0. Tips, Trips, and Traps of TransCAD Modeling
LSA Associates, Inc.
September 2001
North Carolina MPO Conference

1. Agenda Why Model? Why Jurisdictions Convert to TransCAD?
The Transportation Model
GIS Developer’s Kit
Applications

2. Why do we model the transportation network?
Why Model?
Why do we model the transportation network?

3. Why Model?
To consider the effects of land use, transportation, and air quality
To determine infrastructure needs, costs, and timing as growth occurs
To analyze land use and transportation alternatives
To provide a consistent platform for travel forecasting
Required by the federal government for metropolitan areas

4. The History of Travel Forecasting
Aggregate Models
Few zones
Major highway planning only
Computers available to large agencies
50’s
Computer chip technology advances
Federal government sponsorship
Travel behavior surveys widespread
Basic transit capability
60’s and 70’s
80’s and 90’s
Shift to microcomputers
More zones
Detailed transit and HOV models
Windows-based
More disaggregation and detail
GIS-based models
Microsimulation
00’s

5. Why Jurisdictions Convert to TransCAD?
Why are agencies converting their travel models to TransCAD?

6. Why Convert?
Some widely-used older modeling software are no longer being supported – a new modeling platform is required
Limited capabilities in
Graphics
Memory
GIS
Network size
Number of TAZs

7. There are many states in America that currently use TransCAD
TransCAD Users
There are many states in America that currently use TransCAD
Many states in America are using TransCAD. Some are just beginning, some have full running models. This map is not an exhaustive list.

8. Geographic Information Systems
A GIS-based transportation model
Compatible with other GIS tools
Spatial Analysis
ArcView
Shape Files
TransCAD
*.dbd Files

9. Why TransCAD?
A powerful modeling software that can enhance the modeling process
Windows-based menus that are intuitive to manipulate
A GIS software with transportation modeling capabilities
No internal size limitations
Scenario manager for easy file management
Ability to easily analyze intermediate results
Mapping and visualization tools designed for GIS and transportation applications
TIP: Choose a powerful computer!

10. The Transportation Model
What is involved with a travel demand model?

11. Modeling Process Trip Generation Trip Distribution Mode Analysis
Traffic Assignment
Socioeconomic Data
Roadway Network
Transit Network
Transit Ridership
Transit Assignment
Roadway Volumes
Performance Report
How many trips?
Where will they go?
What mode?
What route?
Identify needs
Alternatives analysis
Ask the questions…

12. TransCAD Inputs Easy to understand file structure
No restrictions on file names, locations, etc.
File names are easy to change in the model structure with the scenario manager, created in GISDK
Working with TransCAD is very flexible and easy to understand. The scenario manager is a key.

13. TransCAD Outputs
Checking intermediate modeling results is easy in TransCAD
Identifying results from an individual project area allows detailed study of the project
Performance module allows consistent reporting of results

14. Data and Databases Geographic data Network data Attribute data
TransCAD model data
Socioeconomic data
US Census data
Jurisdictional boundaries
Zip codes
Railroads
Water Features
Tiger Streets Files

15. AVI – Opens up the Lake Elsinore model dialog box
AVI – Opens up the Lake Elsinore model dialog box. This dialog box runs the entire model from start to finish with one click of the button.

16. AVI – An example of a scenario manager
AVI – An example of a scenario manager. This is used to manage all model alternatives with the file names and a few parameters.

17. Networks Networks are GIS databases
Conflation to GIS distances and shapes
Foundation for traffic counts, performance, transit, and any other data
Multi-year network capability
TIP: Keep raw count data and adjustments in traffic count database

18. Project Selection (TIP/RTP)
Networks
GIS Networks
Roadway System
Transit Routes
Air Quality
Performance
Time of Day Volumes
Project Selection (TIP/RTP)
Traffic Counts

19. AVI – There is a LOT of information stored within the network
AVI – There is a LOT of information stored within the network. This avi shows the info tool and how the user can add data, change data, etc. The network includes a place for Accidents, Bicycle Information, etc.

20. AVI – This movie shows two conflation examples as well as a copy/paste example. The thin yellow lines are the city centerline streets, the thick lines are the model roadway network, color coded by facility type (the dotted green lines are centroid connectors). Most jurisdictions have current centerline files, and if not, TIGER files are available for the entire United States.

21. Traffic Analysis Zone Data
Zonal areas used in modeling trips
Ability to incorporate census data
Used for summaries and reports
Used for visually verifying data

22. Socioeconomic Data Interface with popular GIS platforms
Land use to socioeconomic conversion using TransCAD’s GIS tools
Visual representation of land use and socioeconomic data
TAZ coverage provides foundation for area- based data and is easily modified
TIP: Socioeconomic sub-model can use a Fratar process coded in GISDK

23. Socioeconomic Data and TAZ Structure
GIS TAZ Structure
Area Type
2020 Socioeconomic Data
Performance and Air Quality
Area based Indexes
K Factors
Terminal Penalties
1998 Socioeconomic Data

24. AVI – This shows a color map of household density
AVI – This shows a color map of household density. This is useful in verifying and correcting input data.

