Dynamic Wheel-Rail Forces on Mismatched Joints with Ramps

The discontinuity between rail ends at a joint creates dynamic wheel-rail forces (i.e. high impact forces and wheel unloading) that can result in a range of problems including wear, deterioration, and early failure of the track structure, its components, and passing equipment. Under certain circumstances, railroads are introducing ramps (by grinding or welding) to reduce the mismatch discontinuity and produce a smoother transition in order to mitigate these dynamic wheel-rail forces. In this paper, analyses are conducted to estimate dynamic wheel-rail forces at joints having ramps and mismatches of various sizes using simplified models along with detailed NUCARS models for comparative purposes. Parametric studies are conducted to examine the effects of ramp length, direction of travel, mismatch height, and equipment speed (track class). Plots of primary shock-response-spectrum (maximum impact force on the ramp), residual shock-response-spectrum (maximum impact force after the ramp), and minimum wheel force (i.e. wheel unloading) are developed to provide guidelines on ramp length (H-rule) in order to control the maximum force by track class.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References; Tables;
  • Pagination: 7p

Subject/Index Terms

Filing Info

  • Accession Number: 01610905
  • Record Type: Publication
  • Report/Paper Numbers: JRC2016-5734
  • Files: NTL, TRIS, RITA, ATRI, USDOT
  • Created Date: Jul 8 2016 9:43AM