1. No category

INFORMS 2012
Shared Corridor Railway Maintenance Scheduling
Brennan M. Caughron
Graduate Research Assistant
Rail Transportation and Engineering Center (RailTEC)
University of Illinois at Urbana-Champaign
Outline
•
FRA shared corridor research needs study
•
Introduction and background
•
Maintenance planning
•
•
Strategic planning
•
Tactical scheduling
•
Integrated train and maintenance scheduling
SRC research needs
INVESTIGATING TECHNICAL CHALLENGES AND RESEARCH
NEEDS RELATED TO SHARED CORRIDORS FOR HIGH-SPEED
PASSENGER AND RAILROAD FREIGHT OPERATIONS
Project Description:
• New high speed rail (HSR) developments
in the U.S. need to address technical
challenges of shared rail corridors in the
North America rail environment
• The objectives of this project are to identify
shared rail corridor technical challenges,
existing and on-going research,
knowledge gaps and research needs
Impact on the Railroad Industry:
• Reducing the operational and program
deployment risks associated with shared
rail corridors
• Identification of critical areas to address in
planning new HSR systems
• Expediting the process of developing
efficient and safe HSR shared corridors
with better prioritization in planning
Research Sponsor:
BROAD AGENCY ANNOUNCEMENT
BAA-2010-1
Research and Demonstration Projects Supporting
the Development of High Speed and Intercity
Passenger Rail Service
Shared-Use Corridor Operating Configurations
Shared track & shared ROW
Shared track: tracks shared
between passenger and freight or
other service.
Shared right of way (ROW):
dedicated high-speed passenger
tracks separated from freight or
other service tracks up to 25’
Shared corridor: dedicated high-
Adjacent track
centers ≤ 25’
Shared corridor
High-speed rail
service
Freight or conventional
passenger rail service
speed passenger tracks separated
from freight or other service tracks
by 25-200’
Adjacent track
centers >25’ ≤ 200’
Shared Corridor Categories
•
Safety technology and operating practices
•
Rail infrastructure and equipment
•
Economic and institutional issues
•
Planning and operations
•
Infrastructure upgrade prioritization
•
Rail capacity planning
•
Train scheduling patterns
•
Passenger train schedule reliability
•
Maintenance-of-way scheduling
Railway Periodic Inspection
•
•
•
Inspection activities occur on regular
intervals depending on quality (class) of track
Inspection events
• Visual inspection monthly to 1-3 times
per week (speed, track function, traffic)
• Rail flaw detection 2 yearly or before
40MGT (with passenger traffic)
• Gauge restraint measurement system
annually for classes 8 and 9
• Automated track geometry 1-2 yearly up
to twice every 120 days
• Joint bar flaw detection
• Ground penetrating radar
• Machine vision systems
Personnel and equipment must usually
occupy track to perform inspection (some
exceptions)
Railway Periodic Maintenance
•
Track is taken out of service for
maintenance to occur
• Operation on adjacent tracks can be
impacted by maintenance activities
• Activities occur on intervals based on
cumulative traffic or time
Categories of maintenance work
• Rail relay
• Curve gauging
• Tie replacement
• Ballast cleaning
• Shoulder ballast cleaner
• Undercutting
• Surfacing
• System high-speed
• Spot surfacing
• Track renewal
• Bridge maintenance
Modeling Maintenance Scheduling
•
Numerous individuals have applied
optimization techniques to problems
related to planning and scheduling
railway maintenance
•
Model categories
•
Strategic planning
•
Tactical scheduling
• Maintenance scheduling
within existing schedule
• Integrated train and
maintenance scheduling
Strategic Maintenance Planning
•
•
•
•
•
Long term planning horizon (year)
Large time increment (week)
Schedule work crews to specific projects on the network
Generally preventative (rail, ties, ballast) vs. reactive
maintenance (fixing slow orders)
Considers various network constraints
•
•
•
Number and type of work crews
Work crew location constraints
Multiple projects on each network segment
• Benefits of maintenance blitz strategies
• Longer term disruption of rail traffic
•
•
Precedence relationship between activities
Weather or seasonal constraints
Strategic Maintenance Planning
A
Network
B
4
1
2
?
