Earthquakes and Structures

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Demand response modification factor for the investigation of inelastic response of base isolated structures

  • Received : 2012.09.10
  • Accepted : 2013.02.28
  • Published : 2013.07.25
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Abstract

In this study, the effect of flexibility of superstructures and nonlinear characteristics of LRB (Lead Rubber Bearing) isolator on inelastic response of base isolated structures is investigated. To demonstrate the intensity of damage in superstructures, demand response modification factor without the consideration of damping reduction factor, demand RI, is used and the N2 method is applied to compute this factor. To evaluate the influence of superstructure flexibility on inelastic response of base isolated structures, different steel intermediate moment resisting frames with different heights have been investigated. In lead rubber bearing, the rubber provides flexibility and the lead is the source of damping; variations of aforementioned characteristics are also investigated on inelastic response of superstructures. It is observed that an increase in height of superstructure leads to higher value of demand RI till 4-story frame but afterward this factor remains constant; in other words, an increase in height until 4-story frame causes more damage in the superstructure but after that superstructure's damage is equal to the 4-story frame's. The results demonstrate that the low value of second stiffness (rubber stiffness in LRBs) tends to show a significant decrease in demand RI. Increase in value of characteristic strength (yield strength of the lead in LRBs) leads to decrease in the demand RI.

