Earthquakes and Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Suspended Columns for Seismic Isolation in Structures (SCSI): A preliminary analytical study

  • Received : 2018.08.17
  • Accepted : 2019.04.10
  • Published : 2019.06.25
⟨ Previous Next ⟩

Abstract

In this paper, a new system of seismic isolation for buildings - called suspended columns - is introduced. In this method, the building columns are placed on the hinged cradle seats instead of direct connection to the foundation. In this system, each of the columns is put on a seat hung from its surrounding area by a number of cables, for which cavities are created inside the foundation around the columns. Inside these cavities, the tensile cables are hung. Because of the flexibility of the cables, the suspended seats vibrate during an earthquake and as a result, there is less acceleration in the structure than the foundation. A Matlab code was written to analyze and investigate the response of the system against the earthquake excitations. The findings showed that if this system is used in a building, it results in a significant reduction in the acceleration applied to the structure. A shear key system was used to control the structure for service and lateral weak loads. Moreover, the effect of vertical acceleration on the seismic behavior of the system was also investigated. Effect of the earthquake characteristic period on the system performance was studied and the optimum length of the suspension cables for a variety of the period ranges was suggested. In addition, measures have been taken for long-term functioning of the system and some practical feasibility features were also discussed. Finally, the advantages and limitations of the system were discussed and compared with the other common methods of seismic isolation.