3
?
?
F
5
?
E
?
6
7
1
1
1
C
D
Strategic Planning - Previous Work
•
Grimes (1995)
•
•
•
•
Budai et al. (2006)
•
•
•
•
Genetic algorithm
Track surfacing planning
Track quality, degradation rate, various costs
Preventative maintenance scheduling problem (PMSP)
Minimize total track possession cost
Considers one network segment
Gorman et al. (2010)
•
•
•
Maintenance production gang scheduling
Minimize labor, equipment, repositioning/travel costs
Labor agreements, precedence relationships, early start/late
finish constraints
Strategic Planning - Previous Work
•
Pouryousef et al. (2010)
•
•
•
•
Refined PMSP from Budai
Simultaneous planning of several segments
Minimize track possession cost, maintenance cost, and
penalty for performing work too early
Peng et al. (2011)
•
•
•
Minimize travel costs of production gangs (travel cost more
variable than relative fixed cost of performing work)
Weather, network disruption, activity precedence constraints
included
Methodology integrated into maintenance planning process
of a class 1 railroad
Tactical Maintenance Scheduling
•
•
•
•
Short term planning horizon (weeks or days)
Small time increment (hours)
Planning for one or several lines vs. network
Scheduling maintenance activities into existing traffic
pattern
•
•
Train schedule typically adopted before maintenance
schedule
Not able to reschedule some types of rail traffic
• Passenger (+- minutes)
• Intermodal (+- hours)
• Manifest (+- hours)
•
•
•
Delay costs for different traffic types
Productivity losses for maintenance crews with interrupted
or split work windows
Limited number of crews
Tactical Maintenance Scheduling
Distance
1
2
3
Time
Shared ROW with High Speed Rail
Distance
1
2
3
Existing RR
New HSR
Time
High speed trains
Previous Work
Higgins (1998)
• Schedule maintenance activities and crews in an existing
rail traffic pattern
• Decision support tool for operation and maintenance
managers
• Activities considered
•
•
•
•
•
•
Inspection
Cross ties
Rail (replacement and grinding)
Ballast cleaning
Track surfacing
Case study line (302 km, 45 sidings)
•
Manually constructed maintenance schedule
• 7.4% increase in activity finishing time
• 18% increase in train and maintenance delay
Integrated Train and Maintenance Scheduling
•
•
•
Maintenance activities and train schedules planned
simultaneously
Objective function: minimize total cost of train delay and
maintenance activities
North American operating environment
•
•
•
•
•
European operating environment
•
•
•
•
Unscheduled trains (bulk commodities)
Scheduled trains (passenger, intermodal, manifest)
Long trains
Long shipment distances (2,000+ miles)
Scheduled trains (freight and passenger)
Meet and pass planning
Temporal separation of traffic types
Integrated train and maintenance scheduling may have
limited application in the N. American operating
environment
Previous Work
Albrecht et al. (2010)
•
•
•
•
•
Problem space search (PSS) meta-heuristic
Simultaneous scheduling of maintenance activities and rail
traffic
Minimize total delay to rail traffic and maintenance crews
Considered additional metric – delay experienced by worst
performing train (better consideration of distribution of
delays)
Applied to case study line
• Total delay reduced 17% vs. manual schedule
• Maximum delay reduced 34%
Shared Corridor Research Needs
•
Strategic planning
•
•
Passenger traffic delay constraints related to network and
seasonal conditions
Tactical scheduling
•
•
•
•
•
Delay cost for different train types
Cost of lost maintenance productivity in interrupted or split
windows
Threshold for integrated rail traffic and maintenance
planning
Threshold for temporal separation (maintenance at night,
rail traffic during the day)
Tactical scheduling with stochastic train and maintenance
events (longer planning horizon, more uncertainty)
Questions?
Brennan M. Caughron
bcaughr2@illinois.edu