Implementing the FHWA Quick Response Freight Model in the Twin Cities Steve Wilson and Jonathan...
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Transcript of Implementing the FHWA Quick Response Freight Model in the Twin Cities Steve Wilson and Jonathan...
Implementing the FHWA Implementing the FHWA Quick Response Freight Quick Response Freight Model in the Twin CitiesModel in the Twin Cities
Steve Wilson and Jonathan EhrlichSteve Wilson and Jonathan Ehrlich SRF Consulting Group, Inc.SRF Consulting Group, Inc.
Dan BeaganDan BeaganCambridge Systematics, Inc.Cambridge Systematics, Inc.
Presented to Tenth Transportation Research BoardPresented to Tenth Transportation Research Board Planning Applications ConferencePlanning Applications Conference
Twin Cities Regional Twin Cities Regional Freight Planning ModelFreight Planning Model
ObjectivesObjectives
Approach/MethodologyApproach/Methodology
Calibration ConsiderationsCalibration Considerations
ApplicationsApplications
Objectives of the ProjectObjectives of the Project
Improve New Regional Travel Improve New Regional Travel Demand ModelsDemand Models
Better Reflect Impact of Trucks on Better Reflect Impact of Trucks on Traffic FlowTraffic Flow
Lay Groundwork for Multimodal Lay Groundwork for Multimodal Freight Analysis and ModelingFreight Analysis and Modeling
Connect to Statewide Freight PlanConnect to Statewide Freight Plan
ApproachApproach
Based on FHWA Based on FHWA Quick Quick Response Freight Response Freight ManualManual (1996) (1996)
Make use of local Make use of local datadata
Make use of limited Make use of limited resourcesresources
Zonal DataZonal Data
• Employment Employment Categories:Categories:
Agriculture, Mining, Agriculture, Mining, ConstructionConstruction
Manufacturing, Manufacturing, Transportation, Transportation, Communication, Communication, Utilities, Wholesale Utilities, Wholesale TradeTrade
Retail TradeRetail Trade Office and ServicesOffice and Services
Zonal DataZonal Data
Employment Employment DataData• Census vs. Census vs.
ES202ES202 Freight Facility Freight Facility
InventoryInventory• Quality Control Quality Control
IssuesIssues
Network DataNetwork Data
HighwaysHighways• ProhibitionsProhibitions• GradeGrade• Vehicle Classification CountsVehicle Classification Counts
Navigable WaterwaysNavigable Waterways• Terminal LocationsTerminal Locations• Locks and DamsLocks and Dams
RailwaysRailways • At-Grade CrossingsAt-Grade Crossings• Intermodal TerminalsIntermodal Terminals
Other DataOther Data
Freight Analysis FrameworkFreight Analysis Framework• National Freight Flow DatabaseNational Freight Flow Database• Growth Rates for External TripsGrowth Rates for External Trips
External Origin-Destination External Origin-Destination SurveySurvey• Distribution of External TripsDistribution of External Trips
Other DataOther Data
Light Commercial VehiclesLight Commercial Vehicles• In the regional model (large portion of In the regional model (large portion of
NHBW trips)NHBW trips)• Difficult to quantify either in vehicle Difficult to quantify either in vehicle
classification counts or in home-classification counts or in home-interview surveysinterview surveys
• MnDOTMnDOT Light Commercial Vehicle Light Commercial Vehicle Study,Study, 1999 1999
Four Step Model: Trip Four Step Model: Trip GenerationGeneration
By Vehicle Classification from By Vehicle Classification from QRFMQRFM• Single UnitSingle Unit• CombinationCombination• ‘‘Light Commercial’Light Commercial’
Function of Employment TypeFunction of Employment Type External Trips based on External External Trips based on External
Station Vehicle ClassificationStation Vehicle Classification Special Generator CapabilitySpecial Generator Capability
Four Step Model: Trip Four Step Model: Trip DistributionDistribution
Default gravity model friction factor Default gravity model friction factor curves from curves from QRFMQRFM
Modify trip table using matrix Modify trip table using matrix estimation estimation
Adjusted default curves based on Adjusted default curves based on estimated matrixestimated matrix
Figure 3: Single Unit Truck Trip Length Distribution
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1
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3
4
5
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0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75
Off-Peak Congested Travel Tim e
Per
cen
t o
f T
rip
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Estimated Distribution Model
Four Step Model: Time of Four Step Model: Time of DayDay
Matches 24 time Matches 24 time periods from periods from Regional ModelRegional Model
Constant factors for Constant factors for each time period for each time period for each vehicle each vehicle classificationclassification
Based on 24-hour Based on 24-hour vehicle classification vehicle classification count datacount data
Four Step Model: Four Step Model: AssignmentAssignment
Regional Model AssignmentRegional Model Assignment• Equilibrium AssignmentEquilibrium Assignment• 24 Time Periods24 Time Periods
Five Assignment PurposesFive Assignment Purposes• SOV, LCV, HOV, SU, CMBSOV, LCV, HOV, SU, CMB
Three PathsThree Paths• SOV/LCV, HOV, TruckSOV/LCV, HOV, Truck
Passenger Car EquivalencyPassenger Car Equivalency
ValidationValidation
Highway Link VolumesHighway Link Volumes
VMTVMT
Calibration ConsiderationsCalibration Considerations
Data AvailabilityData Availability• Vehicle ClassificationVehicle Classification• Internal Origin-DestinationInternal Origin-Destination• Trip Length DistributionTrip Length Distribution• External Station DataExternal Station Data• Commodity DataCommodity Data
Concurrent Regional Model Concurrent Regional Model CalibrationCalibration
Regional ScopeRegional Scope
ApplicationsApplications
Forecasting Truck TrafficForecasting Truck Traffic• Pavement DesignPavement Design• Development ImpactsDevelopment Impacts
System Level ResponsesSystem Level Responses• Modal Shift Impacts Modal Shift Impacts • Value of Time/Benefit-CostValue of Time/Benefit-Cost
Truck Impacts on CongestionTruck Impacts on Congestion Grade Crossing AnalysisGrade Crossing Analysis
Recommendations for Further Recommendations for Further ImprovementImprovement
Commercial Vehicle Tracking SurveyCommercial Vehicle Tracking Survey
National/Multi-State Commodity Flow National/Multi-State Commodity Flow ModelModel
External Truck Intercept SurveyExternal Truck Intercept Survey
Vehicle Classification DataVehicle Classification Data
Questions?Questions?