8/13/2019 2_Urban and Regional Transport Planning
1/19
12/11/20
Chapter Two
Urban and RegionalTransport Planning
Er. Satya Ram Duwal
1Transportation planning and engineering
Er.Satya Ram Duwal
COURSE OUTLINE
Transportation planning and engineering
Er.Satya Ram Duwal2
1.Differences between urban and regional planning
2.Differences in planning for movement of people
and goods
3.Hierarchical structure to transportation planning:
intermodal approach and integrated development
approach
4.Transport demand surveys and studies: survey
design and field studies, data requirements for
passenger and freight movements
5.Predicting future demand
Transportation planning and engineering
Er.Satya Ram Duwal3
Regional planning:
Regional planning is a category of planning and development
that deals with designing and placing infrastructure and other
elements across large area
Urban planning:
Urban, city and town planning is the integration of land use
planning and transport planning, to explore a very wide range
of aspects of the built and social environment of urbanized
municipalities and communities.
Transportation planning and engineering
Er.Satya Ram Duwal4
Differences between urban and regional planning
Difference between planning for
movement of goods and people
Vehicles
Transportinfrastructure
Persons andGoods
Transportation planning and engineering
Er.Satya Ram Duwal5
Transportation system hierarchy
Transportation planning and engineering
Er.Satya Ram Duwal6
8/13/2019 2_Urban and Regional Transport Planning
2/19
12/11/20
Transportation planning and engineering
Er.Satya Ram Duwal7
Transportation planning and engineering
Er.Satya Ram Duwal8
Transportation Survey
Basic movements in Transportation
survey:
Internal to internal
Internal to external
External to external
External to internal
Transportation planning and engineering
Er.Satya Ram Duwal9
Basic movement of transportation survey
Transportation planning and engineering
Er.Satya Ram Duwal10
Externaltoe
xternal
Internaltoi
nternal
External to Internal
External Cordon
Screen line
InternaltoE
xternal
Fig. Basic movements in a transportation syrvey
12/11/20 13 ER. SATYA RAM DUWAL 11
Survey data can be collected :
At home
During the trip
At the destination ends of trip.
Transportation planning and engineering
Er.Satya Ram Duwal12
8/13/2019 2_Urban and Regional Transport Planning
3/19
12/11/20
Following are some of the types of transportsurvey:
Home interview survey
Commercial vehicle survey
Taxi survey
Road side interview survey
Post card questionnaire survey
Registration number plate survey
Tags on vehicle survey
public transport survey
Traffic flow survey (roadside traffic count, intersectiontraffic count, vehicle speed survey)
Inventories of land-use and economic studies
Transportation planning and engineering
Er.Satya Ram Duwal13
1) Home interview survey Is the most reliable types of survey for the collection of
O-D data.
Is intended to yield data on the travel pattern of
residents of the household and general characteristicsof the household influencing trip making.
Information on travel pattern includes:
Number of trips made,
Origin and destination
Purpose of trip
Travel mode
Time of departure and arrival
Transportation planning and engineering
Er.Satya Ram Duwal14
Information on household characteristicsincludes:
Types of dwelling unit
Number of residents
Age, sex composition
Vehicle ownership
Number of driver
Family income
home interview may
Full interview technique
Home questionnaire
Transportation planning and engineering
Er.Satya Ram Duwal15
This is very expensive to conduct, thus generallymanuals on this survey have been developed.
12/11/2013 16ER.SATYA RAM DUWAL
2) Commercial vehicle survey
It is conducted to obtain information on
journey made by all commercial vehicles
based within the study area. Address of the
operators is obtained and forms are issued to
drivers with the request that they record
particulars of all trips they could make.
Transportation planning and engineering
Er.Satya Ram Duwal17 12/11/2013 ER. SATYA RAM DUWAL 18
8/13/2019 2_Urban and Regional Transport Planning
4/19
12/11/20
3) Taxi survey
Large urban areas usually have a
sizeable amount of travel is made bytaxi. In such cases separate taxi
survey is necessary to conduct. The
survey consists of issuing
questionnaire or log sheets to the
taxi drivers to complete them.
