HighwayNetworkCoding_Old

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Saving this as archive to HighwayNetworkCoding_Old for reference. -lmz 2018/20/17

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The MTC highway network is coded and maintained as a comprehensive highway network file, commonly referred to as the master highway network. The file consists of network links that represent the roadways. A project highway network file is developed in three stages from the master highway network file. It consists of roadway links classified by functional class, zone connector links, and a few other additional links to support transit modeling. A project-specific highway network is developed as follows:

1. Start with the master network file
2. Create a new project in the master highway network
3. Extract a project specific (base) highway network from the master highway network
4. Create highway networks by time-of-day

Once a project-specific highway network is extracted from the master network, the transit background network is created. The transit background network is later used in creating the transit network.

1. Master Network

The master highway network consists of all the highway links for all projects. In the master network file, the analyst codes each link with attributes common to all projects, (such as distance) and also codes each link with the project-specific attributes such as area type, facility type, and number of lanes. Table 1 shows the list of project-specific variables in the master highway network. The attribute table lists the possible values for each of the project-specific variables.

Table 1 Project Specific Link Attribute Table

Attribute	Description	Example Attribute Name {Values}
LANE{Project}	Number of Lanes	laneRTP2040Base {0,1,2,3,---}
TOS{Project}	Special Speed Capacity	TOSRTP2040Base {0,1,2,3,---}
SIG{Project}	Signal Specific Lane	SIGRTP2040Base {0,1,2,3,---}
USE{Project}	User Class Type	USERTP2040Base {0,1,2,3,---}
TCLASS{Project}	Toll Class Type	TCLASSRTP2040Base {0,1,2,3,---}
HOT{Project}	High Occupancy Toll	HOTRTP2040Base {0,1,2,3,---}
FT{Project}	Facility Type	FTRTP2040Base {0,1,2,3,---}
AT{Project}	Area Type	ATRTP2040Base {0,1,2,3,---}
BRT{Project}	Exclusive BRT Lanes	BRTRTP2040Base {0,1,2,3,---}

At the beginning of a new project, the analyst must check the master network to determine if the appropriate links and link attributes exists in the master network for that specific project. If the links and/or link attributes do not exist or do not represent the project, then the analyst must code the appropriate links and their attributes into the master network. The analyst must keep the master network up to date by adding new highway links and variables that define the latest projects.

2. Create a New Project in the Master Network

The analyst first must check the master network for the project-specific links and variables. If the project is not defined then the analyst must add new links to the master network, usually by copying and pasting similar nearby links. After creating a new link, the analyst must set the project-specific attributes defined in Table 1. To do this, the analyst must run the script RTP2040_Base.job to create a new set of project-specific link variables in the master network that they then edit the attributes that are specific to the project.

2.1 Script RTP2040_Base.job

This script adds a new set of project-specific variables to the highway network by duplicating a set of project-specific variables and renaming them with the user specified (i.e. current) project name. Table 2 shows the list of new variables added to the master highway network file and Table 3 lists the input and output files of the script. The analyst is required to run this script only to update the master network file before exporting the project-specific network.

Table 2 Project Specific Variables Added by RTP2040_Base.job

Attribute	Description	Example Attribute Name {Values}
LANE{CurrentProject}	LANE{CurrentProject} = LANE{Old}	2
FT{CurrentProject}	FT{CurrentProject} = FT{Old}	3
TOS{CurrentProject}	TOS{CurrentProject} = TOS{Old}	0
HOT{CurrentProject}	HOT{CurrentProject} = HOT{Old}	1
SIG{CurrentProject}	SIG{CurrentProject} = SIG{Old}	0
USE{CurrentProject}	USE{CurrentProject} = USE{Old}	1
TCLASS{CurrentProject}	TCLASS{CurrentProject} = 0	0

Note that the TCLASS{CurrentProject} variable is coded as zero as it needs to be changed manually based on the project

Table 3 Input and Output Files of RTP2040_Base.job

Input/Output	Description	Example
I	Old Master Highway Network	MASTER_NETWORK_December22_2010.NET
O	New Master Highway Network	MASTER_NETWORK_March30_2011.NET

3. Extracting a Project Network from the Master Network

After creating project specific links and attributes in the master highway network, the analyst extracts a project specific network with the scripts Create 2040_Base.job and Network_Update_Modified.job.

