Structural Engineering and Mechanics

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Experimental analysis of an asymmetric reinforced concrete bridge under vehicular loads

  • Thambiratnam, D.P. (Physical Infrastructure Centre, School of Civil Engineering, Queensland University of Technology) ;
  • Brameld, G.H. (Physical Infrastructure Centre, School of Civil Engineering, Queensland University of Technology) ;
  • Memory, T.J. (Madsen & Giersing, Consulting Engineers)
  • Published : 2000.01.25
⟨ Previous Next ⟩

Abstract

Dynamic response of a three span continuous bridge has been determined by full scale experiments on the bridge. In the experiments, a heavy vehicle was driven across the bridge at different speeds and along different lanes of travel and the strains were recorded at different locations. The bridge was made of reinforced concrete and was asymmetric in plan and in elevation. Frequencies and modes of vibration excited by the vehicle were determined. The dependence of the dynamic amplification on bridge location and vehicle speed was investigated and dynamic amplifications up to 1.5 were recorded, which was higher than values predicted by bridge design codes. It was evident that when this asymmetric bridge was loaded by an asymmetric forcing function, higher modes, which are lateral and/or torsional in nature, were excited. Dynamic modulus of elasticity and the support stiffness influenced the natural frequencies of the bridge, which in turn influenced the dynamic amplifications. Larger than anticipated dynamic amplification factors and the excitation of lateral and/or torsional modes should be of interest and concern to bridge engineers.

Keywords

References

  1. AUSTROADS Bridge Design Code (1992), National Association of Australian State Road Authorities, Sydney, NSW, Australia.
  2. Bahkt, B. and Pinjarkar, S.G. (1989), "Review of dynamic testing of highway bridges", TRB 880532, Research and Development Branch, Ontario Ministry of Transportation, Ontario, Canada.
  3. Billing, J.R. (1982), "Dynamic loading and testing of bridges in Ontario, 1980", Proceedings of the International Conference on Short and Medium Span Bridges, Toronto, Ontario, Canada.
  4. Billing, J.R. and Green, R. (1984) "Design provisions for dynamic loading of highway bridges", Transportation Research Report 950, Ontario Ministry of Transportation and Communications, Downsview, Ontario, Canada, 94-103.
  5. Cantieni, R. (1983), "Dynamic load tests on highway bridges in Switzerland, 60 years experience of EMPA", Report No 271, EMPA, Swiss Federal Laboratories for Materials Testing and Research, Dubendorf, Switzerland.
  6. Cantieni, R. (1992), "Dynamic behaviour of highway bridges under the passage of heavy vehicles", EMPA Report No. 220, Swiss Federal Laboratories for Materials Testing and Research, Dubendorf, SWItzerland.
  7. Huang, D., Wang, T. and Shahawy, M. (1995), "Vibration of thin walled box girder bridges excited by vehicles", Journal of Structural Division, ASCE, 121(9), 1330-1337, September. https://doi.org/10.1061/(ASCE)0733-9445(1995)121:9(1330)
  8. Hwang, E. and Nowak A.S. (1991), "Simulation of dynamic load for bridges", ASCE, Journal of Structural Engineering, May, 1413-1434.
  9. Memory, T.J. Brameld, G.H. and Thambiratnam, D.P. (1991), "A simplified method for estimating the natural frequency of bridge superstructures", Proceedings of AUSTROADS Bridges Conference, Bridges-Part of the Transport System, Brisbane, Australia.
  10. Memory, T.J. (1992), "On the dynamic behaviour of highway bridges" , Master of Engineering Sciences Thesis, Queensland University of Technology, Australia.
  11. Memory, T.J., Thambiratnam; D.P. and Brameld, G.H. (1995), "Free vibration analysis of bridges", Journal of Engineering Structures, 17(10),705-713. https://doi.org/10.1016/0141-0296(95)00037-8
  12. Ontario Highway Bridge Design Code (1993), Ministry of TranspOItation and Communications, Ontario, Canada.
  13. Ranchigoda, S. (1992), "The dynamic amplification of continuous span bridges" , Bachelor of Engineering Sciences Thesis, Queensland University of Technology, Australia.
  14. Tan, G, Brameld, G.H and Thambiratnam, D.P. (1998), "Dynamic amplifications in concrete bridges due to moving loads", Journal of Engineering Structures, 20(1-2), 54-61. https://doi.org/10.1016/S0141-0296(97)00051-5

Cited by

  1. Dynamic behavior of long-span box girder bridges subjected to moving loads: Numerical analysis and experimental verification vol.42, pp.18-19, 2005, https://doi.org/10.1016/j.ijsolstr.2005.02.020
  2. Dynamic response of a curved bridge under moving truck load vol.24, pp.10, 2002, https://doi.org/10.1016/S0141-0296(02)00059-7