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References

  1. ATC-40 (1996), Seismic evaluation and retrofit of concrete buildings, Applied technology council, Vol. 1 California, Redwood City.
  2. AISC Standard 341-05 (2005), Seismic provisions for structural steel buildings, Chicago, IL.
  3. ASCE/SEI Standard 7-05 (2005), Minimum design loads for buildings and other structures, American society of civil engineers, Reston, VA.
  4. Cardone, D., Dolce, M. and Rivelli, M. (2009), "Evaluation of reduction factors for high-damping design response spectra", Bull. Earthq. Eng., 7(1), 273-291. https://doi.org/10.1007/s10518-008-9097-y
  5. Ceccoli, C., Mazzotti, C., and Savoia, M. (1999), "Non-linear seismic analysis of base-isolated RC frame structures", Earthq. Eng. Struct. D., 28(6), 633-653. https://doi.org/10.1002/(SICI)1096-9845(199906)28:6<633::AID-EQE832>3.0.CO;2-3
  6. Cheng, Y.F., Jiang, H. and Lou, K. (2008), Smart structures: innovative systems for seismic response control, CRC Press, Taylor &Francis Group.
  7. EC8 (2004), Eurocode 8: Design of structures for earthquake resistance, Proceedings of European Committee For Standardisation, Brussels, Belgium.
  8. Erduran, E., Dao, N.D. and Ryan, K.L. (2010), "Comparative response assessment of minimally compliant low-rise conventional and base-isolated steel frames", Earthq. Eng. Struct. D., 40(10), 1123-1141.
  9. ETABS2000 (2009), Computers and Structures Inc (CSI), California, Berkeley.
  10. Fajfar, P. (1999), "Capacity spectrum method based on inelastic demand spectra", Earthq. Eng. Struct. D., 28(9), 979-993. https://doi.org/10.1002/(SICI)1096-9845(199909)28:9<979::AID-EQE850>3.0.CO;2-1
  11. Fajfar, P. (2000), "A nonlinaer analysis method for performance based seismic design", Earthq. Spectra, 16(3), 573-592. https://doi.org/10.1193/1.1586128
  12. FEMA-273 (1997), NEHRP Guidelines for the seismic rehabilitation of buildings: building seismic saftey council for the federal emergency management agency, Washington, DC.
  13. FEMA-356 (2000), Prestandard and commentary for the seimsic rehabilitation of buildings.
  14. FEMA-450 (2003), NEHRP recommended provisions for seismic regulations for new buildings and other structure Part 1 &Part 2.
  15. FEMA-451 (2006), NEHRP recommended provisions : design examples.
  16. Hino, J., Yoshitomi, S., Tsuji, M. and Takewaki, I. (2008), "Bound of aspect ratio of base-isolated buildings considering nonlinear tensile behavior of rubber bearing", Struct. Eng. Mech., 30(3), 351-368. https://doi.org/10.12989/sem.2008.30.3.351
  17. Karavasilis, T.L., Nikitas, B. and Beskos, D.E. (2007), "Behavior factor for performance-based seismic design of plane steel moment resisting frames", J. Earthq. Eng., 11(4), 531-559. https://doi.org/10.1080/13632460601031284
  18. Kelly, J. (1997), Earthquake-resistant design with rubber, Springer.
  19. Kilar, V., and Koren, D. (2008), "Usage of simplified N2 method for analysis of base-isolated structures", Proceedings of the 14th World Conference On Earthquake Engineering, Beijing, China.
  20. Kilar, V. and Koren, D. (2010), "Simplified inelastic seismic analysis of base-isolated structures using the N2 method", Earthq. Eng. Struct. D., 39(9), 967-989.
  21. Kulkarni, J.A. and Jangid, R.S. (2002), "Rigid body response of base-isolated structures", J. Struct. Control, 9(3), 171-188. https://doi.org/10.1002/stc.11
  22. Maheri, M., and Akbari, R. (2003), "Seismic behavior factor, R, for steel X-braced and knee-braced RC buildings", Eng. Struct., 25(12), 1505-1513. https://doi.org/10.1016/S0141-0296(03)00117-2
  23. Matasagar, V. and Jangid, R.S. (2004), "Influence of isolator characteristics on the response of base-isolated structures", Eng. Struct., 26(12), 1735-1749. https://doi.org/10.1016/j.engstruct.2004.06.011
  24. MATLAB2009a (2009), MathWorks, Inc, The Language of Technical Computing.
  25. Mwafy, A.M. and Elanshai, A.S. (2001), "Calibration of force reduction factors of RC buildings", J. Earthq. Eng., 6(2), 239-273.
  26. Mwafy, A. and Elanshai, A. (2001), "Static pushover versus dynamic collapse analysis of RC buildings", Eng. Struct., 23(5), 407-424. https://doi.org/10.1016/S0141-0296(00)00068-7
  27. Naeim, F. and Kelly, J. (1999), Design of seismic isolated structures: from theory to practice, John Wiley.
  28. Ordonez, D., Foti, D.,and Bozzo, L. (2003), "Comparative study of the inelastic structural response of base isolated buildings", Earthq. Eng. Struct. D., 32(1), 151-164. https://doi.org/10.1002/eqe.224
  29. Palazzo, B. and Petti, L. (1996), Reduction factors for base isolated structures, Comput. Struct., 60(6), 945-956. https://doi.org/10.1016/0045-7949(95)00428-9
  30. Providakis, C.P. (2008), "Pushover analysis of base-isolated steel-concrete structures under near-fault excitations", Soil Dyn. Earthq. Eng., 28(4), 293-304. https://doi.org/10.1016/j.soildyn.2007.06.012
  31. Ramirez, O.M., Constantinou, M.C., Whittaker, A.S., Kircher, C.A. and Chrysostomou, C.Z. (2002), "Elastic and inelastic seismic response of buildings with damping systems earthquake spectra", Earthq. Spectra , 18(3), 531-547. https://doi.org/10.1193/1.1509762
  32. Ryan, K.L. and Chopra, A.K. (2004), "Estimation of seismic demands on isolators based on nonlinear analysis", J. Struct. Eng. - ASCE, 130(3), 392-402. https://doi.org/10.1061/(ASCE)0733-9445(2004)130:3(392)
  33. Sayani, P.J., Erduran, E. and Ryan, K.L. (2010), "Comparative response assessment of minimally compliant low-rise base-isolated and conventional steel moment resisting frame buildings", J. Struct. Eng- ASCE, 137(10), 1118-1131.
  34. Sayani, P.J. and Ryan, K.L. (2009), "Comparative evaluation of fixed-base and base-isolated buildings using a comprehensive response index", J. Struct. Eng. - ASCE, 135(6), 698-707. https://doi.org/10.1061/(ASCE)0733-9445(2009)135:6(698)
  35. Sayani, P.J. and Ryan, K.L. (2009), "Evaluation of approaches to characterize seismic isolation for design", J. Earthq. Eng., 13(6), 835-851. https://doi.org/10.1080/13632460802715057
  36. Seneviratna, G. and Krawinkler, H. (1998), "Pros and cons of a pushover analysis of seismic performance evaluation", Eng. Struct., 20(4-6), 452-464. https://doi.org/10.1016/S0141-0296(97)00092-8
  37. Sharma, J. and Jangid, R.S. (2009), "Behaviour of base-islolated structures with high intial isolator stiffness", J. Eng. Appl. Sci., 5(3), 199-204.
  38. Tena-Colunga (2008), "The new guidelines for the seismic design of base isolated structures in Mexico", Proceedings of the 14th World Conference On Earthquake Engineering, Beijing, China.
  39. Uang, C.M. (1991), "Comparison of seismic force reduction factors used in U.S.A and Japan", Earthq. Eng. Struct. D., 20(4), 389-397. https://doi.org/10.1002/eqe.4290200407
  40. Uang, C.M. (1991), "Establishing R (or RW) and Cd factors for building seismic provisions", J. Struct. Eng., 117(1), 19-28. https://doi.org/10.1061/(ASCE)0733-9445(1991)117:1(19)
  41. Uinform Building Code (UBC) (1997), International conference of building officials, California, Whittier.
  42. Vidic, T., Fajfar, P. and Fischinger, M. (1994), "Consistent inelastic design spectra: strength and displacement", Earthq. Eng. Struct. D., 23(5), 507-521. https://doi.org/10.1002/eqe.4290230504

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