25. Trip Generation Robust cross classification production model
Unlimited trip purposes
Production allocation and attraction allocation models
TIP: Include all modeling steps in TransCAD using GISDK, without compromising model structure. This ensures a full running model from start to finish.

26. Trip Generation Incorporate land use data Detailed trip purposes
Distance-based allocation models
Special generators
Universities
Hospitals
Amusement parks
Event centers
Malls
Government installations

27. AVI – this shows a dot-density of different land use acreages in Lake Elsinore.

28. Trip Distribution
TIP: Geocode survey data in house to determine trip lengths
Desire lines between TAZs and districts
TRIP: GISDK standard gravity evaluation procedure does not correctly apply K factors in version 3.6
Friction factors – calibrated curves versus lookup table

29. Mode Analysis Customized nested logit and multinomial logit models
TIP: Don’t be limited to standard TransCAD procedures, create exactly what you want with GISDK
Distance-based bike and pedestrian equations

30. Nested Logit Structure
Person Trips
Motorized
Non-Motorized
Drive Alone
Shared Ride
Auto Passenger
Transit
DA Non Toll
DA Toll
SR2 Non HOV
SR2 HOV
SR3 Non HOV
SR3 HOV
Auto Express
Auto Local
Walk Express
Walk Local
Non HOV Non Toll
Non HOV Toll
Express
Urban Rail
Commuter Rail
Non HOV Non Toll
Non HOV Toll
HOV Non Toll
HOV Toll
Express
Urban Rail
Commuter Rail
HOV Non Toll
HOV Toll

31. Traffic Assignment Time of day User defined volume-delay equations
Speed post-processing
Speed feedback
AM peak – congested speeds
Off peak – freeflow speeds
All or nothing, capacity constrained assignments with comparison

32. TransCAD Transit Capabilities
Walk access vs drive access
Unlimited number of modes
Unlimited number of variables
Stops dependent upon individual routes

33. Transit Assignment Transit boardings by stop, by route, or by mode
Drive or walk access assignment
Transit flows by link
Transit line volumes

34. Validation Screenlines – GIS line layer created quickly
TRIP: One way links confuse the built-in screenline analysis functions

35. AVI – This shows a map with volume bandwidth
AVI – This shows a map with volume bandwidth. The movie displays the screenlines.

36. Model Conversion Process
Existing Model
TRIP: The base converted model is not ready to go!
TIP: Develop performance reporting capabilities early.
TRIP: TransCAD uses different distances – this may affect model results.
TRIP: Need to adjust for software differences.
Initial Model Conversion
(Caliper or LSA)
Network Conflation and Model Replication
Performance Reporting
Model Enhancements
Calibration / Validation

37. The endless possibilities with the TransCAD programming language
GIS Developer’s Kit
The endless possibilities with the TransCAD programming language

38. TransCAD Scripting Capability
GISDK is the TransCAD programming language
Allows for complete automation of the modeling process unique to each model
Eliminates user error by programming all steps and variables in a model run
Similar to programming in C++ (with different syntax and commands)
Use the programming editor of your choice to create and edit the GISDK script
TIP: Boxer Software is a good (and inexpensive) programming editor
GISDK is a very important tool when using TransCAD for running models. With GISDK, everything is programmed to do the exact same thing with the same variables each time it is run. File names can change easily within a scenario manager to create a new model run.

39. Model User Interface The dialog boxes that run the whole model
Reduce errors by eliminating point/click/type commands
GISDK is the key to programming the model
One option to run the model is to go through the menus and use standard TransCAD procedures manually. This can produce many errors and can easily have consistency errors. The best option is to run the model through a dialog box such as this one. Every model run will perform the exact same procedures in the same order with the same parameters! These provide consistency between model users, so more than one person/department can correctly run models.

40. TransCAD Dialog Boxes Custom user interfaces created using GISDK
Fully automates the model procedures – including file names, variables, and summary reports
TIP: These really help the consistency and accuracy of the model!
Dialog boxes created with GISDK allow a user friendly environment to run the models.

41. Scenario Manager Created using GISDK
Manages all files related to each alternative
An example of the Mason Street model scenario manager. All input and output files are chosen with this dialog box. It uses typical Windows file open and file save as dialog boxes to find the correct files. Since file names can be named in a logical manner, it is easy to find the correct files.

42. GIS Developer’s Kit (GISDK)
Program exactly what we want TransCAD to do
Allows for any mathematically sound method or procedure
Not confined to standard TransCAD procedures
Full dialog box customization
Scripting allows for full customization.

