Creep Behavior of High-Speed Railway Prestressed Concrete Girders for 500 Days

Most high-speed railways in operation today use ballastless railroad track girders made of prestressed concrete. Long-term deflections due to creep and shrinkage can have significant effects on the safety and serviceability of these girders. This study reports on an experimental study that was conducted regarding the creep behavior of high-speed railway prestressed concrete girders. The study tested six concrete beams with I cross sections with a scale of 1:5 for approximately 500 days. The effects of the types of concrete, methods of tensioning, and stress differences between the upper and lower fibers of the midspan sections on creep cambers were investigated. The findings showed that midspan creep cambers, creep strains, steel reinforcement strains and prestressing reinforcement strains of the prestressed concrete beams all exhibit a high rate of increase for the early period after prestress tensioning, followed by a more gradual rate of increase. Prestressed high performance concrete girders showed a better creep behavior compared to prestressed concrete girders. Using a two-step tensioning method also showed better creep behavior compared to using one-step tensioning methods. Better creep behavior is found with a lower stress difference between the upper and lower fibers of the section at midspan. A design proposal for predicting the creep cambers at the midspan of high-speed railway prestressed concrete girders is suggested based on the findings. The calculated values using the suggested design proposal appear to correspond well with available test results, although more research is needed to accurately define the modifiers in the proposed formula.

  • Availability:
  • Authors:
    • Xue, Weichen
    • Liu, Ting
    • Wang, Wei
    • Hu, Yuming
  • Publication Date: 2011-7

Language

  • English

Media Info

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Filing Info

  • Accession Number: 01355996
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Sep 16 2011 1:10AM