Laboratory Investigation of Steel Tie Performance

The objectives of the proposed research is to utilize the test pit to (1) investigate into the performance of steel railway crossties in conjunction with different ballasts and (2) to explore ways to improve steel tie performance and to reduce track maintenance cost. Crossties are a very important component of conventional railway track structure. They hold rails to the correct gage (i.e., distance apart), maintain rail surface and alignment, and transfer loads from the rails into the ballast. There are three predominant crosstie material types: timber; precast, pre-stressed concrete; and steel. Steel crossties are gaining acceptance due to (1) promise of a longer service life compared with timber, (2) comparable purchase cost to timber and less than concrete, (3) ease of transport and distribution, (4) recyclability and environmental friendliness, (5) stiffness compatibility with timber; and (6) resistance to gage widening forces. However, steel crossties need special tamping to ensure good contact between tie and ballast, leading to higher installation and possibly maintenance cost than the other two ties. Steel is also susceptible to corrosion. Finally, the impact of increased tie contact pressures on ballast life is unquantified at present. In the proposed research, multiple combinations of steel ties with different ballasts will be evaluated in the laboratory test pit. The tests will simulate the traffic loading and real track environment in a realistic manner. The tests will focus on determining the optimal ballast gradation to improve contact between tie and ballast. In the meantime, numerical models utilizing discrete element method (DEM) or finite element method (FEM) will be developed to analyze the deterioration of ballast under steel crosstie loading and to verify and explain the results and findings from the laboratory tests.

    Language

    • English

    Project

    • Status: Active
    • Contract Numbers:

      NURail2013-UTK-R07

      DTRT13-G-UTC52

    • Sponsor Organizations:

      Office of the Assistant Secretary for Research and Technology

      University Transportation Centers Program
      Department of Transportation
      Washington, DC  United States  20590
    • Performing Organizations:

      University of Tennessee, Knoxville

      Center for Transportation Research
      Conference Center Building
      Knoxville, TN  United States  37996-4133
    • Principal Investigators:

      Clarke, David

    • Start Date: 20140101
    • Expected Completion Date: 20180815
    • Actual Completion Date: 0

    Subject/Index Terms

    Filing Info

    • Accession Number: 01587027
    • Record Type: Research project
    • Source Agency: National University Rail Center (NURail)
    • Contract Numbers: NURail2013-UTK-R07, DTRT13-G-UTC52
    • Files: UTC, RiP
    • Created Date: Jan 14 2016 3:45PM