Comparative performance of seismically deficient exterior beam-column sub-assemblages of different design evolutions: A closer perspective

  • Kanchana Devi, A. ;
  • Ramanjaneyulu, K.
  • Received : 2017.05.18
  • Accepted : 2017.08.05
  • Published : 2017.08.25


In the present study, exterior beam column sub-assemblages are designed in accordance with the codal stipulations prevailed at different times prior to the introduction of modern seismic provisions, viz., i) Gravity load designed with straight bar anchorage (SP1), ii) Gravity load designed with compression anchorage (SP1-D), iii) designed for seismic load but not detailed for ductility (SP2), and iv) designed for seismic load and detailed for ductility (SP3). Comparative seismic performance of these exterior beam-column sub-assemblages are evaluated through experimental investigations carried out under repeated reverse cyclic loading. Seismic performance parameters like load-displacement hysteresis behavior, energy dissipation, strength and stiffness degradation, and joint shear deformation of the specimens are evaluated. It is found from the experimental studies that with the evolution of the design methods, from gravity load designed to non-ductile and then to ductile detailed specimens, a marked improvement in damage resilience is observed. The gravity load designed specimens SP1 and SP1-D respectively dissipated only one-tenth and one-sixth of the energy dissipated by SP3. The specimen SP3 showcased tremendous improvement in the energy dissipation capacity of nearly 2.56 times that of SP2. Irrespective of the level of design and detailing, energy dissipation is finally manifested through the damage in the joint region. The present study underlines the seismic deficiency of beam-column sub-assemblages of different design evolutions and highlights the need for their strengthening/retrofit to make them fit for seismic event.


beam-column sub-assemblage;seismic design;ductile detailing;energy dissipation;strength degradation;shear deformation