43. Performance Reporting
The possibilities available for performance reporting

44. Performance Module Provides consistent and convenient summary reports
Created with GISDK
Customized to the client’s needs
Analysis tool for troubleshooting model runs
Facilitates calibration and validation
TIP: Create EARLY in modeling process!
A VERY important step!

45. Summary Reports
The summaries are customized using GISDK and summarize the model data in many ways, including…
Facility Type and Area Type
Capacity Analysis
Congestion Delay
Air Quality Emissions Results
Summary reports allow the data to be summarized in the same way for each model run. This gives a great comparison tool between several model runs. You can be assured that the reports are summarizing the data in the exact same way – no place for user error.

46. Applications
TransCAD applications for the transportation planning and analysis process

47. Land Use and TAZ Overlay
Land Use Map
Land Use and TAZ Overlay
TAZ Map

48. I-25 Socioeconomic Data Analysis
Land Use Data

49. I-25 Corridor Analysis
1998 Data
2020 Data
Land Use Data

50. Supply and Demand Analysis
Difference

51. Colorado Springs Alternatives Analysis

52. Buffer Analysis
Mile Buffer Travel Time Buffers

53. Traffic Impact Analysis
Trip Distribution for a proposed development

54. Traffic Impact Analysis

55. Site Selection / Geocoding
Fire stations
School sites
Park locations
AVI – This is a geocoding example from Poudre High School. There were no zip codes available in the data, but we can just use the city to locate the addresses. TransCAD is very flexible in the way it geocodes.

56. Site Selection / Geocoding

57. Travel Sheds / Critical Link Analysis
Identify users of a specific facility
Analysis for Adequate Community Facilities Ordinances and road fee programs

58. GIS-Based Transportation Improvement Programs
Agency
Project
Funding Amount
Anaheim
Lincoln Avenue Signal Coordination
$52,910
State College SR-91
$150,000
Buena Park
Artesia 1-5 Interchange
$132,795
Costa Mesa
Fairview Road
$29,846
Irvine
Bicycle Program
$67,200

59. Transit Planning and Operations
Strategic transit planning
University transportation planning
Corridor planning
Market identification and productivity
Management and placement of capital assets

60. Land Use / Transportation / Air Quality
Conceptual level analysis of LUTRAQ relationship
Comprehensive plan updates
Triggers – population vs. VMT growth
Air quality and emissions inventory
Stationary and mobile sources
On-road mobile emissions estimation
Mobile5
Nonattainment area
Energy and fuel consumption

61. Air Quality Analysis Link-based emissions
Zone-based emissions (i.e. cold starts, evaporate VOCs, etc.)
Air quality conformity determinations
Redesignation and classification issues
Integration with gridded urban airshed modeling
Integration with Mobile5

62. Land Use / Transportation / Air Quality
Available from the performance summary report for the Fort Collins Nonattainment area

63. Integrated Air Quality Modeling
TransCAD Travel Demand Model
(speeds, vehicle miles of travel, time of day, …)
EPA Mobile/Part Emissions Models
(temperatures, fuel characteristics, emission factors, …)
Emissions from On-Road Vehicles

64. GIS-Based Emissions Inventories
Link-based emissions
Gridded Overlay for Region
Zone-based emissions

65. Intersection Analysis
Intersection Flow Diagram Volumes from TransCAD
Traffic Counts
NCHRP 255 Process
Synchro Intersection Analysis
There has always been a concern about getting future intersection levels of service from a link based travel demand forecasting model. We have created an add-in for TransCAD which expedites getting the intersection levels of service into 3d animation.
SimTraffic 2D Animation
VISSIM 3D Animation

66. TransCAD Turn Movement Forecasts

67. AVI – a short video with the Turn movements program

68. SimTraffic Micro-Simulation

69. VISSIM Micro-Simulation

70. VISSIM Micro-Simulation

71. VISSIM Micro-Simulation

72. VISSIM Micro-Simulation

73. VISSIM Micro-Simulation

74. VISSIM Micro-Simulation

75. VISSIM Micro-Simulation

76. VISSIM Micro-Simulation

77. Construction Management
Modify signal timing in response to construction closures

78. Future TransCAD Applications
Interactive MPO Project Prioritization and Funding Allocations
Traffic Impact Studies: Cumulative improvements and impacts, time of day project distributions
FHWA TDM Model
Mixed Use Activity Center Trip Generation & Distribution
Bicycle Assignments
Transportation Corridors
Pavement Management

79. LSA Associates, Inc. 132 West Mountain Avenue Fort Collins, CO 80524
The ending slide

80. Tips, Trips, and Traps of TransCAD Modeling
Presented by LSA Associates, Inc.
September 2001
North Carolina MPO Conference
Fayetteville, NC