DOI QR코드

DOI QR Code

Rocking behavior of bridge piers with spread footings under cyclic loading and earthquake excitation

  • Hung, Hsiao-Hui (National Center for Research on Earthquake Engineering) ;
  • Liu, Kuang-Yen (National Center for Research on Earthquake Engineering) ;
  • Chang, Kuo-Chun (National Center for Research on Earthquake Engineering)
  • Received : 2014.02.19
  • Accepted : 2014.08.22
  • Published : 2014.12.25

Abstract

The size of spread footings was found to be unnecessarily large from some actual engineering practices constructed in Taiwan, due to the strict design provisions related to footing uplift. According to the earlier design code in Taiwan, the footing uplift involving separation of footing from subsoil was permitted to be only up to one-half of the foundation base area, as the applied moment reaches the value of plastic moment capacity of the column. The reason for this provision was that rocking of spread footings was not a favorable mechanism. However, recent research has indicated that rocking itself may not be detrimental to seismic performance and, in fact, may act as a form of seismic isolation mechanism. In order to clarify the effects of the relative strength between column and foundation on the rocking behavior of a column, six circular reinforced concrete (RC) columns were designed and constructed and a series of rocking experiments were performed. During the tests, columns rested on a rubber pad to allow rocking to take place. Experimental variables included the dimensions of the footings, the strength and ductility capacity of the columns and the intensity of the applied earthquake. Experimental data for the six circular RC columns subjected to quasi-static and pseudo-dynamic loading are presented. Results of each cyclic loading test are compared against the benchmark test with fixed-base conditions. By comparing the experimental responses of the specimens with different design details, a key parameter of rocking behavior related to footing size and column strength is identified. For a properly designed column with the parameter higher than 1, the beneficial effects of rocking in reducing ductility and the strength demand of columns is verified.