Keywords

References

  1. Barghian, M. and Shahabi, A.B. (2007), "A new approach to pendulum base isolation", Struct. Control Hlth. Monit., 14, 177-185. https://doi.org/10.1002/stc.115.
  2. Buckle, I., Nagarajaiah, S. and Ferrell, K. (1999), "Stability of elastomeric isolation bearings", J. Struct. Eng., 125, 946-954. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:1(3).
  3. Calabrese, A., Spizzuoco, M., Strano, S. and Terzo, M. (2019), "Hysteresis models for response history analyses of recycled rubber-fiber reinforced bearings (RR-FRBs) base isolated buildings", Eng. Struct., 178, 635-644. https://doi.org/10.1016/j.engstruct.2018.10.057.
  4. Chen, P.C. and Wang, S.J. (2016), "Improved control performance of sloped rolling-type isolation devices using embedded electromagnets", Struct. Control Hlth. Monit., 24(1), 1853. https://doi.org/10.1002/stc.1853.
  5. Chu, J.Y., Ge, N., Chen, L.L. and Zhao, S.Y. (2013), "Study on characteristics of dry friction plate-reset spring seismic isolation system", Appl. Mech. Mater., 353, 1811-1814. https://doi.org/10.4028/www.scientific.net/AMM.353-356.1811.
  6. Chung, L.L., Yang, C.Y., Chen, H.M. and Lu, L.Y. (2009), "Dynamic behavior of nonlinear rolling isolation system", Struct. Control Hlth. Monit., 16(1), 32-54. https://doi.org/10.1002/stc.305.
  7. Fenz, D.M. and Constantinou, M.C. (2006), "Behaviour of the double concave Friction Pendulum bearing", Earthq. Eng. Struct. Dyn., 35, 1403-1424. https://doi.org/10.1002/eqe.589.
  8. Fenz, D.M. and Constantinou, M.C. (2008a), "Modeling triple friction pendulum bearings for response-history analysis", Earthq. Spectra, 24, 1011-1028. https://doi.org/10.1193/1.2982531.
  9. Fenz, D.M. and Constantinou, M.C. (2008b), "Spherical sliding isolation bearings with adaptive behavior: Theory", Earthq. Eng. Struct. Dyn., 37, 163-183. https://doi.org/10.1002/eqe.750.
  10. Fenz, D.M. and Constantinou, M.C. (2008c), "Spherical sliding isolation bearings with adaptive behavior: Experimental verification", Earthq. Eng. Struct. Dyn., 37, 185-205. https://doi.org/10.1002/eqe.750.
  11. Foti, D., Catalan Goni, A. and Vacca, S. (2013) "On the dynamic response of rolling base isolation systems", Struct. Control Hlth. Monit, 20, 639-648. https://doi.org/10.1002/stc.1538.
  12. Guerreiro, L., Azevedo, J. and Muhr, A.H. (2007), "Seismic tests and numerical modeling of a rolling-ball isolation system", J. Earthq. Eng., 11, 49-66. https://doi.org/10.1080/13632460601123172.
  13. Hosseini, M. and Farsangi, E.N. (2012), "Telescopic columns as a new base isolation system for vibration control of high-rise buildings", Earthq. Struct., 3(6), 853-67. https://doi.org/10.12989/eas.2012.3.6.853.
  14. Ismail, M. (2016), "Novel hexapod-based unidirectional testing and FEM analysis of the RNC isolator", Struct. Control Hlth. Monit, 23, 894-922. https://doi.org/10.1002/stc.1817.
  15. Ismail, M., Rodellar, J. and Ikhouane, F. (2012), "Seismic protection of low- to moderate-mass buildings using RNC isolator", Struct. Control Hlth. Monit., 19, 22-42. https://doi.org/10.1002/stc.421.
  16. Jangid, R.S. (2000), "Stochastic seismic response of structure isolated by rolling rods", Eng. Struct., 22, 937-946. https://doi.org/10.1016/S0141-0296(99)00041-3.
  17. Jangid, R.S. and Londhe, Y.B. (1998), "Effectiveness of elliptical rolling rods for base isolation", J. Struct. Eng., ASCE, 124, 469-472. https://doi.org/10.1061/(ASCE)0733-9445(1998)124:4(469).
  18. Japan Road Association (1980), Specification for Highway Bridges. Part V, Earthquake Resistant Design, Tokyo, Japan.
  19. Karayel, V., Yuksel, E., Gokce, T. and Sahin, F. (2017), "Spring tube braces for seismic isolation of buildings", Earthq. Eng. Eng. Vib., 16, 219-231. https://doi.org/10.1007/s11803-017-0378-9.
  20. Losanno, D., Sierra, I.E.M., Spizzuoco, M., Marulanda, J. and Thomson, P. (2019), "Experimental assessment and analytical modeling of novel fiber-reinforced isolators in unbounded configuration", Compos. Struct., 212, 66-82. https://doi.org/10.1016/j.compstruct.2019.01.026.
  21. Lu, L.Y. and Hsu, C.C. (2013a), "Experimental study of variablefrequency rocking bearings for near-fault seismic isolation", Eng. Struct., 46, 116-129. https://doi.org/10.1016/j.engstruct.2012.07.013.
  22. Lu, L.Y. and Hsu, C.C. (2013b), "Eccentric rocking bearings with a designable friction property for seismic isolation: experiment and analysis", Earthq. Spectra, 29(3), 869-895. https://doi.org/10.1193/1.4000166.
  23. Lu, L.Y. and Yang, Y.B. (1997), "Dynamic response of equipment in structures with sliding support", Earthq. Eng. Struct. Dyn., 26(1), 61-76. https://doi.org/10.1002/(SICI)1096-9845(199701)26:1.
  24. Lu, X., Lu, Q., Lu, W., Zhou, Y. and Zhao, B. (2017), "Shaking table test of a four tower high rise connected with an isolated sky corridor", Struct. Control Hlth. Monit., 25(3), 2109. https://doi.org/10.1002/stc.2109.
  25. Mokha, A., Constantinou, M. and Reinhorn, A. (1990), "Teflon bearings in base isolation I: Testing", J. Struct. Eng., 116, 438-454. https://doi.org/10.1061/(ASCE)0733-9445(1990)116:2(438).
  26. Mostaghel, N. and Khodaverdian, M. (1987), "Dynamics of resilientfriction base isolator (R-FBI)", Earthq. Eng. Struct. Dyn., 15, 379-390. https://doi.org/10.1002/eqe.4290150307.
  27. Naeim, F. and Kelly, J.M. (1999), Design Of Seismic Isolated Structures, From Theory To Practice, Wiley, New York, USA.
