014.02.013
  22. Lai, M. H., & Ho, J. C. M. (2015). Axial strengthening of thin-walled concrete-filled-steel-tube columns by circular steel jackets. Thin-Walled Struct., 97, 11-21. DOI: https://doi.org/10.1016/j.tws.2015.09.002
  23. Lai, M. H., & Ho, J. C. M. (2015). Effect of continuous spirals on uni-axial strength and ductility of CFST columns. J. Constr. Steel Res., 104, 235-249. DOI: https://doi.org/10.1016/j.jcsr.2014.10.007
  24. Li, S., Liu, F., Chan, T.-M., Yang, H., & Young, B. (2025). Novel concrete-filled steel square tubular columns stiffened with semi-circles: Concept and behaviour. Thin-Walled Structures, 212, 113188. DOI: https://doi.org/10.1016/j.tws.2025.113188
  25. Lin, C., & Zhou, J. (2023). Axial compressive behaviour of circular composite columns with external confinement. J. of Build. Eng., 77, 107516. DOI: https://doi.org/10.1016/j.jobe.2023.107516
  26. Lyu, F., Ding, F., Xu, Q., & Sun, H. (2024). Refined finite element modelling of circular CFST bridge piers subjected to the seismic load. Compt. Concrete, 33(6), 643-658.
  27. Midhin, A. K., Nabilah, A. B., Nazir, N. A. M., & Safiee, N. A. (2020). Bond behaviour in rubberised concrete-filled circular steel tubes. Int. J. Struct. Eng., 10(4), 293-306. DOI: https://doi.org/10.1504/IJSTRUCTE.2020.109850
  28. Naghipour, M., Khalili, A., Hasani, S. M. R., & Nematzadeh, M. (2022). Experimental investigation of natural bond behavior in circular CFTs. Steel Compos. Struct., 42(2), 191-207.
  29. Nematzadeh, M., & Fazli, S. (2020). Effect of axial loading conditions and confinement type on concrete-steel composite behavior. Compt. Concrete, 25(2), 95-109.
  30. Petrus, C., Hamid, H. A., Ibrahim, A., & Parke, G. (2010). Experimental behaviour of concrete-filled thin-walled steel tubes with tab stiffeners. J. Constr. Steel Res., 66(7), 915-922. DOI: https://doi.org/10.1016/j.jcsr.2010.02.006
  31. Prabhu, G. G., & Sundarraja, M. C. (2013). Behaviour of concrete-filled steel tubular (CFST) short columns externally reinforced using CFRP strips composite. Constr. Build. Mater., 47, 1362-1371. DOI: https://doi.org/10.1016/j.conbuildmat.2013.06.038
  32. Samani, A. K., & Attard, M. M. (2012). A stress-strain model for uniaxial and confined concrete under compression. Eng. Struct., 41, 335-349. DOI: https://doi.org/10.1016/j.engstruct.2012.03.027
  33. Schneider, S. P. (1998). Axially loaded concrete-filled steel tubes. J. Struct. Eng., 124(10), 1125-1138. DOI: https://doi.org/10.1061/(ASCE)0733-9445(1998)124:10(1125)
  34. Tao, Z., Han, L. H., & Wang, D. Y. (2007). Experimental behaviour of concrete-filled stiffened thin-walled steel tubular columns. Thin-Walled Struct., 45(5), 517-527. DOI: https://doi.org/10.1016/j.tws.2007.04.003
  35. Tao, Z., Han, L. H., & Wang, D. Y. (2008). Strength and ductility of stiffened thin-walled hollow steel structural stub columns filled with concrete. Thin-Walled Struct., 46(10), 1113-1128. DOI: https://doi.org/10.1016/j.tws.2008.01.007
  36. Tao, Z., Han, L. H., & Wang, Z. B. (2005). Experimental behaviour of stiffened concrete-filled thin-walled hollow steel structural (HSS) stub columns. J. Constr. Steel Res., 61(7), 962-983. DOI: https://doi.org/10.1016/j.jcsr.2004.12.003
  37. Tao, Z., Song, T. Y., Uy, B., & Han, L. H. (2016). Bond behavior in concrete-filled steel tubes. J. Constr. Steel Res., 120, 81-93. DOI: https://doi.org/10.1016/j.jcsr.2015.12.030
  38. Tao, Z., Uy, B., Han, L. H., & Wang, Z. B. (2009). Analysis and design of concrete-filled stiffened thin-walled steel tubular columns under axial compression. Thin-Walled Struct., 47(12), 1544-1556. DOI: https://doi.org/10.1016/j.tws.2009.05.006
  39. Tao, Z., Wang, Z.-B., & Yu, Q. (2013). Finite element modelling of concrete-filled steel stub columns under axial compression. J. of Constr. Steel Res., 89, 121-131. DOI: https://doi.org/10.1016/j.jcsr.2013.07.001
  40. Thomas, J., & Sandeep, T. N. (2018) Experimental study on circular CFST short columns with intermittently welded stiffeners. Steel Compos. Struct., 29 (5), 659-667.
  41. Thomas, J., & Sandeep, T. N. (2020) Capacity of short circular CFST columns with inner vertical plates welded intermittently. J. Constr. Steel Res., 165, 105840. DOI: https://doi.org/10.1016/j.jcsr.2019.105840
  42. Winti, A. C., Abdullah, A. A., Abdul Karim, A. R., Kueh, A. B. H., & Bronny, B. G. (2026). Axial compressive behavior of square CFST short columns with steel plate reinforcement. Asian Journal of Civil Engineering, 27, 3099-3122. DOI: https://doi.org/10.1007/s42107-026-01658-y
  43. Zhu, B., Li, X., & Yang, D. (2026). Axial compression behaviour of square concrete-filled steel tube columns with stiffeners and multi-spiral stirrups. Structures, 85, 111198. DOI: https://doi.org/10.1016/j.istruc.2026.111198