DOI QR코드

DOI QR Code

Experimental investigation of damaged RC joints retrofitted by stiffened angles and bars

  • 투고 : 2021.02.05
  • 심사 : 2021.05.01
  • 발행 : 2021.05.25

초록

Experimental studies reveal that weakness in joint core leads to the formation of a shear hinge in this area, loss of load carrying capacity in the both regions of cyclic curve and decrease of ductility. Generally, the recent mentioned results are related to the previous studies, in which the effect of slabs and lateral beams (2D joints) have been neglected. However, these effects can lead to different responses in real joints compared to ideal 2D joints, in the term of changes in capacity and demand. Consequently, in this study the effect of slab and lateral beam has been considered (3D joints). Four 3D external joints with a scale of 1/2 are made in the laboratory. Specimens include two control joints and two damaged joints retrofitted by stiffened angles and post-tensioned bars. The results show that the use of retrofit method for damaged joints results in the formation of a flexural plastic hinge in the beam and shift of the shear hinge out of the joint core. Furthermore, the effect of slab and lateral beam in the bare non-seismic joint may lead to the increase of the ductility, compared to the similar 2D joints in previous studies.

키워드

참고문헌

  1. ACI 318 (2014), Building Code Requirements for Structural Concrete 318M-14. American Concrete Institute ACI Committee: Farmington Hills, MI, U.S.A.
  2. ACI 318 (2019), Building Code Requirements for Structural Concrete and Commentary 318R-19. American Concrete Institute ACI Committee: Farmington Hills, MI, U.S.A.
  3. Adibi, M., Marefat, M.S., Esmaeily, A., Arani, K.K. and Esmaeily, A. (2017), "Seismic retrofit of external concrete beam-column joints reinforced by plain bars using steel angles prestressed by cross ties", Eng. Struct., 148, 813-828. https://doi.org/10.1016/j.engstruct.2017.07.014.
  4. Adibi, M., Shafaei, J. and Aliakbari, F. (2020), "Experimental evaluation of external beam-column joints reinforced by deformed and plain bar", Earthq. Struct., 18(1), 113-127. https://doi.org/10.12989/eas.2020.18.1.113.
  5. AISC 360 (2016), Specification for Structural Steel Buildings, American Institute of Steel Construction, Chicago, Illinois, U.S.A.
  6. Al-Osta, M.A., Khan, M.I., Bahraq, A.A. and Xu, S.Y. (2020), "Application of ultra-high performance fiber reinforced concrete for retrofitting the damaged exterior reinforced concrete beam-column joints", Earthq. Struct., 19(5), 361-377. https://doi.org/10.12989/eas.2020.19.5.361.
  7. Al-Salloum, Y.A., Siddiqui, N.A., Al-Salloum, Y.A., Siddiqui, N.A., Elsanadedy, H.M., Abadel, A.A. and Aqel, M.A. (2011), "Textile-reinforced mortar versus FRP as strengthening material for seismically deficient RC beam-column joints", J. Compos. Construct., 15(6), 920-933. https://doi.org/10.1061/(ASCE)CC.1943-5614.0000222.
  8. Altoontash, A. (2004), "Simulation and damage models for performance assessment of reinforced concrete beam-column joints", Ph.D. thesis, Dept. of Civil and Environmental Engineering, Stanford Univ.
  9. Arzeytoon, A., Hosseini, A. and Goudarzi, A. (2014), "Seismic rehabilitation of exterior RC beam-column joints using steel plates, angles, and posttensioning rods", J. Perform. Construct. Facilities 30(1), 04014200. https://doi.org/10.1061/(ASCE)CF.1943-5509.0000721.
  10. Bedirhanoglu, I., Ilki, A., Incecik, O. and Kumbasar, N. (2008), Retrofit of concrete panels with prefabricated HPFRCC plates. 14th World Conference on Earthquake Engineering. Beijing, China, October.
  11. Beschi, C., Riva, P., Metelli, G. and Meda, A. (2015), "HPFRC jacketing of non seismically detailed RC corner joints", J. Earthq. Eng. 19(1), 25-47. https://doi.org/10.1080/13632469.2014.948646.
  12. Bindhu, K., Mohana, N. and Sivakumar, S. (2014), "New reinforcement detailing for concrete jacketing of nonductile exterior beam-column joints", J. Perform. Construct. Facilities 30(1), 04014192. https://doi.org/10.1061/(ASCE)CF.1943-5509.0000700.