  28. Nakamura, Y., Saruta, M., Wada, A., Takeuchi, T., Hikone, S. and Takahashi, T. (2011), "Development of the core-suspended isolation system", Earthq. Eng. Struct. Dyn., 40, 429-447. https://doi.org/10.1002/eqe.1036.
  29. Pranesh, M. and Sinha, R. (2000), "VFPI: An isolation device for aseismic design", Earthq. Eng. Struct. Dyn., 29(5), 603-627. https://doi.org/10.1002/(SICI)1096-9845(200005)29:5.
  30. Pranesh, M. and Sinha, R. (2002), "Earthquake resistant design of structures using the variable frequency pendulum isolator", J. Struct. Eng., 128(7), 870-880. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:7(870).
  31. Quaglini, V., Gandelli, E., Dubini, P. and Limongelli, M.P. (2017), "Total displacement of curved surface sliders under nonseismic and seismic actions: A parametric study", Struct. Control Hlth. Monit., 24(12), 2031. https://doi.org/10.1002/stc.2031.
  32. Rawat, A., Ummer, N. and Matsagar, V. (2018), "Performance of bidirectional elliptical rolling rods for base isolation of buildings under near-fault earthquakes", Adv. Struct. Eng., 21(5), 675-693. https://doi.org/10.1177/1369433217726896.
  33. Robinson, W H. (1982), "Lead-rubber hysteretic bearings suitable for protecting structures during earthquakes", Earthq. Eng. Struct. Dyn., 10, 593-604. https://doi.org/10.1002/eqe.4290100408.
  34. Robinson, WH. and Tucker, A.G. (1977), "A lead-rubber shear damper", Bull. N.Z. Nat. Soc. Earthq. Eng., 3, 93-101.
  35. Ryan, K.L., Kelly, J.M. and Chopra, A.K. (2005), "Nonlinear model for lead-rubber bearings including axial-load effects", J. Eng. Mech., 131, 1270-1278. https://doi.org/10.1061/(ASCE)0733-9399(2005)131:12(1270).
  36. Skinner, R.I., Robinson, W.H. and Mcverry, G.H. (1993), An Introduction to Seismic Isolation, Wiley, New York, USA.
  37. Soni, D.P., Mistry, B.B., Jangid, R.S. and Panchal, V.R. (2011), "Seismic response of the double variable frequency pendulum isolator", Struct. Control Hlth. Monit., 18(4), 450-470. https://doi.org/10.1002/stc.384.
  38. Spizzuoco, M., Quaglini, V., Calabrese, A., Serino, G. and Zambrano, C. (2016), "Study of wire rope devices for improving the recentering capability of base isolated buildings", Struct. Control Hlth. Monit., 24(6), 1928. https://doi.org/10.1002/stc.1928.
  39. Tsai, C.S., Lin, Y.C., Chen, W.S. and Su, H.C. (2010), "Tri-directional shaking table tests of vibration sensitive equipment with static dynamics interchangeable-ball pendulum system", Earthq. Eng. Eng. Vib., 9(1), 103-112. https://doi.org/10.1007/s11803-010-9009-4.
  40. Virginio, Q., Gandelli, E. and Dubini, P. (2016), "Experimental investigation of the re-centering capability of curved surface sliders", Struct. Control Hlth. Monit., 24(2), 1870.
  41. Warn, G.P. and Whittaker, A.S. (2008), "Vertical earthquake loads on seismic isolation systems in bridges", J. Struct. Eng., 134, 1696-1704. https://doi.org/10.1061/(ASCE)0733-9445(2008)134:11(1696).
  42. Wei, B., Wang, P., He, X. and Jiang, L. (2018a), "The impact of the convex friction distribution on the seismic response of a springfriction isolation system", KSCE J. Civil Eng., 22(4), 1203-1213. https://doi.org/10.1007/s12205-017-0938-6.
  43. Wei, B., Wang, P., Yang, M. and Jiang, L. (2017), "Seismic response of rolling isolation systems with concave friction distribution", J. Earthq. Eng., 21, 325-342. https://doi.org/10.1080/13632469.2016.1157530.
  44. Wei, B., Yang, T., Jiang, L. and He, X. (2018c), "Effects of frictionbased fixed bearings on the seismic vulnerability of a high-speed railway continuous bridge", Adv. Struct. Eng., 21(5), 643-657. https://doi.org/10.1177/1369433217726894.
  45. Wei, B., Yang, T., Jiang, L. and He, X. (2018e), "Effects of uncertain characteristic periods of ground motions on seismic vulnerabilities of a continuous track-bridge system of high-speed railway", Bull. Earthq. Eng., 16(9), 3739-3769. https://doi.org/10.1007/s10518-018-0326-8
  46. Wei, B., Zuo, C., He, X. and Jiang, L. (2018a), "Numerical investigation on scaling a pure friction isolation system for civil structures in shaking table model tests", Int. J. Nonlin. Mech., 98, 1-12. https://doi.org/10.1016/j.ijnonlinmec.2017.09.005.
  47. Wei, B., Zuo, C., He, X., Jiang, L. and Wang, T. (2018d), "Effects of vertical ground motions on seismic vulnerabilities of a continuous track-bridge system of high-speed railway", Soil Dyn. Earthq. Eng., 115, 281-290. https://doi.org/10.1016/j.soildyn.2018.08.022.
  48. Xiong, W., Zhang, S.J., Jiang, L.Z. and Li, Y.Z. (2017), "Introduction of the convex friction system (CFS) for seismic isolation", Struct. Control Hlth. Monit., 24(1), 1861. https://doi.org/10.1002/stc.1861.
  49. Xiong, W., Zhang, S.J., Jiang, L.Z. and Li, Y.Z. (2018), "The multangular-pyramid concave friction system (mpcfs) for seismic isolation: a preliminary numerical study", Eng. Struct., 160, 383-394. https://doi.org/10.1016/j.engstruct.2017.12.045.
  50. Zayas, V.A., Low, S.S. and Mahin, S.A. (1990), "A simple pendulum technique for achieving seismic isolation", Earthq. Spectra, 6(2), 317-333. https://doi.org/10.1193/1.1585573.
  51. Zhou, Q., Lu, X., Wang, Q., Feng, D. and Yao, Q. (1998), "Dynamic analysis on structures base-isolated by a ball system with restoring property", Earthq. Eng. Struct. Dyn., 27, 773-791. https://doi.org/10.1002/(SICI)1096-9845(199808)27:8.