3.1 Script "Create 2040_Base.job"

This script extracts the project-specific highway network from the master network. The script creates a project-specific highway network from the master highway network with only the required attributes shown in Table 4. All of the project-specific attributes are renamed to drop the project name suffix and links with the setting LANE=0 are excluded during the extracting process. Many of the attributes are empty at this point since their value has yet to be calculated. Table 5 lists the input and output files of the script.

Table 4 Project Specific Link Attributes

Variable	Description	Example
A	From node	20298
B	To node	20300
DISTANCE	Link Distance (miles)	14.1
SPDCLASS	Speed Class Type	19
CAPCLASS	Capacity Class Type	19
ROUTENUM	??	238
AUX	??	0
YEAR	Year	0
FFS	Free Flow Speed	60
FFT	Free Flow Time	14.1
FT2000	Facility Type in Year 2000	2
GL	County Code	4
LANES	Number of Lanes	2
TOLLCLASS	Toll Class Type	0
USE	User Class Type	1
OT	Observed Time for Toll Queuing Links	0
CAP	Capacity Per Lane	1950
AT	Area Type	3
FT	Facility Type	2
TOS	Special Speed Capacity	1
HOT	High Occupancy Toll	0
TSIN	Time-based link	1
SIGCOR	Signal coordinated link	1

Table 5 Input and Output Files of Create 2040_Base.job

Input/Output	Description	Example
I	Master Highway Network	MASTER_NETWORK_December22_2010.NET
O	Project Specific Highway Network	Year2040_Base_NETWORK_December22_2010_w.NET

3.2 Script "Network_Update_Modified.job"

This script updates the project-specific highway network file with calculated attributes and writes out a new highway network file. The primary calculated attributes are capacity and free flow speed, but other attributes are set as well as shown in Table 6. The analyst is required to run this script after running the Create 2040_Base.job script. Table 7 shows the input and output files of the script.

Table 6 Highway Network Calculated Link Attributes

Variable	Description	Example
METER	Ramp meter present, set If(FT2000=8)	1
FT	Facility type modified IF (FT=8) FT=5	2
FT2000	Facility type in year 2000 modified IF (FT2000=8) FT2000=5	2
CAPCLASS	Capacity class type, set by AT, FT, TOS and SIGCOR type lookup	19
FFS	Free flow speed, set by CAPCLASS	60
CAP	Capacity per lane, set by CAPCLASS	1950
FFT	Free flow time, calculated as (DISTANCE/FFS)*60 or as OT, IF(TSIN=1 & TOLLCLASS=1-100)	14.1
OT	Observed time, set to FFT If(TSIN=1 & TOLLCLASS=0)	3.5

Table 7 Input and Output Files of Network_Update_Modified.job

Input/Output	Description	Example
I	Project Specific Highway Network	Year2040_Base_NETWORK_December22_2010_w.NET
O	Output Updated Project Specific Highway Network	Year2040_Base_NETWORK_December22_2010.NET

4. Creating Highway Networks by Time of Day

After creating the project specific network file, the analyst must create the highway network files by time-of-day. This is done in two stages:

1. The analyst adds five sets of toll values to each link in the network where each set represents one of the five time periods shown in Table 8 and each set includes toll values for each user class.
2. The analyst runs the script to create five highway networks by time-of-day.

All tolls should be expressed in year 2000 cents. The scripts to do these two steps are: SetTolls.job followed by CreateFiveHighwayNetworks.job.

Table 8 Highway Network Time Periods

<timeperiod>Code	Name	Hours
EA	Early AM	3am to 6am
AM	AM Peak Period	6am to 10am
MD	Midday	10am to 3pm
PM	PM Peak Period	3pm to 7pm
EV	Evening	7pm to 3am

4.1 Script "SetTolls.job"

Before creating the time-of-day networks, but after creating the project-specific network, the analyst then updates the bridge and value tolls. Bridge tolls are the tolls charged at the bridges and value tolls are tolls paid to save time by shifting to an alternative facility (e.g. HOT) or nearby facility. Each of the eight existing Bay Area bridge toll booths links has a unique TOLL coded as shown in Table 9. All tolls should be expressed in year 2000 cents. To change a toll value, the script must be changed.

