Earthquakes and Structures

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Response of Skew Bridges with permutations of geometric parameters and bearings articulation

  • Fakhry, Mina F. (Structural Engineering Department, Cairo University) ;
  • ElSayed, Mostafa M. (Structural Engineering Department, Cairo University) ;
  • Mehanny, Sameh S.F. (Structural Engineering Department, Cairo University)
  • Received : 2019.06.19
  • Accepted : 2019.09.23
  • Published : 2019.11.25
⟨ Previous Next ⟩

Abstract

Understanding the behavior of skew bridges under the action of earthquakes is quite challenging due to the combined transverse and longitudinal responses even under unidirectional hit. The main goal of this research is to assess the response of skew bridges when subjected to longitudinal and transversal earthquake loading. The effect of skew on the response considering two- and three- span bridges with skew angles varying from 0 to 60 degrees is illustrated. Various pier fixities (and hence stiffness) and cross-section shapes, as well as different abutment's bearing articulations, are also studied. Finite-element models are established for modal and seismic analyses. Around 900 models are analyzed under the action of the code design response spectrum. $Vis-{\grave{a}}-vis$ modal properties, the higher the skew angle, the less the fundamental period. In addition, it is found that bridges with skew angles less than 30 degrees can be treated as straight bridges for the purpose of calculating modal mass participation factors. Other monitored results are bearings' reactions at abutments, shear and torsion demand in piers, as well as deck longitudinal displacement. Unlike straight bridges, it has been typically noted that skew bridges experience non-negligible torsion and bi-directional pier base shears. In a complementary effort to assess the accuracy of the conducted response spectrum analysis, a series of time-history analyses are applied under seven actual earthquake records scaled to match the code design response spectrum and critical comparisons are performed.

Keywords

References

  1. AASHTO LRFD (2008), American Association of State Highway and Transportation Officials, Washington, D.C., USA.
  2. Apirakvorapinit, P. (2005), "Analytical investigation of seismic damage to skewed bridges in california", Ph.D. Dissertation, Illinois Institute of Technology, Chicago, USA.
  3. Apirakvorapinit, P., Mohammadi, J. and Shen, J. (2012), "Analytical investigation of potential seismic damage to a Skewed Bridge", Prac. Period. Struct. Des. Constr., ASCE, 16(1), 5-12. https://doi.org/10.1061/(ASCE)SC.1943-5576.0000094.
  4. Ayoub, E., Malek, C. and Helmy, G. (2013), "Effect of skewness on bridges subjected to seismic loading", IABSE Conference Rotterdam, Netherlands, May.
  5. Ayoub, E., Malek, C. and Helmy, G. (2014), "Response of three span skew bridges subjected to longitudinal and transversal earthquake loading", 37th IABSE Symposium, Madrid, Spain, September.
  6. Behnamfar, F. and Velni M.T. (2019), "A rapid screening method for selection and modification of ground motions for time history analysis", Earthq. Struct., 16(1), 29-39. https://doi.org/10.12989/eas.2019.16.1.029.
  7. Chen, L. and Chen, S. (2016), "Seismic fragility performance of skewed and curved bridges in low-to-moderate seismic region", Earthq. Struct., 10(4), 789-810. https://doi.org/10.12989/eas.2016.10.4.789.
  8. CSI, SAP2000 Integrated Software for Structural Analysis and Design, Computers and Structures Inc., Berkeley, California.
  9. ECP 201 (2008) Egyptian Code of Practice no. 201 for Determination of Loads and Forces for the Structural and Civil Works, Research Centre for Housing and Construction, Ministry of Housing, Utilities and Urban Planning, Cairo, Egypt.
  10. EN 1998-2 Eurocode 8 (2005) Design of Structures for Earthquake Resistance, Part 2: Bridges, Comite Europeen de Normalisation, Brussels, Belgium.
  11. Fakhry, M.F. (2019), "Investigating seismic response of skew bridges for various permutations of geometric design parameters and abutment bearings articulations", M.Sc. Thesis, Faculty of Engineering, Cairo University
  12. Farag, M.M.N, Mehanny, S.S.F. and Bakhoum, M.M. (2015), "Establishing optimal gap size for precast beam bridges with a buffer-gap-elastomeric bearings system", Earthq. Struct., 9(1), 195-219. https://doi.org/10.12989/eas.2015.9.1.195.
  13. Ghosh, J. and Padgett, J. E. (2012), "Impact of multiple component deterioration and exposure conditions on seismic vulnerability of concrete bridges", Earthq. Struct., 3(5), 649-673. https://doi.org/10.12989/eas.2012.3.5.649.
  14. Kun, C., Yang, Z. and Chouw, N. (2018), "Seismic response of skewed bridges including pounding effects", Earthq. Struct., 14(5), 467-476. https://doi.org/10.12989/eas.2018.14.5.467.
  15. Liu, Y., Paolacci, F. and Lu, D.G. (2017), "Seismic fragility of a typical bridge using extrapolated experimental damage limit states", Earthq. Struct., 13(6), 599-611. https://doi.org/10.12989/eas.2017.13.6.599.
  16. Maleki, S. (2001), "Free vibration of skewed bridges", J. Vib. Control, 7(7), 935-952. https://doi.org/10.1177/107754630100700701.
  17. Maleki, S. (2002), "Deck modeling for seismic analysis of skewed slab- girder bridges", Eng. Struct., 24(10), 1315-1326. https://doi.org/10.1016/S0141-0296(02)00066-4.
  18. Maleki, S. (2005), "Seismic modeling of skewed bridges with elastomeric bearings and side retainers", J. Bridge Eng., ASCE, 10(4), 442-449. https://doi.org/10.1061/(ASCE)1084-0702(2005)10:4(442).
  19. Markous, N.A., Mehanny, S.S.F. and Bakhoum, M.M. (2014), "Scaling of earthquake ground motion records for seismic analysis and design of bridges", J. Egypt. Soc. Eng., 53(2).
  20. Mehanny, S.S.F. (2009), "A broad-range power-law form scalar-based seismic intensity measure", Eng. Struct., 31(7), 1354-1368. https://doi.org/10.1016/j.engstruct.2009.02.003.
  21. Meng, J.., and Lui, E. (2000), "Seismic analysis and assessment of a skew highway bridge", Eng. Struct., 22(11), 1433-1452. https://doi.org/10.1016/S0141-0296(99)00097-8.
  22. Ramanathan, K., Jeon, J.S., Zakeri, B., DesRoches, R. and Padgett, J.E. (2015), "Seismic response prediction and modeling considerations for curved and skewed concrete box-girder bridges", Earthq. Struct., 9(6), 1153-1179. https://doi.org/10.12989/eas.2015.9.6.1153.
  23. Shome, N. and Cornell, C.A. (1999), "Probabilistic seismic demand analysis of nonlinear structures", Rep. No. RMS-35, Reliability of Marine Structures, Dept. of Civil and Eng., Stanford University, March.
  24. Wakefield, R., Nazmy, A. and Billington, D. (1991), "Analysis of seismic failure in skew RC bridge", J. Struct. Eng., ASCE, 117(3), 972-986. https://doi.org/10.1061/(ASCE)0733-9445(1991)117:3(972).
  25. Whelan, M. and Janoyan, K. (2012), "Assessment of simplified linear dynamic analysis of a multispan Skew Bridge on steelreinforced elastomeric bearings", J. Bridge Eng., ASCE, 16(1), 151-160. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000218.

Cited by

  1. Response modification factor and seismic fragility assessment of skewed multi-span continuous concrete girder bridges vol.20, pp.4, 2021, https://doi.org/10.12989/eas.2021.20.4.389