Acknowledgement

Supported by : National Science Council of Taiwan

References

  1. AASHTO (2009), Guide Specifications for LRFD Seismic Bridge Design, (1st Edition), Washington, DC
  2. Apostolou, M., Gazetas, G. and Garini, E. (2007), "Seismic response of slender rigid structures with foundation uplifting", Soil. Dyn. Earthq. Eng., 27, 642-654. https://doi.org/10.1016/j.soildyn.2006.12.002
  3. Aslam, M., Goggen, W.G. and Scalise, D.T. (1980), "Earthquake rocking response of rigid bodies", J Struct . Div. (ASCE), 106(2), 377-392.
  4. Chopra, A.K. and Yim, C.S. (1985), "Simplified earthquake analysis of structures with foundation uplift", J Struct. Eng. (ASCE), 111(4), 906-930. https://doi.org/10.1061/(ASCE)0733-9445(1985)111:4(906)
  5. Cremer, C., Pecker, A. and Davenne, L. (2001), "Cyclic macro-element for soil-structure interaction:material and geometrical non-linearities", Int. J. Numer. Anal. Met., 25 (13), 1257-1284. https://doi.org/10.1002/nag.175
  6. Deng, L., Kutter, B.L. and Kunnath, S. (2012), "Centrifuge modeling of bridge systems designed for rocking foundations", J. Geotech. Geoenviron. Eng. (ASCE). 138(3), 225-344.
  7. Deng, L. and Kutter, B.L. (2012), "Characterization of rocking shallow foundations using centrifuge model tests", Earthq. Eng. Struct. Dyn., 41, 1043-1060. https://doi.org/10.1002/eqe.1181
  8. Espinoza A, Mahin S (2006) Rocking of bridge piers subjected to multi-directional earthquake excitation. Fifth National Seismic Conference on Bridge & Highways, San Francisco, CA, September 18-20
  9. FEMA (1997), NEHRP Guidelines and Commentary for the Seismic Rehabilitation of Buildings, Reports No. 273, Washington, D.C.
  10. FHWA (2006), Seismic Retrofitting Manual for Highway Structures: Part 1- Bridges, Reports No. FHWAHRT-05-032.
  11. Gajan, S., Kutter, B.L., Phalen, J.D., Hutchinson, T.C. and Martin, G.R. (2005), "Centrifuge modeling of load-deformation behavior of rocking shallow foundation", Soil Dyn. Earthq. Eng., 25, 773-783. https://doi.org/10.1016/j.soildyn.2004.11.019
  12. Gajan, S. and Kutter, B.L. (2008), "Capacity, settlement, and energy dissipation of shallow footings subjected to rocking", J. Geotech. and Geoenviron. Eng. (ASCE) ,134(8), 1129-1141. https://doi.org/10.1061/(ASCE)1090-0241(2008)134:8(1129)
  13. Gajan, S., Hutchinson, T.C., Kutter, B.L., Raychowdhury, P., Ugalde, J.A. and Stewart, J.P. (2007), Numerical Models for Analysis and Performance-based Design of Shallow Foundations Subjected to Seismic Loading. PEER 2007/4, Pacific Earthquake Engineering Research Center, University of California, Berkeley
  14. Grange, S., Kotronis, P. and Mazars, J. (2009), "A macro-element to simulate 3D soil-structure interaction considering plasticity and uplift", Int. J. Solids Struct., 46, 3651-3663. https://doi.org/10.1016/j.ijsolstr.2009.06.015
  15. Grange, S., Kotronis, P. and Mazars, J. (2009), "A macro-element to simulate dynamic soil-structure interaction", Eng. Struct., 31, 3034-3046. https://doi.org/10.1016/j.engstruct.2009.08.007
  16. Grange, S., Botrugno, L., Kotronis, P. and Tamagnini, C. (2011), "The effects of soil-structure interaction on a reinforced concrete viaduct", Earthq. Eng. Struct. Dyn., 40, 93-105. https://doi.org/10.1002/eqe.1034
  17. Harden, C., Hutchinson, T.C., Kutter, B.L. and Martin, G. (2005), Numerical Modeling of the Nonlinear Cyclic Response of Shallow Foundations, PEER 2005/04, Pacific Earthquake Engineering Research Center, University of California, Berkeley
  18. Housner, G.W. (1963), "The behavior of inverted pendulum structures during earthquakes", Bull. Seismol .Soc. Am., 53(2), 403-417.
  19. Hung, H.H., Liu, K.Y., Ho, T.H. and Chang, K.C. (2011), "An experimental study on the rocking response of bridge piers with spread footing foundations", Earthq. Eng. Struct. Dyn., 40, 749-769. https://doi.org/10.1002/eqe.1057
  20. Kawashima, K. and Nagai, T. (2006), "Effectiveness of rocking seismic isolation on bridges", 4th International Conference on Earthquake Engineering, Taipei, Taiwan, October 12-13.
  21. Kelly, T.E. (2009), "Tentative seismic design guidelines for rocking structure", Bull. NZ Soc. Earthq. Eng., 42(4), 239-274.
  22. Kutter, B.L., Martin, G., Hutchinson, T.C., Harden, C., Gajan, S. and Phalen, J. (2005), Workshop on Modeling of Nonlinear Cyclic Load-deformation Behavior of Shallow Foundations, PEER 2005/14, Pacific Earthquake Engineering Research Center, University of California, Berkeley.
  23. MOTC (2008), Seismic Design Code for Highway Bridges, Taiwan (in Chinese).
  24. Palmeri, A,, Makris, N, (2008), "Response analysis of rigid structures rocking on viscoelastic foundation", Earthq. Eng. Struct. Dyn., 37, 1039-1063. https://doi.org/10.1002/eqe.800
  25. Paolucci, R., Shirato, M. and Yilmaz, M.T. (2008), "Seismic behaviour of shallow foundations: shaking table experiments vs numerical modeling", Earthq. Eng. Struct. Dyn., 37, 577-595. https://doi.org/10.1002/eqe.773
  26. Psycharis, I. (1982), Dynamic Behavior of Rocking Structures Allowed to Uplift, EERL Report 81-02, California Institute of Technology.
  27. Sakellaraki D, Watanabe G, Kawashima K (2005) Experimental rocking response of direct foundations of bridges. Second International Conference on Urban Earthquake Engineering, Tokyo Institute of Technology, Tokyo, Japan, March 7-8, 497-504
  28. Shirato, M., kouno, T., Asai, R., Nakani, S., Fukui, J. and Paolucci, R. (2008), "Large-scale experiments on nonlinear behavior of shallow foundations subjected to strong earthquakes", Soil Found., 48(5), 673-692. https://doi.org/10.3208/sandf.48.673
  29. Taylor, P.W., Bartlett, P.E. and Wiessing, P.R. (1981), "Foundation rocking under earthquake loading", Proceedings of the 10th International Conference on Soil Mechanics and Foundation Engineering, 3, 313-322.
  30. Tso, W.K. and Wong, C.M. (1989), "Steady state rocking response of rigid blocks, Part I: analysis", Earthq. Eng. Struct. Dyn., 18, 89-106. https://doi.org/10.1002/eqe.4290180109
  31. Ugalde, J.A., Kutter, B.L., Jeremic, B. and Gajan, S. (2007), "Centrifuge modeling of rocking behavior of bridges on shallow foundations", 4th International Conference on Earthquake Geotechnical Engineering, Thessaloniki, Greece, June 25-28.
  32. Ugalde, J.A., Kutter, B.L. and Jeremic, B. (2010), Rocking Response of Bridges on Shallow Foundations, EER-2010/101, Pacific Earthquake Engineering Research Center, University of California, Berkeley
  33. Wiessing, P.R. (1979), Foundation Rocking on Sand. School of Engineering Report No. 203, University of Auckland, New Zealand.
  34. Yang, Y.B., Hung, H.H. and He, M.J. (2000), "Sliding and rocking response of rigid blocks due to horizontal excitations", Struct. Eng. Mech., Int. J., 9(1), 1-16. https://doi.org/10.12989/sem.2000.9.1.001
  35. Yim, C.S., Chopra, A.K. and Panzien, J. (1980), "Rocking response of rigid blocks to earthquakes", Earthq. Eng. Struct. Dyn., 8, 565-587. https://doi.org/10.1002/eqe.4290080606
  36. Yim, C.S. and Chopra, A.K. (1984), "Earthquake response of structures with partial uplift on winkler foundation", Earthq. Eng. Struct. Dyn., 12, 263-281. https://doi.org/10.1002/eqe.4290120209
  37. Zhang, J. and Makris, N. (2001), "Rocking response of free-standing blocks under cycloidal pulses", J. Eng. Mech. (ASCE), 127(5), 473-483.

Cited by

  1. Pushover and shaking table tests on a rocking-governed column-footing model on dry dense sand vol.41, pp.3, 2018, https://doi.org/10.1080/02533839.2018.1454858