The TRANSIMS Model: Combining Travel Demand and Microsimulation Operating Paradigms Presented to 2012 ITE District 6 Annual Meeting by John Kerenyi, P.E., Senior Engineer, City of Moreno Valley June 26, 2012
Summary of Presentation What is TRANSIMS How are travel demand and microsimulation combined Selected results from Heacock Street extension study (new street connection) Current status of TRANSIMS software Prospects for future use of dataset
TRANSIMS Overview Seeks to incorporate additional detail into the traffic forecasting process – –Movement of individual vehicles – –Intersection controls e.g. traffic signal operation, gap acceptance at unsignalized locations
Trip Conversion Process TRANSIMS is an activity-based model; however, development of a robust activity modeler is suspended pending better data to operate on As a result, the travel information TRANSIMS currently operates on is typically imported from a four-step model (in this case, RivTAM, which is based on the current SCAG model)
SCAG Region 40 million daily base-year trips 50 million daily trips in 2035
Microsimulated Subarea 1 million daily base-year trips 2 million daily trips in 2035 Microsimulating the MPO’s Model means: Consistency Defensibility Added detail, e.g. Intersection control delay Time-of-day data
Typical Simulation Flowchart Convert Network Convert Trip Tables Load Network Run Router Shuffle Plans Seek System-Optimal Solution Test Router- Derived Plans Run Microsimulator Stabilize Microsimulation Seek User-Optimal Solution Establish Intersection Controls BPR Formula Driven Microsimulator Delay Driven Set Up One CPU Four Hours 48 CPUs Five Days 24 CPUs One Week 8 CPUs One Day
TAZ’s vs. Activity Locations
Commercial/Residential Traffic
Box Springs/Freeway Interaction
Freeway/Surface Street Diversion
Eucalyptus TOD Traffic Prediction
Time Of Day Flows—Example TRANSIMSGround Count
Heacock Street Extension
ADT Comparison Red: Base network Blue: Alternative network
ADT Comparison Red: Base network Blue: Alternative network
Heacock Street Users (AM) Red: Base network Blue: Alternative network
Heacock Street Users (PM) Red: Base network Blue: Alternative network
Perris Blvd Users (AM) Red: Base network Blue: Alternative network
Perris Blvd Users (PM) Red: Base network Blue: Alternative network
Shifted to Perris (AM) Red: Base network Blue: Alternative network
Shifted to Perris (PM) Red: Base network Blue: Alternative network
TRANSIMS Program Status Moreno Valley TRANSIMS uses Version 4, which is stable Version 5 is actively under development; focuses on better integration between tools TRANSIMS is open-source; FWHA pays AECOM to write the code, which is freely shared For more information visit
New TRANSIMS GUI
New TRANSIMS Visualizer
Potential Applications of SCAG/RIVTAM Dataset Link addition/deletion/change Major project construction detours Operational enhancements e.g. intersection controls, lane augmentation, signal operation improvements Any application requiring refined time-of-day analysis Rigor of four-step model with detail of microsim
Acknowledgements Carleton Waters of Urban Crossroads served as advisor and his staff provided the trip table alternatives by running TransCAD/RivTAM Mike Ainsworth from SCAG lent input and support to the FHWA proposal and attended every TRC meeting, lending further valuable input James Camarillo and Maria Aranguiz from Caltrans District 8 attended TRC meetings regularly
Questions?
Perris Blvd Speed Differentials (AM)
Perris Blvd Speed Differentials (PM)
SCAG Region
Histograms
PM Impacted Intersections
Top 10 AM Link Delay Changes
Top 10 PM Link Delay Changes
Subregion
Commercial/Residential Traffic
Turning Movement Validation AMPM
Microsimulator Outputs Base Land Use ScenarioAlternate Land Use Scenario
AM Peak-Hour Intersection Delays
PM Peak-Hour Intersection Delays
Traffic Index Increases
Travel Times Between Industrial Zones
Truck Volume Differential (Daily)
Truck Volume Differential (Night)
Selected Freeway Operations Results