  13. Campione, G., Cavaleri, L. and Papia, M. (2015), "Flexural response of external RC beam-column joints externally strengthened with steel cages", Eng. Struct., 104, 51-64. https://doi.org/10.1016/j.engstruct.2015.09.009.
  14. Cosenza, E., Manfredi, G. and Ramasco, R. (1993), "The use of damage functionals in earthquake engineering: a comparison between different methods", Earthq. Eng. Struct. Dyn., 22(10), 855-868. https://doi.org/10.1002/eqe.4290221003.
  15. Dang, C.T. and Dinh, N.H. (2017), "Experimental study on structural performance of RC exterior beam-column joints retrofitted by steel jacketing and haunch element under cyclic loading simulating earthquake excitation", Advan. Civil Eng., 2017, https://doi.org/10.1155/2017/9263460.
  16. Del Vecchio, C., Di Ludovico, M., Balsamo, A. and Prota, A. (2018), "Seismic retrofit of real beam-column joints using fiberreinforced cement composites", J. Struct. Eng 144(5), 04018026. https://doi.org/10.1061/(ASCE)ST.1943-541X.0001999.
  17. Ghomia, S.K. and El-Salakawy, E. (2020), "Effect of geometrical configuration on seismic behavior of GFRP-RC beam-column joints", Advan. Concrete Construct. 9(3), 313-326. https://doi.org/10.12989/acc.2020.9.3.313.
  18. https://doi.org/10.1016/j.istruc.2021.02.032.
  19. https://doi.org/10.1061/(ASCE)0733-9445(1985)111:4(722).
  20. Kakavetsis, D.J., David, K.N. and Karayannis, C.G. (2011), "Effectiveness of some conventional seismic retrofitting techniques for bare and infilled R/C frames", Struct. Eng. Mech., 39(4), 499-520. http://dx.doi.org/10.12989/sem.2011.39.4.499.
  21. Kalogeropoulos, G.I. and Tsonos, A.G. (2014), "Effectiveness of R/C jacketing of substandard R/C columns with short lap splices", Struct. Monit. Maintenance, 1(3), 273-292. http://dx.doi.org/10.12989/smm.2014.1.3.273.
  22. Kanchana Devi, A.K., Karusala, R., Tripathi, M. and Sasmal, S. (2018), "Novel non-invasive seismic upgradation strategies for gravity load designed exterior beam-column joints", Archiv. Civil Mech. Eng., 18(2), 479-489. https://doi.org/10.1016/j.acme.2017.08.005.
  23. Karayannis, C.G. and Golias, E. (2018), "Full scale tests of RC joints with minor to moderate seismic damage repaired using CFRP sheets", Earthq. Struct., 15(6), 617-627. https://doi.org/10.12989/eas.2018.15.6.617.
  24. Karayannis, C.G. and Golias, E. (2021), "Strengthening of deficient RC joints with diagonally placed external C-FRP ropes", Earthq. Struct., 20(1), 123-132. http://dx.doi.org/10.12989/eas.2021.20.1.123
  25. Khan, M.I., Al-Osta, M.A., Ahmad, S. and Rahman, M.K. (2018), "Seismic behavior of beam-column joints strengthened with ultra-high performance fiber reinforced concrete", Compos. Struct., 200, 103-119. https://doi.org/10.1016/j.compstruct.2018.05.080.
  26. Khodaei, M., Saghafi, M.H. and Golafshar, A. (2021), "Seismic retrofit of exterior beam-column joints using steel angles connected by PT bars", Eng. Struct., 236, 112111. https://doi.org/10.1016/j.engstruct.2021.112111.
  27. Maddah, A., Golafshar, A. and Saghafi, M.H. (2020), "3D RC beam-column joints retrofitted by joint enlargement using steel angles and post-tensioned bolts", Eng. Struct., 220, 110975. https://doi.org/10.1016/j.engstruct.2020.110975.
  28. Marthong, C. (2019), "Behavior of repaired RAC beam-column joints using steel welded wire mesh jacketed with cement mortar", Advan. Concrete Construct., 8(2), 91-100. http://dx.doi.org/10.12989/acc.2019.8.2.091.
  29. Nouri, A., Saghafi, M.H. and Golafshar, A. (2019), "Evaluation of beam-column joints made of HPFRCC composites to reduce transverse reinforcements", Eng. Struct., 201, 109826. https://doi.org/10.1016/j.engstruct.2019.109826.
  30. Oinam, R.M., Kumar, P.C. and Sahoo, D.R. (2019), "Cyclic performance of steel fiber-reinforced concrete exterior beamcolumn joints", Earthq. Struct., 16(5), 533-546. https://doi.org/10.12989/eas.2019.16.5.533.
  31. Park, R. (1986), "Ductile design approach for reinforced concrete frames", Earthq. Spectra 2(3), 565-619. https://doi.org/10.1193/1.1585398.