Table 9 Bay Area Bridge Toll Class

Toll Class Code	Bay Area Bridge	Example
1	Benicia-Martinez Bridge	If (A = 11597 & B = 11683) TOLL = 0
2	Carquinez Bridge	If (A = 11667 & B = 11634) TOLL = 0
3	Richmond Bridge	If (A = 2341 & B = 2357) TOLL = 0
4	Golden Gate Bridge	If (A = 7319 & B = 7338) TOLL = 0
5	San Francisco/ Oakland Bay Bridge	If (A = 2784 & B = 2802) TOLL = 0
6	San Mateo Bridge	If (A = 3642 & B = 3649) TOLL = 0
7	Dumbarton Bridge	If (A = 3895 & B = 3896) TOLL = 0
8	Antioch Bridge	If (A = 1673 & B = 1621) TOLL = 0
9*	Reserved for New Bridges
10*	Reserved for New Bridges
11*	Reserved for Value tolls which are used by HOT lanes and are defined in hwyParam.block

*Note that Toll Classes 9-11 are reserved for new bridges and test case scenarios.

The attribute TOLL is a legacy attribute and is no longer output by this script. Instead, TOLL is set first, then a new attribute TOLLCLASS is set to TOLL. The attribute TOLLCLASS then becomes the output. A separate toll can be specified for each vehicle class. The vehicle class link toll link attributes are shown in Table 10. A separate toll can be specified for each vehicle class, as shown in Table 11. Table 12 shows the inputs and outputs of this script.

Table 10 Toll User Class Specific Link Attributes

<userclass>Code	Description	Example
DA	Drive alone, SOV	200
S2	Shared ride two, HOV2	150
S3	Shared ride three plus, HOV3+	100
VSM	Very small commercial trucks, which are assumed to be two-axle vehicles	100
SML	Small commercial trucks, which are assumed to be two-axle vehicles	100
MED	Medium commercial trucks, which are assumed to be three-axle vehicles	100
LRG	Combination trucks, which are charged the average of the five- and six-axle fee	100

Table 11 Output Toll Class Link Attributes

Variable	Description	Example
TOLL<timeperiod>_<userclass>	Bridge and Value Tolls by User Class and Time of Day	TOLLEA_DA = 200
TOLLCLASS	Replaces TOLL values with TOLLCLASS	TOLLCLASS = TOLL

Table 12 Input and Output Files from this Script

Input/Output	Description	Example
I	Updated Project Specific highway Network	freeflow.net
O	Highway Network with Toll values	withTolls.net

4.2 Script "CreateFiveHighwayNetworks.job"

Once the toll values are coded, the analyst must run this script to create five highway network files by time-of-day. In addition to being used for highway assignment, the five time-of-day highway networks are used as the background networks in developing the transit access connectors, and are also used in the transit skimming and assignment procedures. All of the five networks are identical except for the following:

1. The reversible lanes on the Golden Gate bridge are coded in the southbound direction in the Early AM, AM Peak, and Midday periods and the northbound direction in the PM Peak and Evening periods.
2. The Caldecott tunnel is coded with <X> lanes in the westbound direction in the Early AM, AM Peak Period, and Midday periods and <X> lanes in the eastbound direction in the PM Peak and Evening periods.
3. The fixed time toll delay links are given time-of-day specific values.
4. The shared ride toll bypass lanes are either left in place or deleted.

The analyst runs the script CreateFiveHighwayNetworks.job to create these five networks. In this script, a new variable called PNROK is created with a zero value for certain bridges. This variable is then used in a later script to prevent park-and-ride paths from being built across these bridges. Table 13 and Table 14 show the script settings and input and output network files.

Table 13 Create Five Networks Script Input Link Attributes

Link Attribute Name	Description	Example
<BRIDGENAME>_BRIDGE_NOPNR	Disallows park-and-ride across certain bridges	benicia_bridge_nopnr
FFT	Sets the time-period-specific congested time equal to the free-flow time	CTIM = FFT
LANES	Sets the number of reversible lanes by time period on certain bridges	IF (a=7317 & b=7315 & time period=1) LANES = 2

Table 14 Input and Output Files of CreateFiveHighwayNetworks.job

Input/Output	Description	Example
I	Highway Network with Toll values	withTolls.net
O	Highway Network by Time of Day	avgload<timeperiod>.net