Railroad Tie Responses to Directly Applied Rail Seat Loading in Ballasted Tracks : A Computational Study.

Details

• Creators:
  Yu, Hailing ; Jeong, David Y.
• Corporate Creators:
  John A. Volpe National Transportation Systems Center (U.S.)
• Subject/TRT Terms:
  Concrete Ties Crossties Elasticity (Mechanics) Finite Element Method Mathematical Prediction Prediction Prestressed Concrete Ties Railroad Safety Finite Element Method Railroad Ties Structural Analysis Wood Ties

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• Publication/ Report Number:
  JRC2012-74149
• Resource Type:
  Proceedings
• Corporate Publisher:
  American Society of Mechanical Engineers
• Abstract:
  This paper describes work in-progress that applies the
  
  finite element (FE) method in predicting the responses of
  
  individual railroad crossties to rail seat pressure loading in a
  
  ballasted track. Both wood and prestressed concrete crossties
  
  are examined. The concrete tie is modeled as a heterogeneous
  
  medium with prestressing wires or strands embedded in a
  
  concrete matrix. The constitutive relations employed in the
  
  models are: elasticity followed by damaged plasticity for the
  
  concrete material, linear elastic bond-slip relations with
  
  potential initiation and evolution of damage to the bond for the
  
  steel-concrete interfaces, orthotropic elasticity followed by
  
  failure dictated by orthotropic stress criteria for the wood ties,
  
  extended Drucker-Prager plasticity for the granular and
  
  frictional ballast material, and elastic half space for the
  
  subgrade. The corresponding material parameters are obtained
  
  from the open literature.
  
  Under a simplified pressure load uniformly distributed
  
  over the rail seat area, the FE method predicts tensile cracking
  
  at the tie base below the rail seats of a concrete tie and
  
  compressive failure in the rail seats of a wood tie. The rail seat
  
  force-displacement relations are obtained from the simulations.
  
  The resultant rail seat forces at which tie failures occur are
  
  compared for concrete and wood ties.
  
  The FE method appears to be a promising tool for
  
  studying the railroad tie behavior under rail seat loading
  
  conditions in a ballasted track. Experimental data will be
  
  sought to calibrate the material parameters and verify the
  
  modeling approach. Additional track components, particularly
  
  rails, rail pads and fasteners, will be incorporated in future
  
  modeling efforts. This detailed modeling approach may help to
  
  shed light on the rail seat deterioration failure mechanisms
  
  observed in some concrete ties.
  
  
• Format:
  PDF
• Collection(s):
  Volpe Center
• Main Document Checksum:
  urn:sha-512:1dcbc48b9063bacde74cb0bd50c0f8d2ab878d7c74d7741cb5614b9b66f18e769e44b9ed501a47e3e8b1182087e541546561f752ebde1425ddd4850d77f67f2e
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/9604/dot_9604_DS1.pdf
• File Type:
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