Massachusetts Bay Transportation Authority (MBTA)

Blue Line Traction Power Simulation

Boston, Massachusetts

As part of the Blue Line No.5 car procurement, a traction power study was performed to determine the impacts the new car would have on the existing traction power system.  The power study modeled the new No. 5 car in a 6-car consist operating under peak (rush-hour) conditions.  The Blue Line traction power system was modeled with composite 3rd rail in the tunnel from Bowdoin to Airport station.  At Airport station the traction power supply transitions to an overhead contact system (OCS) for the remainder of the line to Wonderland station. 

The main concern addressed by the study was to resolve whether the new car operating under maximum train length and peak period headways would cause any rail voltage degradation that would negatively affect trip times.  At the same time, the loadings of the Blue Line traction power substations were evaluated versus the nameplate ratings of each unit to confirm that no overloading was occurring in the simulation.

The No. 5 car is a modern electronically-controlled vehicle equipped with AC inverter drive propulsion system.  The No. 5 cars are operating in the interim “phase in” period with the existing, cam-controlled, No. 4 cars until the complete Blue Line fleet is replaced.

The MBTA has ordered 94 new No. 5 cars (47 pairs) with stainless steel bodies from Siemens Transportation Systems. The first of the new cars began service on February 20, 2008. The entire No. 5 fleet is expected to be in service by the end of 2009.

The scenarios used to perform the study included assessment of the traction power system with various vehicle configurations, including the propulsion system with current limiting and/or reduced acceleration.  The study also considered the impact of new substations, increased nominal voltage at the existing substations and the installation of additional conductors to the distribution system and substation feeders.

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Florida Department of Transportation (FDOT)

SunRail Commuter Rail Project

Orlando and Central Florida Area

The Central Florida Commuter Rail Transportation (“CFCRT”) project, also known as “SunRail” was sponsored by the Florida Department of Transportation (“FDOT”) and involves the purchase by FDOT of 61.5 miles of the “A” Line of CSX Transportation, Inc. between DeLand and Poinciana, Florida.  With the acquisition, FDOT plans to upgrade the rail facilities in the Corridor, including double-tracking, crossovers and a new signaling/dispatching system, in order to support high frequency commuter rail service on the line.  In addition, the “A” Line will continue to support CSXT freight and Amtrak intercity passenger service.  LTK was called upon to provide a Verified Statement to the Surface Transportation Board in support of FDOT’s application to take title to the “A” Line.

OS2-FDOTThe Verified Statement was based on operations planning/line capacity analyses, performed by another firm, for commuter rail operations where commuter traffic shares track with freight traffic.  The analyses are based on the use of simulation models to identify the infrastructure that would be required on the Corridor to reliably support commuter, intercity passenger and freight service, both now and in the future. 

FDOT plans to improve the line following purchase from CSXT from a generally single track railroad with passing sidings to a generally double-track railroad with universal 45 mph crossovers approximately every five miles and a new high-capacity, four-aspect bi-directional signal system on both tracks.  Because of structural, environmental and community considerations, some short sections of single track will remain in the proposed Corridor track configuration.

CSXT plans to divert or reroute some existing road freight trains from the Corridor to CSXT’s parallel, freight-only “S” Line, including intermodal and automotive trains that will operate to a new terminal facility being developed off of the Corridor. 

The Verified Statement is also based on the CFCRT Freight Service Plan for the Corridor, developed in cooperation with CSXT.  The Freight Service Plan utilized actual data from CSXT to identify local set-off, pick-up and switching requirements and road freight service using current “A” line operations through the Corridor as a starting point and then accounting for the train diversions to the “S” line and the relocation of Taft Yard terminal functions. 

Simulation software was used to model over-the-road travel times of CSXT trains using 90th percentile (longest) train lengths and 10th percentile (lowest) horsepower-to-ton ratios to ensure conservatism in the results.  These simulated occupancies, coupled with similar simulation output for the four daily (two each way) Amtrak trains operating over the entire Corridor and the two daily (one each way) Amtrak Auto Trains operating on the Corridor north of Sanford, Florida, along with the proposed commuter rail service, were used to evaluate the feasibility of such operations over a 24-hour weekday period.  In general, the plan called for a level of activity more intense than the projections for a typical day in order to ensure operational flexibility, room for growth and CSXT’s ability to serve its freight customers should a very large percentage require switching on the same day.  For the analysis, Amtrak trains were assumed to have a high degree of schedule variability, both in terms of potential enroute delays and long-term operational constraints that might result in significant schedule shifts over time. 

