Technical Reports

Characterization of Railroad Bridge Service Interruptions

  • 20
  • Feb
  • 2013
AUTHOR: Richard Joy, Mary Clara Jones, Duane Otter, and Luis Maal
SUBJECT: Bridge and Structures Safety, Track, Tracks & Structures, Track/Train Interactions
KEYWORDS: bridge problems, risk control matrix, Railroad Bridge Service Interruption Database
ABSTRACT: The Federal Railroad Administration contracted Transportation Technology Center, Inc., to study bridge problems that cause accidents or service interruptions and to use this information to evaluate the need to develop bridge monitoring systems. Existing monitoring systems and other mitigation techniques were also considered. An analysis examining frequency and severity of the events estimates that the annual risk exposure from bridge defects is about $98 million excluding costs of resulting train delays. The largest contributors are scour, hydraulic problems, and strikes from marine and highway traffic. Another major contributor is damage from derailed trains, fires, failed structural members, and moveable bridge problems. A risk control matrix was developed to match potential problems with existing control measures and identify areas in which additional controls may be warranted. Results suggest that 1) protection systems are more effective than monitoring; 2) bridge inspection is an effective control for many potential losses; and 3) significant opportunity exists for defects to be detected by others working on the railway. This may indicate that training for recognition of bridge defects may be a cost-effective way of reducing losses from accidents and service interruptions. Additionally, track displacement detectors, tilt monitors, and midspan displacement monitors should be considered for investigation.