Transportation planning and engineering
Er.Satya Ram Duwal19
4) Road side interview survey
It is one of the methods of carryingout a screen line or cordon survey. Itcan be done by directly interviewingdrivers of the vehicles at selectedsurvey points or by issuing prepaidpost cards containing thequestionnaire to all or a sample ofthe drivers.
Transportation planning and engineering
Er.Satya Ram Duwal20
12/11/20 13 ER. SATYA RAM DUWAL 21
5) Post card questionnaire
In this method reply-paid
questionnaires are handed over to
each driver or a sample at the survey
points, and requesting them to
complete the information and result
by post. In developing country, this
method may not be suitable.
Transportation planning and engineering
Er.Satya Ram Duwal22
12/11/20 13 ER. SATYA RAM DUWAL 23
6) Registration Number Plate Survey
This method consists of noting theregistration numbers of vehicles entering
and leaving an area at survey points
located on the cordon line. By matching
the registration numbers of the vehicles
at points of the entry and exit from the
area, two points on the paths of the
vehicle can be identified.
Transportation planning and engineering
Er.Satya Ram Duwal24
8/13/2019 2_Urban and Regional Transport Planning
5/19
12/11/20
12/11/20 13 ER. SATYA RAM DUWAL 25
7) Tags on vehicle method
In this method at each point where the
roads cross the cordon lines vehicles are
stopped and a tag is fixed usually under
the windscreen wiper. The tags for
different survey stations have different
colour and shapes to identify the survey
station. The vehicles are stopped again at
the exit point when tags are collected
Transportation planning and engineering
Er.Satya Ram Duwal26
12/11/20 13 ER. SATYA RAM DUWAL 27
8) Public transport survey
In order to assess the number of bus
passenger passing through the external
cordon, the survey can either by direct
interview with passengers or by issuing post
card questionnaires.
Transportation planning and engineering
Er.Satya Ram Duwal28
12/11/20 13 ER. SATYA RAM DUWAL 29 12/11/20 13 ER. SATYA RAM DUWAL 30
8/13/2019 2_Urban and Regional Transport Planning
6/19
12/11/20
9) Traffic flow survey
Roadside traffic count
Intersection traffic count
Vehicle speed survey
Transportation planning and engineering
Er.Satya Ram Duwal31
11) Inventory of land-use and economic
activities:
Inventory of land use: Zones and classified as:
Residential
Industrial
Commercial
Recreational
Open space
Institution etc
Transportation planning and engineering
Er.Satya Ram Duwal32
Inventory of economic activities:
Population zone wise
Age sex, family composition
Employment statistics
Housing statistics
Income study
Vehicle ownership
Transportation planning and engineering
Er.Satya Ram Duwal33
Data of User characteristics - passenger
The most commonly used surveys in urban
transportation planning focus on data
collection in
household
Work place or special work generating place
Visitor or tourist centers
Vehicle intercept and external stations
Transit lines
12/11/20 13 ER. SATYA RAM DUWAL 34
12/11/2013 35ER. SATYA RAM DUWAL
Travel demand forecasting
Travel demand forecasting is the estimating
the demand for transport facilities and
services for future design period. Travel
demand forecasting is most important step in
transport planning.
Transportation planning and engineering
Er.Satya Ram Duwal36
8/13/2019 2_Urban and Regional Transport Planning
7/19
12/11/20
The traditional four step process
Trip generation forecasts the number of tripsthat will be made
Trip distribution determines where the trips go
Mode usage predicts how the trips will bedivided among the available modes of travel
Trip assignment predicts the routes that the tripswill take, resulting in traffic forecast for thehighway system and ridership forecast for thetransit system.
Transportation planning and engineering
Er.Satya Ram Duwal37
Transportation planning and engineering
Er.Satya Ram Duwal38
Four step transport planning
ER. SATYA RAM DUWAL 3912/11/2013
Chapter 3
urban transportation planning process
1. Planning phases: trip generation, trip
distribution, model split, and traffic
assignment
2. The supply side of transportation: the modes,
their roles and characteristics (capacity, costs
etc)
3. Other recent approaches to transportation
planning.
