Structural Engineering and Mechanics

  • 제77권6호
  • /
  • Pages.705-720
  • /
  • 2021
  • /
  • 1225-4568(pISSN)
  • /
  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Axial strengthening of RC columns by direct fastening of steel plates

  • Shan, Z.W. (Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education, Southeast University) ;
  • Su, R.K.L. (Department of Civil Engineering, The University of Hong Kong)
  • 투고 : 2019.04.24
  • 심사 : 2021.01.09
  • 발행 : 2021.03.25
⟨ 이전 논문 다음 논문 ⟩

초록

Reinforced concrete (RC) columns are the primary type of vertical support used in building structures that sustain vertical loads. However, their strength may be insufficient due to fire, earthquake or volatile environments. The load demand may be increased due to new functional usages of the structure. The deformability of concrete columns can be greatly reduced under high axial load conditions. In response, a novel steel encasement that distinguishes from the traditional steel jacketing that is assembled by welding or bolt is developed. This novel strengthening method features easy installation and quick strengthening because direct fastening is used to connect the four steel plates surrounding the column. This new connection method is usually used to quickly and stably connect two steel components by driving high strength fastener into the steel components. The connections together with the steel plates behave like transverse reinforcement, which can provide passive confinement to the concrete. The confined column along with the steel plates resist the axial load. By this way, the axial load capacity and deformability of the column can be enhanced. Eight columns are tested to examine the reliability and effectiveness of the proposed method. The effects of the vertical spacing between adjacent connections, thickness of the steel plate and number of fasteners in each connection are studied to identify the critical parameters which affect the load bearing performance and deformation behavior. Lastly, a theoretical model is proposed for predicting the axial load capacity of the strengthened RC columns.

