In this study, applicability of the AASHTO LRFD girder live load distribution equations (LLDEs) for integral bridge (IB) abutments and piles is investigated. For this purpose, numerous 3-D and corresponding 2-D structural models of typical IBs are built and analyzed under AASHTO LRFD live load. In the analyses, the effect of various superstructure properties such as span length, slab thickness, girder spacing and stiffness are considered. The results from the 2-D and 3-D analyses are then used to calculate the live load distribution factors (LLDFs) for the abutments and piles of IBs as a function of the above mentioned properties. The analyses results revealed that using AASHTO LRFD LLDEs result in generally unconservative estimates of live load moment in the abutments. However, AASHTO LRFD LLDEs are found to produce exceedingly conservative estimates of live load shear in the abutments as well as live load shear and moment in the piles.
AASHTO (2007). LRFD Bridge Design Specifications, 4th Edition, Washington, D. C., USA
2.
ANSYS (2007). Structural Simulation Software, SAS IP Inc., Canonsburg, PA, USA.
3.
BarkerR.M. and PuckettJ.A. (1997). Design of Highway Bridges, John Wiley and Sons, Inc.
4.
BrenaS.F.BonczarC.CivjanS.A.DeJongJ. and CrovoD.S. (2007). “Evaluation of seasonal and yearly behavior of integral abutment bridge”, Journal of Bridge Engineering, ASCE, Vol. 12, No. 3, pp. 296–305.
5.
BurkeM.P.Jr. (1990a). “Integral bridge design is on the rise”, AISC Modern Steel Construction, Vol. 30, No. 4, pp. 9–11.
6.
BurkeM.P.Jr. (1990b). Integral Bridges, Transportation Research Record, No 1275, Transportation Research Board, National Research Council, Washington, D.C., USA.
7.
BurkeM.P.Jr. (1994). Semi-Integral Bridges: Movements and Forces, Transportation Research Record, No 1460, Transportation Research Board, National Research Council, Washington, D.C., USA, pp. 1–7.
8.
CaiC.S. (2005). “Discussion of “AASHTO LRFD load distribution factors for slab-on-girder bridges”, Practice Periodicalon Structural Design and Construction, Vol. 10, No. 3, pp. 171–176.
9.
CivjanS.A.BonczarC.BrenaS.F.DeJongJ. and CrovoD. (2007). “Integral abutment bridge behavior: Parametric analysis of a Massachusetts bridge”, Journal of Bridge Engineering, ASCE, Vol. 12, No. 1, pp. 64–71.
10.
CloughG.M. and DuncanJ.M. (1991). Foundation Engineering andbook. Second Edition, Edited by FangH. Y., Van Nostrand Reinhold, New York, USA.
11.
CookR.D. (1995). FiniteEelement Modeling for Stress Analysis, John Wiley & Sons, New York, NY.
12.
DicleliM. (2000) “A rational design approach for prestressed-concrete-girder integral bridges”, Engineering Structures, Vol. 22, No. 3, pp. 230–245.
13.
DicleliM. (2005) “Integral abutment-backfill behavior on sand soil – pushover analysis approach”, Journal of Bridge Engineering, ASCE, Vol. 10, No. 3, pp. 354–364.
14.
DicleliM. and AlbhaisiS.M. (2003) “Maximum length of integral abutment bridges supported on steel h-piles driven in sand”, Engineering Structures, Vol. 25, No. 12, pp. 1491–1504.
15.
DicleliM. and AlbhaisiS.M. (2004). “Effect of cyclic thermal loading on the performance of steel h-piles in integral bridges with stub-abutments”Journal of Constructional Steel Research, Vol. 60, No. 2, pp. 161–182.
16.
DicleliM. and ErhanS. (2008). “Effect of soil and substructure properties on live load distribution in integral abutment bridges”, Journal of Bridge Engineering, ASCE, Vol. 13, No. 5, pp. 527–539.
17.
DicleliM. and MansourM. (2003) “Seismic retrofitting of highway bridges in Illinois using friction pendulum seismic isolation bearings and modeling procedures”, Engineering Structures, Vol. 25, No. 9, pp. 1139–1156.
18.
EvansL.T. (1982). Simplified Analysis of Laterally Loaded Piles, Ph.D. Thesis. University of California, Berkeley, California, Page 211.
19.
FarajiS.TingJ.M.CrovoD.S. and ErnstH. (2001). “Nonlinear analysis of integral bridges: Finite element model”, Journal of Geotechnical and Geoinvironmental Engineering, ASCE, Vol. 127, No. 5, pp. 454–462.
20.
HusainI. and BagnariolD. (1996). Integral Abutment Bridges, Ontario Ministry of Transportation, Report SO-96-01, St. Catharines, Ontario, Canada.
21.
KhodairY.A. and HassiotisS. (2005). “Analysis of soil–pile interaction in integral abutment”, Computers and Geotechnics, Vol. 32, No. 3, pp. 201–209.
22.
LehaneB.M.KeoghD.L. and O'BrienE.J. (1999). “Simplified elastic model for restraining effects of backfill soil on integral bridges”, Computers and Structures, Vol. 73, pp. 303–313.
23.
MabsoutM.E.TarhiniK.M.FrederickG.R. and TayarC. (1997). “Finite element analysis of steel girder highway bridges”, Journal of Bridge Engineering, ASCE, Vol. 2, No. 3, pp. 83–87.
24.
MouradS., and TabshW.S. (1999). “Deck slab stresses in integral abutment bridges”, Journal of Bridge Engineering, ASCE, Vol. 4, No. 2, pp. 125–130.
25.
PatrickM.D.HuoX.S.PuckettJ.A.JablinM. and MertzD. (2006). “Sensitivity of live load distribution factors to vehicle spacing”, Journal of Bridge Engineering, ASCE, Vol. 11, No. 1, pp. 131–134.
26.
SAP2000 (2006). Integrated Finite Element Analysis and Design of Structures, Computers and Structures Inc., Berkeley, CA, USA.
27.
SoltaniA.A. and KukretiA.R. (1992). Performance Evaluation of Integral abutment Bridges, Transportation Research Record, No 1371, Transportation Research Board, National Research Council, Washington, D.C., USA, pp. 17–25.
28.
TarhiniK.M. and FrederickG.R. (1992). “Wheel load distribution in I girder highway bridges”, Journal of Structrural Engineering, ASCE, Vol. 118, No. 5, pp. 1285–1294.
29.
Wolde-TinsaeA.M.KlingerJ.E. and MullangiR. (1988a). Bridge Deck Joint Rehabilitation or Retrofitting, Final Report, Department of Civil Engineering, Maryland University, College Park, MD, USA.
30.
Wolde-TinsaeA.M.KlingerJ.E. and WhiteE.J. (1988b). “Performance of jointless bridges”, Journal of Performance of Constructed Facilities, ASCE, Vol. 2, No. 2, pp. 111–128.
31.
YousifZ. and HindiR. (2007). “AASHTO-LRFD live load distribution for beam-and-slab bridges: Limitations and applicability”, Journal of Bridge Engineering, ASCE, Vol. 12, No. 6, pp. 765–773.
32.
ZokaieT.OsterkampT.A. and ImbsenR.A. (1991). Distribution of Wheel Loads on Highway Bridges, NCHRP 12–26 Final Rep., National Cooperative Highway Research Program, Washington, D.C.
