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Girder distribution factors for steel bridges subjected to permit truck or super load

  • Tabsh, Sami W. (Department of Civil Engineering, American University of Sharjah) ;
  • Mitchell, Muna M. (Walter P Moore)
  • Received : 2016.02.16
  • Accepted : 2016.06.18
  • Published : 2016.10.25

Abstract

There are constraints on truck weight, axle configurations and size imposed by departments of transportation around the globe due to structural capacity limitations of highway pavements and bridges. In spite of that, freight movers demand some vehicles that surpass the maximum size and legal weight limits to use the transportation network. Oversized trucks serve the purpose of spreading the load on the bridge; thus, reducing the load effect on the superstructure. For such vehicles, often a quick structural analysis of the existing bridges along the traveled route is needed to ensure that the structural capacity is not exceeded. For a wide vehicle having wheel gage larger than the standard 1830 mm, the girder distribution factors in the design specifications cannot be directly used to estimate the live load in the supporting girders. In this study, a simple approach that is based on finite element analysis is developed by modifying the AASHTO LRFD's girder distribution factors for slab-on-steel-girder bridges to overcome this problem. The proposed factors allow for determining the oversized vehicle bending moment and shear force effect in the individual girders as a function of the gage width characteristics. Findings of the study showed that the relationship between the girder distribution factor and gage width is more nonlinear in shear than in flexure. The proposed factors yield reasonable results compared with the finite element analysis with adequate level of conservatism.

Keywords

References

  1. AASHTO LRFD (2014), "LRFD bridge design specifications", 7th Edition, with 2015 and 2016 Interim Revisions, American Association of State Highway and Transportation Officials Washington, D.C.
  2. ALGOR (1998), Reference Manual, ALGOR Corporation, Pittsburgh, PA.
  3. Bae, H. and Oliva, M. (2012), "Moment and Shear load distribution factors for multigirder bridges subjected to overloads", J. Bridge Eng., ASCE, 17(3), 519-527. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000271
  4. Bishara, A.G., Liu, M.C. and El-Ali, N.D. (1993), "Wheel load distribution on simply supported skew Ibeam composite bridges", J. Struct. Eng., ASCE, 119(2), 399-419. https://doi.org/10.1061/(ASCE)0733-9445(1993)119:2(399)
  5. Committee for the Study of the Regulation of Weights, Lengths, and Widths of Commercial Motor Vehicles (2002), "Regulation of weights, lengths, and widths of commercial motor vehicles", Transportation Research Board of the National Academies, Special Report 267, Washington, D.C.
  6. Culmo, M.P., DeWolf, J.T. and DelGrego, M.R. (2004) "Behavior of steel bridges under superload permit vehicles", Transportation Research Record 1892, Transportation Research Board of the National Academies, Washington, D.C.
  7. Grimson, J.L., Commander, B.C. and Ziehl, P.H. (2008), "Superload evaluation of the Bonnet Carre spillway bridge", J. Perform. Constr. Facil., ASCE, 22(4), 253-263. https://doi.org/10.1061/(ASCE)0887-3828(2008)22:4(253)
  8. Hammada, A. (2012), "Superload crossing of Millard Avenue bridges over duck creek and CSX railroad", MS Thesis, Civil Engineering Department, University of Toledo, December.
  9. International Transport Forum (2015), "Permissible maximum dimensions of lorries in Europe", http://www.internationaltransportforum.org/IntOrg/road/pdf/dimensions.pdf, accessed February 14, 2016.
  10. Keating, P.B., Litchfield, S.C. and Zhou, M. (1995), "Overweight permit rules", Report No. 1443-1F, Texas Transportation Institute, College Station, June.
  11. Nagl, P. (2007), "Longer combination vehicles (lcv) for Asia and the Pacific region: some economic implications", UNESCAP Working Paper WP/07/02, Economic and Social Commission for Asia and The Pacific, United Nations, January.
  12. Phares, B., Wipf, T., Klaiber, F., Abu-Hawash, A. and Neubauer, S. (2005), "Implementation of physical testing for typical bridge load and superload rating", Transportation Research Record, Transportation Research Board of the National Academies, Volume 11s, Washington, D.C.
  13. Seo, J. and Hu, J.W. (2015), "influence of atypical vehicle types on girder distribution factors of secondary road steel-concrete composite bridges", J. Perform. Constr. Facil., ASCE, 29(2), 04014064. https://doi.org/10.1061/(ASCE)CF.1943-5509.0000566
  14. Seo, J., Phares, B. and Wipf, T.J. (2013), "Lateral live-load distribution characteristics of simply supported steel girder bridges loaded with implements of husbandry", J. Bridge Eng., ASCE, 19(4), 04013021. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000558
  15. Tabsh, S.W. and Tabatabai, M. (2001) "Live load distribution in girder bridges subjected to oversized trucks", J. Bridge Eng., ASCE, 5(1), 9-16.
  16. Turer, A. and Aktan, A.E. (1999), "Issues in superload crossing of three steel stringer bridges in Toledo, Ohio", Transportation Research Record 1688, Transportation Research Board of the National Academies, Washington, D.C.
  17. Woodrooffe, J., Sweatman, P., Middleton, D., James, R. and Billing, J.R. (2010) "Review of Canadian experience with the regulation of large commercial motor vehicles", NCHRP 671, Transportation Research Board of the National Academies, Washington, D.C.

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