키워드

참고문헌

  1. Adam, J.M., Ivorra, S., Pallares, F.J., Gimenez, E. and Calderon, P.A. (2009), "Axially loaded RC columns strengthened by steel caging: Finite element modeling", Constr. Build. Mater., 23(6), 2265-2276. https://doi.org/10.1016/j.conbuildmat.2008.11.014.
  2. ASCE 41-13 (2014), Seismic Evaluation and Retrofit of Existing Buildings, American Society of Civil Engineers, Reston, Virginia, USA.
  3. Attard, M.M. and Setunge, S. (1996), "Stress-strain relationship of confined and unconfined concrete", ACI Mater. J., 93(5), 432-442.
  4. Campione, G. (2012), "Strength and ductility of RC columns strengthened with steel angles and battens", Constr. Build. Mater., 35, 800-807. https://doi.org/10.1016/j.conbuildmat.2012.04.090.
  5. Campione, G., Cavaleri, L., Di Trapani, F. and Ferrotto, M.F. (2017), "Frictional effects in structural behavior of no-end-connected steel-jacketed RC columns: experimental results and new approaches to model numerical and analytical response", J. Struct. Eng., 143(8), 04017070. https://doi.org/10.1061/(ASCE)ST.1943-541X.0001796.
  6. Campione, G., Cavaleri, L., Ferrotto, M.F., Macaluso, G. and Papia, M. (2016), "Efficiency of stress-strain models of confined concrete with and without steel jacketing to reproduce experimental results", Open Constr. Build. Technol. J., 10(1), 65-86. https://doi.org/ 10.2174/1874836801610010065.
  7. Chen, J., Chan, T.M., Su, R.K.L. and Castro, J.M. (2019), "Experimental assessment of the cyclic behaviour of concrete-filled steel tubular beam-columns with octagonal sections", Eng. Struct., 180, 544-560. https://doi.org/10.1016/j.engstruct.2018.10.078.
  8. Dhakal, R.P. and Maekawa, K. (2002), "Modeling for postyield buckling of reinforcement", J. Struct. Eng., 128(9), 1139-1147. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:9(1139).
  9. Elwood, K.J. and Moehle, J.P. (2005), "Axial capacity model for shear-damaged columns", ACI Struct. J., 102(4), 578-587. https://doi.org/10.14359/14562.
  10. EN ISO 6892-1 (2016), Metallic Materials-Tensile Testing. Part 1: Method of Test at Room Temperature, International Organization for Standardization (ISO), Geneva, Switzerland.
  11. Ferrotto, M.F., Cavaleri, L. and Papia, M. (2018), "Compressive response of substandard steel-jacketed RC columns strengthened under sustained service loads: From the local to the global behavior", Constr. Build. Mater., 179, 500-511. https://doi.org/10.1016/j.conbuildmat.2018.05.247.
  12. Guo, Z.H. and Wang, C.Z. (1991), "Investigation of strength and failure criterion of concrete under multi-axial stresses", Chin. Civil Eng. J., 24(3), 1-14.
  13. He, A., Cai, J., Chen, Q.J., Liu, X., Huang, P. and Tang, X.L. (2018), "Seismic behaviour of steel-jacket retrofitted reinforced concrete columns with recycled aggregate concrete", Constr. Build. Mater., 158, 624-639. https://doi.org/10.1016/j.conbuildmat.2017.10.053.
  14. He, A., Cai, J., Chen, Q.J., Liu, X., Xue, H. and Yu, C. (2017), "Axial compressive behaviour of steel-jacket retrofitted RC columns with recycled aggregate concrete", Constr. Build. Mater., 41, 501-516. https://doi.org/10.1016/j.conbuildmat.2017.03.013.
  15. Hilti Corporation (2018), Direct Fastening Technology Manual.
  16. Jain, S., Chellapandian, M. and Prakash, S.S. (2017), "Emergency repair of severely damaged reinforced concrete column elements under axial compression: An experimental study", Constr. Build. Mater., 155, 751-761. https://doi.org/10.1016/j.conbuildmat.2017.08.127.
  17. Julio, E.S., Branco, F. and Silva, V.D. (2003), "Structural rehabilitation of columns with reinforced concrete jacketing", Prog. Struct. Eng. Mater., 5(1), 29-37. https://doi.org/10.1002/pse.140.
  18. La Mendola, L. and Papia, M. (2002), "General stress-strain model for concrete or masonry response under uniaxial cyclic compression", Struct. Eng. Mech., 14(4), 435-454. https://doi.org/10.12989/sem.2002.14.4.435.
  19. Looi, D.T.W., Su, R.K.L., Cheng, B. and Tsang, H.H. (2017), "Effects of axial load on seismic performance of reinforced concrete walls with short shear span", Eng. Struct., 151, 312-326. https://doi.org/10.1016/j.engstruct.2017.08.030.