  32. Park, Y. J. and Ang, A.H.S. (1985), "Mechanistic seismic damage model for reinforced concrete", J. Struct. Eng., 111(4), 722-739. https://doi.org/10.1061/(ASCE)0733-9445(1985)111:4(722)
  33. Raj, S.D., Ganesan, N. and Abraham, R. (2020), "Role of fibers on the performance of geopolymer concrete exterior beam column joints", Advan. Concrete Construct., 9(2), 115-123. https://doi.org/10.12989/acc.2020.9.2.115.
  34. Saghafi, M.H., Golafshar, A., Zareian, M.S. and Kashani, M. (2020), "The effect of high-performance fiber-reinforced cementitious composites on the lateral behavior of reinforced concrete frames without seismic details", Struct., 26, 801-813. https://doi.org/10.1016/j.istruc.2020.05.012.
  35. Saghafi, M.H., Golafshar, A., Zareian, M.S. and Mehri, A.H. (2021), "Application of HPFRCC in beam-column joints to reduce transverse reinforcements", Struct., 31, 805-814. https://doi.org/10.1016/j.istruc.2021.02.032
  36. Sasmal, S. and Voggu, S. (2018), "Strut-relieved single steel haunch bracing system for mitigating seismic damage of gravity load designed structures", J. Struct. Eng., 144(10), 04018167. https://doi.org/10.1061/(ASCE)ST.1943-541X.0002167.
  37. Shaaban, I.G. and Seoud, O.A. (2018), "Experimental behavior of full-scale exterior beam-column space joints retrofitted by ferrocement layers under cyclic loading", Case Studies Construct. Mater., 8, 61-78. https://doi.org/10.1016/j.cscm.2017.11.002.
  38. Shafaei, J., Hosseini, A. and Marefat, M.S. (2014), "Seismic retrofit of external RC beam-column joints by joint enlargement using prestressed steel angles", Eng. Struct., 81, 265-288. https://doi.org/10.1016/j.engstruct.2014.10.006.
  39. Shafaei, J., Hosseini, A., Marefat, M.S. and Ingham, J.M. (2017), "Rehabilitation of earthquake damaged external RC beam- column joints by joint enlargement using prestressed steel angles", Earthq. Eng. Struct. Dyn., 46(2), 291-316. https://doi.org/10.1002/eqe.2794.
  40. Sharma, R. and Bansal, P.P. (2019), "Behavior of RC exterior beam column joint retrofitted using UHP-HFRC", Construct. Build. Mater., 195, 376-389. https://doi.org/10.1016/j.conbuildmat.2018.11.052.
  41. Torabi, A. and Maheri, M.R. (2017), "Seismic repair and retrofit of RC beam-column joints using stiffened steel plates", Iranian J. Sci. Technol. Transaction Civil Eng., 41(1), 13-26. https://doi.org/10.1007/s40996-016-0027-y.
  42. Tsonos, A.-D. G. (2010). "Performance enhancement of R/C building columns and beam-column joints through shotcrete jacketing." Engineering Structures 32(3): 726-740. https://doi.org/10.1016/j.engstruct.2009.12.001.
  43. Tsonos, A.G. (2002), "Seismic repair of reinforced concrete beam-column subassemblages of modern structures by epoxy injection technique", Struct. Eng. Mech., 14(5), 543-563. http://dx.doi.org/10.12989/sem.2002.14.5.543.
  44. Tsonos, A.G. (2014), "An innovative solution for strengthening of old R/C structures and for improving the FRP strengthening method", Struct. Monit. Maintenance, 1(3), 323-328. http://dx.doi.org/10.12989/smm.2014.1.3.323.
  45. Tsonos, A.G. (2019), "Model for the evaluation of the beam-column joint ultimate strength-a more simplified version", Earthq. Struct., 16(2), 141-148. http://dx.doi.org/10.12989/eas.2019.16.2.141.
  46. Wang, Y.C. (2012), "Reinforced concrete jacketing for seismic upgrading of RC frames with poor reinforcing details in beam-column joints", The Twenty-second International Offshore and Polar Engineering Conference, International Society of Offshore and Polar Engineers. Rhodes, Greece, June.
  47. Yang, Y., Chen, Y., Chen, Z., Wang, N. and Yu, Y. (2018), "Experimental study on seismic behavior of RC beam-column joints retrofitted using prestressed steel strips", Earthq. Struct., 15(5), 499-511. https://doi.org/10.12989/eas.2018.15.5.499.
  48. Zabihi, A., Tsang, H.H., Gad, E.F. and Wilson, J.L. (2018), "Seismic retrofit of exterior RC beam-column joint using diagonal haunch", Eng. Struct., 174, 753-767. https://doi.org/10.1016/j.engstruct.2018.07.100.