  1. ACI 318M (2011), Building Code Requirements for Structural Concrete and Commentary, Farmington Hills, MI, USA.
  2. Aycardi, L.E., Mander, J.B. and Reinhorn, A.M. (1994), "Seismic resistance of reinforced concrete frame structures designed only for gravity loads: Experimental performance of subassemblages", ACI Struct. J., 91(5), 552-563.
  3. Bakir, P.G. (2003), "Seismic resistance and mechanical behaviour of exterior beam-column joints with crossed inclined bars", Struct. Eng. Mech., 16(4), 493-517.
  4. Bindhu, K.R., Jaya, K.P. and Manicka Selvam, V.K. (2008), "Seismic resistance of exterior beam-column joints with non-conventional confinement reinforcement detailing", Struct. Eng. Mech., 30(6), 733-761.
  5. Blakeley, R.W.G., Megget, L.M. and Priestley, M.J.N. (1975), "Seismic performance of two full size reinforced concrete beam-column joint units", Bull. NZ. Nat'l Soc. Earthq. Eng., 8(1), 38-69.
  6. Bracci, J.M., Reinhorn, A.M. and Mander, J.B. (1995), "Seismic resistance of reinforced concrete frame structures designed for gravity loads: performance of structural system", ACI Struct. J., 92(5), 597-609.
  7. Calvi, G.M., Magenes, G. and Pampanin, S. (2002), "Experimental test on a three storey RC frame designed for gravity only", 12th European Conference on Earthquake Engineering, September, London.
  8. Chun, S.C. (2014), "Effects of joint aspect ratio on required transverse reinforcement of exterior joints subjected to cyclic loading", Earthq. Struct., 7(5), 705-718.
  9. Dhakal, R.P., Pan, T.C., Irawan, P., Tsai, K.C., Lin, K.C. and Chen, C.H. (2005), "Experimental study on the dynamic response of gravity-designed reinforced concrete connections", Eng. Struct., 27(1), 75-87.
  10. Ehsani, M.R. and Wight, J.K. (1985), "Exterior reinforced concrete beam to column connections subjected to Earthquake - type loading", ACI Struct. J., 82(4), 492-499.
  11. El-Attar, A.G., White, R.N. and Gergely, P. (1997), "Behaviour of gravity load designed reinforced concrete buildings subjected to earthquakes", ACI Struct. J., 94(2), 133-145.
  12. EC8 (2004), Design of structures for earthquake resistance - Part 1: General rules, seismic actions and rules for buildings, European committee for standardization, Brussels, Belgium.
  13. FEMA 273 (1997), "Guidelines for the seismic rehabilitation of buildings", Federal Emergency Management Agency, Washington, D.C., USA.
  14. IS 1893(2002), Criteria for earthquake resistant design of structures (Part 1): General provisions and buildings, Bureau of Indian Standards, New Delhi, India.
  15. IS 456(2000), Code of practice for plain and reinforced concrete (Fourth revision), Bureau of Indian Standards, New Delhi, India.
  16. IS 13920 (1993), Ductility detailing of reinforced concrete structures subjected to seismic forces, Bureau of Indian Standards, New Delhi, India.
  17. Masi, A., Santarsiero, G., Lignola, G.P. and Verderame, G.M. (2013), "Study of the seismic behaviour of external RC beam-column joints through experimental tests and numerical simulations", Eng. Struct., 52, 207-219.
  18. Marthong, C., Deb, S.K. and Anjan Dutta (2016), "Experimental fragility functions for exterior deficient RC beam-column connections before and after rehabilitation", Earthq. Struct., 10(6), 1291-1314.
  19. Megget, L.M. and Park, R. (1971), "Reinforced concrete exterior beam-column joints under seismic loading", NZ. Eng., 26(11), 341-353.
  20. Murty, C.V.R, Rai, D.C., Bajpai, K.K. and Jain S.K. (2003), "Effectiveness of reinforcement details in exterior reinforced concrete beam-column joints for earthquake resistance", ACI Struct. J., 100(2), 149-156.
  21. NZS 3101(2006), Concrete Structures Standard Part 1 -The Design of Concrete Structures, Standards New Zealand, Wellington, New Zealand.
  22. Pantelides, C.P., Hansen, J., Nadauld, J. and Reaveley, L.D. (2002), "Assessment of reinforced concrete building exterior joints with substandard details", PEER Report 18, University of California, Berkeley.
  23. Park, R. and Paulay, T. (1973), "Behaviour of reinforced concrete external beam column joints under cyclic loading", Proceedings of Fifth World Conference on Earthquake Engineering, 1, 772-781.
  24. Park, R. and Yeoh Sik Keong (1979), "Tests on structural concrete beam-column joints with intermediate column bars", Bull. NZ. Nat'l Soc. Earthq. Eng., 12(3), 2361-2376.
  25. Paulay, T. and Scarpas, A. (1981), "The behaviour of exterior beam-column joints", Bull. NZ. Nat'l Soc. Earthq. Eng., 14(3), 131-144.
  26. Paulay, T., Park, R. and Priestley, M.J.N. (1978), "Reinforced concrete beam-column joints under seismic actions", Proceedings Journal of the American Concrete Institute, 75(11), 585-593.
  27. Rajagopal, S. and Prabavathy, S. (2013), "Study of exterior beam-column joint with different joint core and anchorage details under reversal loading", Struct. Eng. Mech., 46(6), 809-825.
  28. Supaviriyakit, T. and Pimanmas, A. (2008), "Comparative performance of sub-standard interior reinforced concrete beam-column connection with various joint reinforcing details", Mater. Struct., 41(3), 543-557.
  29. Somma, G., Pieretto, A., Rossetti, T. and Grant, D.N. (2015), "R.C. beam to column connection failure assessment and limit state design", Mater. Struct., 48(4), 1215-1231.
  30. Tsonos, A.G. (2007), "Cyclic load behavior of reinforced concrete beam-column sub-assemblages of modern structures", ACI Struct. J., 104(4), 468-478.
  31. Yavari, S., Elwood, K.J., Wu, C.L., Lin, S.H., Hwang, S.J. and Moehle, J.P. (2013), "Shaking table tests on reinforced concrete frames without seismic detailing", ACI Struct. J., 110(6), 1001-1012.