  20. Ma, C.K., Apandi, N.M., Sofrie, C.S.Y., Ng, J.H., Lo, W.H., Awang, A.Z. and Omar, W. (2017), "Repair and rehabilitation of concrete structures using confinement: A review", Constr. Build. Mater., 133, 502-515. https://doi.org/10.1016/j.conbuildmat.2016.12.100.
  21. Mahdavi, N., Ahmadi, H.R. and Bayat, M. (2019), "Efficient parameters to predict the nonlinear behavior of FRP retrofitted RC columns", Struct. Eng. Mech., 70(6), 703-710. https://doi.org/10.12989/sem.2019.70.6.703.
  22. Mander, J.B., Priestley, M.J. and Park, R. (1988), "Theoretical stress-strain model for confined concrete", J. Struct. Eng., 114(8), 1804-1826. https://doi.org/10.1061/(ASCE)0733-9445(1988)114:8(1804).
  23. Marthong, C. (2019), "Rehabilitation and strengthening of exterior RC beam column connections using epoxy resin injection and FRP sheet wrapping: Experimental study", Struct. Eng. Mech., 72(6), 723. https://doi.org/10.12989/sem.2019.72.6.723.
  24. Montuori, R. and Piluso, V. (2009), "Reinforced concrete columns strengthened with angles and battens subjected to eccentric load", Eng. Struct., 31(2), 539-550. https://doi.org/10.1016/j.engstruct.2008.10.005.
  25. Moretti, M.L. (2019), "Effectiveness of different confining configurations of FRP jackets for concrete columns", Struct. Eng. Mech., 72(2), 15-28. https://doi.org/10.12989/sem.2019.72.2.155.
  26. Moshiri, N., Hosseini, N.A. and Mostofinejad, D. (2015), "Strengthening of RC columns by longitudinal CFRP sheets: Effect of strengthening technique", Constr. Build. Mater., 79, 318-325. https://doi.org/10.1016/j.conbuildmat.2015.01.040.
  27. Narule, G.N. and Bambole, A.N. (2018), "Axial behavior of CFRP wrapped RC columns of different shapes with constant slenderness ratio", Struct. Eng. Mech., 65(6), 679-687. https://doi.org/10.12989/sem.2018.65.6.679.
  28. Obaidat, Y.T., Abu-Farsakh, G.A. and Ashteyat, A.M. (2019), "Retrofitting of partially damaged reinforced concrete beamcolumn joints using various plate-configurations of CFRP under cyclic loading", Constr. Build. Mater., 198, 313-322. https://doi.org/10.1016/j.conbuildmat.2018.11.267.
  29. Rodriguez, M. and Park, R. (1994), "Seismic load tests on reinforced concrete columns strengthened by jacketing", ACI Struct. J., 91(2), 150-159. https://doi.org/10.14359/4593.
  30. Saatcioglu, M. and Razvi, S.R. (1992), "Strength and ductility of confined concrete", J. Struct. Eng., 118(6), 1590-1607. https://doi.org/10.1061/(ASCE)0733-9445(1992)118:6(1590).
  31. Shan, Z.W. and Su, R.K.L. (2019), "Behavior of shear connectors joined by direct fastening", Eng. Struct., 196, 109321. https://doi.org/10.1016/j.engstruct.2019.109321.
  32. Su, R.K.L and Cheng, B. (2008), "The effect of coarse aggregate size on the stress-strain curves of concrete under uniaxial compression", HKIE Tran., 15(3), 33-39. https://doi.org/10.1080/1023697X.2008.10668122.
  33. Su, R.K.L. and Wang, L. (2012), "Axial strengthening of preloaded rectangular concrete columns by precambered steel plates", Eng. Struct., 38, 42-52. https://doi.org/10.1016/j.engstruct.2012.01.003.
  34. Su, R.K.L. and Wang, L. (2015), "Flexural and axial strengthening of preloaded concrete columns under large eccentric loads by flat and precambered steel plates", Struct. Infrastr. E., 11(8), 1083-101. https://doi.org/10.1080/15732479.2014.936879.
  35. Truong, G.T., Kim, J.C. and Choi, K.K. (2017), "Seismic performance of reinforced concrete columns retrofitted by various methods", Eng. Struct., 134, 217-235. https://doi.org/10.1016/j.engstruct.2016.12.046.
  36. Tunaboyu, O. and Avsar, O. (2017), "Seismic repair of captive-column damage with CFRPs in substandard RC frames", Struct. Eng. Mech., 61(1), 1-13. https://doi.org/10.12989/sem.2017.61.1.001.
  37. Wang, L. and Su, R.K.L. (2012), "Theoretical and experimental study of plate-strengthened concrete columns under eccentric compression loading", J. Struct. Eng., 139(3), 350-9. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000659.
  38. Wang, L. and Su, R.K.L. (2018), "Strengthening of preloaded RC columns by post compressed plates-a review", Struct. Eng. Mech., 65, 477-490. https://doi.org/10.12989/sem.2018.65.4.477.
  39. Zhu, L., Elwood, K.J. and Haukaas, T. (2007), "Classification and seismic safety evaluation of existing reinforced concrete columns", J. Struct. Eng., 133(9), 1316-1330. https://doi.org/10.1061/(ASCE)0733-9445(2007)133:9(1316).