Optimizing Performance of Railroad Rail through Artificial Wear

Localized plastic deformation from rolling contact and friction at the wheel-rail interface induces a severe multi-axial internal stress state in the rail head, resulting in both surface and subsurface nucleation of cracks. Catastrophic failure of railroad rail is often caused by such railhead fatigue defects. Fatigue-induced broken-rail derailments of trains can result in significant financial loss to stakeholders as well as human casualties. The objectives of the proposed project are to reduce the occurrence of fatigue-induced derailments of trains while simultaneously extending the service life of rail. There is worldwide field evidence that rail-head grinding, a form of applying artificial wear to a railhead, is a cost-effective method to increase the useful life of rails. The current use of rail grinding in the rail industry is to maintain a smooth running surface upon which the wheels of trains roll. Other mechanical effects of rail-head grinding are not fully understood, and thus the design of grinding schedules currently depends upon intuition, prior experience, and historical application. To achieve the goals of this project, wear and fatigue models will be developed to simultaneously assess three volumetric regions of the rail head: surface, near-surface, and subsurface. The proposed wear and fatigue models of this project will be integrated into a generalized multi-axial analysis accounting for both natural and artificial wear at the running surface and fatigue crack nucleation within near-surface and subsurface volumetric regions. The proposed multi-axial framework will be validated against field measurements and observations and incorporated into a genetic algorithm (GA) optimization module to help identify meaningful pareto frontiers associated with alternative scenarios of applying artificial wear through railhead grinding. To meet these objectives, the proposed research project will present (1) finite element analyses of wheel-rail contact with nonlinear multiaxial material hardening, (2) analytical studies of at-surface, nearsurface and subsurface wear (natural and artificial) and fatigue, (3) a survey and data collection program that includes assessments of wear, fatigue and rail head grinding costs from US railroad companies, (4) the validation and correlation of the results from wear and fatigue mechanistic models against experiments and field results, and (5) the development of a GA-based framework that will provide a set of optimal rail head grinding schedules and geometric profiles of the railhead for given loading conditions.

• Record URL:
  http://www.utrgv.edu/railwaysafety/research/infrastructure/railroad-rail-performance/index.htm

Language

• English

Project

• Status: Completed
• Funding: $131,720
• Contract Numbers:

  DTRT13-G-UTC59

• Sponsor Organizations:

  Research and Innovative Technology Administration

  University Transportation Centers Program
  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  Texas A&M University, College Station

  Zachry Department of Civil Engineering
  3136 TAMU
  College Station, TX  United States  77843-3136
• Principal Investigators:

  Fry, Gary

• Start Date: 20140101
• Expected Completion Date: 20161231
• Actual Completion Date: 20161231
• Source Data: RiP Project 36696

Subject/Index Terms

• TRT Terms: Derailments; Fatigue (Mechanics); Finite element method; Genetic algorithms; Grinding; Optimization; Railhead; Rolling contact; Service life; Wear
• Subject Areas: Maintenance and Preservation; Railroads;

Filing Info

• Accession Number: 01528387
• Record Type: Research project
• Source Agency: University Transportation Center for Railway Safety
• Contract Numbers: DTRT13-G-UTC59
• Files: UTC, RIP
• Created Date: Jun 19 2014 1:00AM