The service plan was then reviewed by CSXT and adjustments were made to optimize the plan.  The CFCRT Freight Service Plan – Revision 5 that resulted was adopted by CSXT and FDOT in October, 2006.  It formed the basis for the Central Florida Operating & Maintenance Agreement between CSXT and FDOT.

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National Railroad Passenger Corp. (Amtrak)

Train Performance Simulation of High-Speed Trainsets

Northeast Corridor

LTK supported Amtrak in the conceptual design, proposal review and procurement of Acela high-speed trainsets for Northeast Corridor service.  The Acela fleet consists of 20 trainsets, comprising 40 power cars, 120 passenger cars, and one high-speed track geometry car.  LTK also assisted in the procurement of three dedicated maintenance facilities and carbuilder-supplied management services to maintain the fleet.

OS3-AmtrakAcelaAs part of proposal review activities, LTK performed Train Performance Calculations (TPC) to assess the estimated trip times associated with trainset designs proposed by six prospective carbuilders.  Trip times for the New York - Boston and New York - Washington route segments were separately calculated. The goal of this effort was to determine the ability of each design to meet Amtrak’s trip time requirements under Northeast Corridor operating conditions.

TPC simulations utilized proposer-supplied propulsion, braking, weight, dimensional and carbody tilting data in combination with Amtrak-defined Northeast Corridor infrastructure characteristics (vertical profile, horizontal alignment, maximum authorized speeds, civil speed restrictions, and station stop locations).

Particular attention was devoted to accurate aerodynamic resistance modeling, especially at higher velocities where traditional methodologies are known to overstate aerodynamic resistance.

TPC results were provided to the Amtrak “task teams” responsible for proposal review.  Technical discussions between these task teams and proposers led to iterative changes in trainset design concepts.  Additional TPC simulations were performed as necessary to address these design changes and determine if carbuilder technical proposals were consistent with Amtrak’s requirements.  

Ultimately, the final TPC runs developed through this process were verified by Amtrak Transportation Planning personnel.  TPC data and results were then placed in escrow by Amtrak counsel as enforceable measures of performance under the contract with the selected carbuilder.

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NJ Transit

NEC Middle Zone Train Performance/Signal Capacity Analysis

Newark, New Jersey

Working with NJ TRANSIT Rail Service Planning and Equipment Engineering, LTK is assisting the railroad in quantifying capacity differences between existing Jersey Arrow III Electric Multiple Unit (EMU) and ALP-46 push-pull consist with multi-level coaches.  This analysis focuses on the critical “Middle Zone” segment between Midway and Union Interlockings on the Northeast Corridor (NEC). LTK is also assisting NJ TRANSIT in quantifying various levels of potential signal system upgrades in this segment that would mitigate any losses in capacity due to train performance as part of support of overall strategic fleet expansion plans.

OS4-NJTMiddleNJ TRANSIT’s RAILSIM database was used to compare morning peak hour Middle Zone capacity under current fleet assignments versus replacement of the Jersey Arrow III portion of the fleet with ALP-46 and Multi-Level coaches (and using dual ALP-46 locomotives for longer trains).  The analysis shows that the current morning peak hour schedule for Track 1 operation in the Middle Zone exceeds the practical capacity of the signal system.  With maximum train lengths already operated in this segment, NJ TRANSIT serves the high ridership between Jersey Avenue and Metropark through operation of peak period trains at reduced speeds to optimize throughput.

Depending on the train consist, stopping pattern and routing, the most constraining Middle Zone signals can be found at County Interlocking or at Lincoln Interlocking, with Clear (green) signal clearing times in the range of 8 to 9 minutes.  These clearing times are unusually long because the signal system is designed for 90 to 110 mph maximum train speed and there are multiple closely-spaced stations.

Working with Amtrak, NJ TRANSIT is pursuing resignaling of this territory using additional cab signal aspects to improve capacity.  The current signal installation does not include any cab signal aspects between Approach Medium (120 code, or 45 mph) and maximum authorized speed (90 to 110 mph, depending on location) whereas new designs will support intermediate 60 and/or 80 mph cab signal aspects.

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Santa Clara Valley Transportation Authority (VTA)

Rail System Analysis

Santa Clara County, California

Santa Clara Valley Transportation Authority (VTA) provides bus and light rail transit service within Santa Clara County, located at the south end of San Francisco Bay.  The 42-mile light rail system serves the central business district and civic center of San Jose, the residential areas to the south and east, and the “Silicone Valley” technology campuses to the north.  Its five corridors include exclusive rights-of-way in freeway median, operation in transit mall and local street median governed by traffic signals, and four sections of single track.  Three service lines provide links to VTA bus lines and employer shuttles, and connections with Caltrain, Altamont Commuter Express (ACE) and the Amtrak Capitol Corridor regional rail services.  Future connections will be provided to the planned BART extension into San Jose. 

