1. Ohio Traffic Forecasting Manual
Module 3: Part III Exercises

2. Model Refinement

3. Model Refining Exercises
Coding a New Project
Intersection Coding
Splitting a Zone
Coding a Special Generator
Ohio Traffic Forecasting Manual

4. Project : Coding a New Road
Upgrade Robb Ave west of Cole Rd
4-lane urban arterial with posted speed of 45 mph
Add dedicated left turn lanes at the specified intersection
Remove current prohibitors at Cole Rd and Robb Ave
Prohibit left turns on Cole Rd at Robb Ave
Ohio Traffic Forecasting Manual

5. Coding a New Scenario
Create a child scenario under Base called Robb_mod (right click on Base in the scenario panel, Add Child)
Type in a description
Will need to update the six main model run Input Files:
Network file
Turn Penalty / Prohibitor file
Junction files (AM, MD, PM, EV)
Ohio Traffic Forecasting Manual

6. Editing New Input Files
Find the project area using road names (and/or referenced zone numbers)
Which links and nodes will be affected?
Need to know if any transit lines or prohibitor files will be affected
Suggested to start with copies of files for the network, turn prohibitors, and transit lines
Ohio Traffic Forecasting Manual

7. Editing New Input Files
Open the new network (Data pane \ lim10G.net)
Use Layer Control on Home tab \ Network Layers to:
Add the TAZ boundary layer (shape file) found in the INPUTS directory: limtaz10nad83_april2013mods.shp
Add the copied Transit Line layer from the new directory: lim10B.LIN (don’t replace node)
Load the copied Turn Prohibitor file from the new directory
Intersections tab \ Turn Penalty File
Lim10Gpro_Robb.pen (copy of Lim10Gpro.pen)
Ohio Traffic Forecasting Manual

8. Editing New Input Files
Display the turn prohibitor locations using Node Coloring. Home tab\ Post Node \ Color
Make the color and size distinguishable
Criteria: _NUMPROH>0
Can right click in the criteria area to see a list of available variables
Close
Node 2397 should be identified as having at least 1 prohibitor
Display the transit lines if not visible
Post Transit\Display Lines(s)
Select All
Ohio Traffic Forecasting Manual

9. Editing New Input Files
Select the link for the Robb Ave upgrade
Select the link ( )
Change necessary link attributes
POSTSPD
LANES
WIDTH
TURNLANE
Transit line files are changed automatically if they use modified network links
Add stop nodes
In the Transit Line Manager, save the modified (mod) transit file
Ohio Traffic Forecasting Manual

10. Intersection Coding
On links, TURNLANE and IXTPYE values are the attributes that are most likely to be different on opposite sides of a 2-way link
Use the 5-digit TURNLANE codes
Left only, Left-Thru, Thru, Right-Thru, Right only
Other intersection data can be reviewed in the Input Intersection Data File (*.IND file) which is created by running the network calculators
Run the net calculators application using the new network and prohibitor files for inputs
Ohio Traffic Forecasting Manual

11. Link Attributes
Once the new roadways are included in the network, their attributes should be corrected as necessary:
POSTSPD (Posted speed limit)
FACTYPE (Facility type: Freeway, Arterial, etc.)
AREATYPE (Area type: CBD, Urban, Suburban, Rural)
LANES (Number of through lanes)
WIDTH (Directional roadway width)
IXTYPE (Intersection control type; signal, stop sign etc.)
TURNLANE (Intersection turn lanes)
Be sure to also correct links that may have been split
Ohio Traffic Forecasting Manual

12. Intersection Turn Prohibitors
New scenario is to have all left turns allowed
To see coded prohibitors, select node 2397
Intersections tab \ Turn Penalties…
Values of -1 indicate prohibitors
Start with a copy of the old file
Add or delete those values and Save
Ohio Traffic Forecasting Manual

13. Network Calculator Application
On the Applications (APP) panel, select: NET_CALCULATORS
Double-click scenario (Robb_mod)
Fill in filenames for new input and output files
<Run>
Ohio Traffic Forecasting Manual

14. Intersection Coding
With the network open, load in the intersection file: Intersection \ Input Data File (lim10G_NT.ind)
Post the intersection locations
Signal, 2-Way Stop, All-Way Stop, uncontrolled
Ohio Traffic Forecasting Manual

15. Alternative Intersection Coding
Show input intersection data
Ability to View (or modify) the intersection data
Two-Way stop has only simple geometry
All-Way Stop and Signals have graphical lane representation
Signals also have timings and phasing
Ohio Traffic Forecasting Manual

16. Alternative Intersection Coding
View intersection node 2293
Check the graphics against the expected geometry
Network changes can be done here, but safer to do this by coding link attributes
Cannot save log files
Ohio Traffic Forecasting Manual

17. Alternative Intersection Coding
Save the data in the Intersection Data Editor
The new file is saved, and the old file is saved as a copy with *.old appended
Both are text files that can be manually edited
Cut and paste data for the updated node only into a new text file
This file now can be used as the Intersection Override File in the network calculators
Ohio Traffic Forecasting Manual

18. Assignment Results
Base Upgrade
Ohio Traffic Forecasting Manual

19. Splitting a Zone Zone 119 needs to be split into two as shown
Additional centroid node and centroid connectors
Change zonal data file
Possibly make changes to other links in the network
Ohio Traffic Forecasting Manual

20. Splitting a Zone
Get a new centroid node from the dummy nodes in the network (these are grouped in the southern part of this network)
Nodes are available, but use 396 to keep zones consecutive
Find the node and move it into the area, and delete its centroid connectors
Place nodes 119 and 396 into the center of activity of the new zones
Ohio Traffic Forecasting Manual

21. Splitting a Zone
Make sure that the Maximum Internal Zone Number is changed in the Main Model Run Options
Ohio Traffic Forecasting Manual

22. Splitting a Zone
Connect the centroids to the network as shown (one split link needed)
Make the change in the standard model setup
Update the boundary shapefile with other GIS software
Ohio Traffic Forecasting Manual

23. Splitting a Zone
For this exercise, distribute 20% of all independent variable data file into the new zone
Do not divide values for:
MED_HHINCO, AVG_PARK, TERM_TIME
Check the special generators for zone 119
Better refinement would examine actual locations of households, businesses, etc.
Output to a new DBF file
Ohio Traffic Forecasting Manual

24. Splitting a Zone / ASN Only
Can use a MATRIX renumbering script if only running assignment
A copy of this script is in the Inputs folder
Ohio Traffic Forecasting Manual

25. Coding a Special Generator
The changes in trips due to special generators are defined by trip purpose and one of three method types
The methods and their codes are
10; Factor adjustment
20, Difference
30, Factor replacement
31, Factor replacement for IE trips
Ohio Traffic Forecasting Manual

26. Coding a Special Generator
Trip Purpose Types:
1 IE Work
2 IE Non-work
3 IE Truck
4 Heavy Truck
5 Commercial Truck
6 Home-based work
7 Home-based shopping
8 Home-based school
9 Home-based other
10 Non home-based work
11 Non home-based other
12 Visiting
Ohio Traffic Forecasting Manual

27. Coding a Special Generator
The University of Toledo is putting in a branch campus to compete with University of Northwestern Ohio (in zone 199)
The campus is being built near the new interchange at US 30 and SR 115 in zone 25, so all of the trips are coming from outside of the model area
Assume that the additional trips created by this is similar to the UNO campus
Update the special generator file:
limSPECGEN10.csv
Ohio Traffic Forecasting Manual