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TravelModelOneV05

Lisa Zorn edited this page Nov 7, 2017 · 1 revision

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Table of Contents

What is Travel Model One (v 0.5)?

Travel Model One v0.5 is an update to MTC's Activity-Based Travel Model that incorporates the effects of pavement quality on auto, transit and truck travel. This is done in several ways:

  • For auto and truck travel, the monetary cost of a link has been updated based on link attributes rather than assuming a uniform operating cost (per mile) throughout the network.
  • For transit travel, additional boarding and in-vehicle delays are assessed based on the distance traveled for specific transit modes.
The following changes were made to Travel Model One in order to incorporate the effects of pavement quality on auto operating costs.

Inputs

Roadway Network

For Travel Model One v0.5, the input roadway network (INPUT\hwy\freeflow.NET) is required to have an attribute, cityid, for each link, which is an integer code for the city in which the link is situated. Additionally, the county code (gl) is used if the pavement conditions for that city is unknown.

See AttachShapeToNetwork.

Auto Operating Costs

In Travel Model One v0.4, a single auto operating cost was specified in INPUT\params.properties:

# Units = year 2000 cents per mile
AutoOperatingCost = 16.80

For Travel Model One v0.5, this auto operating cost has been split into two separate components: 1 Repair and maintence cost 1 Fuel cost

Further, the auto operating costs specified in INPUT\params.properties now represents the auto operating costs for streets and roads in a "perfect" state of repair. These "perfect" costs will then be factored up based upon the average Pavement Condition Index (PCI) of the city in which the link is situated. These city-based adjustments apply to non-freeway links only (facility types 3,4,6,7), because they are maintained by the city. For the remaining freeway links, the same file also specifies the freeway adjustment factors to be used.

# Units = year 2000 cents per mile
AutoOpCost_perfect_RM      =  4.29
AutoOpCost_perfect_Fuel    = 12.04
# freeway adjustments based on average PCI
AutoOpCost_fwyadj_RM       = 1.00000
AutoOpCost_fwyadj_Fuel     = 1.03984

City-based auto operating cost adjustments are specified in a new input file, INPUT\sgr\city_opcost_adjustment.csv. This file contains the following columns:

Column Description
1 cityid in the roadway network, an integer
2 city name, a string
3 year, an integer. This isn't used but it helps to clarify the relevant year for this data.
4 auto repair & maintenance cost adjustment
5 auto fuel cost adjustment
6 small truck repair & maintenance cost adjustment
7 small truck fuel cost adjustment
8 large truck repair & maintenance cost adjustment
9 large truck fuel cost adjustment
10 bus repair & maintenance cost adjustment
11 bus fuel cost adjustment

Note that several of these rows refer to county remainders (one for each of the 9 counties), so if a link's cityid is not found here, the relevant county remainder cost adjustments will be used.

Truck Operating Costs

Similarly, the previous truck operating cost in INPUT\params.properties changed from

TruckOperatingCost   = 42.94

For Travel Model One v0.5, the configuration requires more detail, including operating costs for small and large trucks, for both perfect local roads as well as for freeways.

# Units = year 2000 cents per mile
SmTruckOpCost_perfect_RM   =  8.57
SmTruckOpCost_perfect_Fuel = 24.60
# freeway adjustments based on average PCI
SmTruckOpCost_fwyadj_RM    = 1.00000
SmTruckOpCost_fwyadj_Fuel  = 1.01772

# Units = year 2000 cents per mile
LrTruckOpCost_perfect_RM   = 12.86
LrTruckOpCost_perfect_Fuel = 36.33
# freeway adjustments based on average PCI
LrTruckOpCost_fwyadj_RM    = 1.00000
LrTruckOpCost_fwyadj_Fuel  = 1.03365

The city-based adjustments for trucks are included in INPUT\sgr\city_opcost_adjustment.csv, as described above.

Bus Operating Costs

The INPUT\params.properties should also include operating costs for buses, for both perfect local roads as well as for freeways.

# Units = year 2000 cents per mile
BusOpCost_perfect_RM       = 12.86
BusOpCost_perfect_Fuel     = 36.33
# freeway adjustments based on average PCI
BusOpCost_fwyadj_RM        = 1.00000
BusOpCost_fwyadj_Fuel      = 1.03365

The city-based adjustments for buses are included in INPUT\sgr\city_opcost_adjustment.csv, as described above.

Transit Delays

Transit delays are configured in two files and they are coded by transit mode.

In INPUT\sgr\Boarding_Penalties_by_Mode_Code.block, additional boarding penalties are configured for different transit modes. The units are minutes x 100.

_board_30  = 26.7010
_board_133 = 32.0269
_board_120 = 53.1122
...

In INPUT\sgr\Invehicle_Penalties_by_Mode_Code.block, in vehicle penalties are configured for different transit modes. The units here are (minutes x 100)/mile.

_invehicle_30  = 0.7382
_invehicle_133 = 0.1900
_invehicle_120 = 2.9124
...

Process

The primary changes to the Travel Model One process in order to reflect pavement condition costs are as follows:

  1. In the preprocessing step, the new script scripts/preprocess/AddPavementCost.job performs the lookup of the various city-indexed cost adjustment factors, and adds them to the network.
  2. In highway skimming, scripts/skims/HwySkims.job has been updated to use the link-based operating costs for autos and for trucks. In addition, the BTOLL skim tables also include the pavement costs, since these are read by the core choice models. An additional table is added to the roadway skim files for each vehicle class to encapsulate the additional pavement costs alone (that is, costs above the "perfect pavement" costs). This is because benefit/cost analysis comparing different modes needs this to be separate from the bridge toll costs, because bridge toll expenditure/revenue between scenario should not be included in a benefit/cost analysis.
  3. In transit skimming, scripts/skims/TransitSkims.job has been updated to assess the tally the distance traveled by each of the relevant transit modes. For transit modes with a positive distance, the boarding delay is added to the wait tables in the transit skims, and the in vehicle delay is added to the in-vehicle time tables.
  4. In highway assignment, scripts/assign/HwyAssign.job has been updated to use the link-based operating costs for autos and for trucks.
Additionally, a set of metrics have been developed in order to calculate costs and benefits of a particular scenario. These have been updated to include the effects of pavement costs. The configured bus costs are incorporated here.

Validation

Travel Model One v0.5 was validated for model years 2000, 2005 and 2010.

-- Main.LisaZorn - 27 Jan 2015

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