OS5-SanJoseVTAIn 2008, VTA requested proposals for professional services to perform a comprehensive operations analysis of its light rail system.  LTK, as part of a larger consulting team, was selected to manage this effort following a highly-competitive selection process. 

The objective of the study is to recommend a strategy that is two-fold:

  • Improve the efficiency and effectiveness of the existing service, by attracting more ridership while controlling operating costs, and.
  • Position the system to provide the service capacity necessary to meet projected increases in demand through 2035.

The scope of the study includes a restructuring of the existing services as well as moderate capital improvements.  Service considerations include the addition of express and skip-stop services, rearrangement of service patterns and the closure of lowest-ridership stations, all with the objective of improving the travel times for the majority of riders.  Capital improvements include: double-tracking the single-tracked sections, relocating one station to improve the transfer to regional rail, and right-of-way improvements to enable trains to operate at higher speeds in the downtown mall, in-street and along the freeway.  Two line extensions, one new station and grade separation at key locations are also being examined. 

Ten system scenarios have been defined for analysis, based on inputs from the VTA Operations, Planning, and Construction departments and the BART Silicon Valley Rapid Transit Corridor (SVRT) project, as well as the results of a preliminary analysis of travel demand in the service area.  Service and operating plans for each scenario were then developed, including yard put-ins, yard lay-ups, equipment cycling and detailed train schedules.  Using sophisticated simulation software, LTK then calculated run times for each service and identified any operational constraints that may occur due to express and local service co-location, or conflicts at merge points, intersections and junctions.  The resulting travel times are being used to forecast ridership for each scenario.

Three of the most promising ten scenarios will be selected by VTA for further analysis.  Capital costs and annual operations and maintenance costs will be estimated, along with the development of a financial risk analysis.  Additional network simulations will be performed to more closely examine service coordination and scenario modifications.

Throughout the project, the consultant team has held a number of workshops with VTA management and staff from stakeholders departments to discuss, refine and select the scenarios for further study.  This has proven to be very effective in guiding the project, providing a forum for open discussion of agency objectives and requirements, feedback on early task findings and recommendations, and direction on future tasks. 

In addition to overall project management, LTK’s work products include simulation model results, operations and maintenance costing at various projected levels of service, operations analysis and evaluation of the adequacy of infrastructure, capacity analysis of the light rail fleet, and an evaluation of technical requirements to raise maximum speeds from 55 mph to 65 mph. 

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New York State Department of Transportation (NYSDOT)

High Speed Rail Operating Plan Development and Simulation

Albany, New York

LTK is supporting NYSDOT in its ambitious plans for High Speed Rail on the Empire Corridor between New York, Albany-Rensselaer, Buffalo and Niagara Falls. Focusing on the segment from Albany-Rensselaer to Buffalo-Depew, LTK worked with NYSDOT and Amtrak to develop computer simulation models of travel time improvements in the Corridor and to apply these improved travel times to future Operating Plans. LTK created two future “visions” of Empire Corridor rail operations, reflecting 2018 and 2030 train volumes.

OS6-NYSCOTThese future operating plans feature:

  • Hourly frequencies between Albany-Rensselaer and New York for most hours of the day,
  • Early morning westbound Empire Corridor service from Albany-Rensselaer,
  • Additional frequencies to and from Saratoga Springs, supporting potential commuter traffic to/from Albany-Rensselaer,
  • A daily train to the Finger Lakes Region gateway of Geneva, via Syracuse,
  • A daily train between New York and Cleveland, providing additional frequencies and daytime service to many stations served by the Lake Shore Limited,
  • Enhanced service to Niagara Falls.

The future operating plans assume extensive new sections of third mainline track in the Empire West Corridor, capable of supporting speeds of up to 110 MPH. CSX is assumed to continue to dispatch all of the trackage. The extensive third track initiative also includes some sections of fourth track for higher speed passenger train “meets” and will also likely require the use of existing tracks by passenger trains in some segments of the Corridor.

The future operating scenarios assume that there will be at least two platform edges available for simultaneous dwells at Syracuse, Rochester and Buffalo-Depew. In addition, the future operating scenarios assume capacity improvements between Albany-Rensselaer and Schenectady, in the form of full double track. LTK computed future operating cost metrics, such as crew-hours and train-miles, as well as a complete set of equipment cycles that were used to predict future locomotive and coach fleet requirements.

The computer simulation models show that the third mainline track (with critical passing capability in the form of some sections of fourth mainline track) can reduce trip times by about an hour from those presently scheduled. This represents a reduction of nearly two hours when compared to a recent statistical sampling of Amtrak’s average “over the road” travel times in the Corridor.

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