Transportation planning and engineering
Er.Satya Ram Duwal40
1. Trip generation
Trip generation is the process by which
measures of urban activity are converted in to
numbers of trips.
Trip ends are classified as being either a
productionor an attraction
Transportation planning and engineering
Er.Satya Ram Duwal41
Trip generationis the first step in the conventional four-
step transportation forecasting process (followed by trip
distribution, mode choice, and route assignment), widelyused for forecasting travel demands. It predicts the number
of trips originating in or destined for a particular traffic
analysis zone.
Typically, trip generation analysis focuses on residences,
and residential trip generation is thought of as a function
of the social and economic attributes of households. At the
level of the traffic analysis zone, residential land
uses"produce" or generate trips.
Trip Generation:
42ER. SATYA RAM DUWAL12/11/2013
http://en.wikipedia.org/wiki/Transportation_forecastinghttp://en.wikipedia.org/wiki/Trip_distributionhttp://en.wikipedia.org/wiki/Trip_distributionhttp://en.wikipedia.org/wiki/Mode_choicehttp://en.wikipedia.org/wiki/Route_assignmenthttp://en.wikipedia.org/wiki/Triphttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Househttp://en.wikipedia.org/wiki/Householdhttp://en.wikipedia.org/wiki/Land_usehttp://en.wikipedia.org/wiki/Land_usehttp://en.wikipedia.org/wiki/Land_usehttp://en.wikipedia.org/wiki/Land_usehttp://en.wikipedia.org/wiki/Land_usehttp://en.wikipedia.org/wiki/Householdhttp://en.wikipedia.org/wiki/Househttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Traffic_analysis_zonehttp://en.wikipedia.org/wiki/Triphttp://en.wikipedia.org/wiki/Route_assignmenthttp://en.wikipedia.org/wiki/Route_assignmenthttp://en.wikipedia.org/wiki/Route_assignmenthttp://en.wikipedia.org/wiki/Mode_choicehttp://en.wikipedia.org/wiki/Mode_choicehttp://en.wikipedia.org/wiki/Mode_choicehttp://en.wikipedia.org/wiki/Trip_distributionhttp://en.wikipedia.org/wiki/Trip_distributionhttp://en.wikipedia.org/wiki/Trip_distributionhttp://en.wikipedia.org/wiki/Transportation_forecastinghttp://en.wikipedia.org/wiki/Transportation_forecastinghttp://en.wikipedia.org/wiki/Transportation_forecasting8/13/2019 2_Urban and Regional Transport Planning
8/19
12/11/20
12/11/2013 43ER. SATYA RAM DUWAL 12/11/20 13 44ER. SATYA RAM DUWAL
12/11/2013 45ER. SATYA RAM DUWAL 12/11/20 13 46ER. SATYA RAM DUWAL
Transportation planning and engineering
Er.Satya Ram Duwal47
Factors that influence production
The following factors influence the production of a zone:
Households characteristics-Income
-Household structure (number going to work, number going toschool, age )
-Car ownership
Zone characteristics
-Land use
-Land price
-Residential density, rate of urbanisation
Accessibility
-Extent of transport options from the zone.
-Quality of transport options from the zone
Transportation planning and engineering
Er.Satya Ram Duwal48
8/13/2019 2_Urban and Regional Transport Planning
9/19
12/11/20
Factors that influence attraction Number of employees
Land-use
-Industrial (type of industry, occupied area)
-Educational facilities
-Shops (floor area, sales)-Service sector (hospitals, banks, governmentinstitutions, conference centres )
-Recreational (sport centres, tourist- or amenity sites,theatres )
-Storage and transfer (harbours, airports )
Accessibility
-Extent of transport options to the zone
-Quality of transport options to the zone
Transportation planning and engineering
Er.Satya Ram Duwal49
1.1 Trip generation models:
Transportation planning and engineering
Er.Satya Ram Duwal50
iii tFT
Basic equation for the Growth factor model ing
1.1.1. Growth facto r mo del ing
Where, Ti and tiare respectively future and current trips in zone i
and Fi is the growth factor. Normally growth factor is related to
variables such as population (P), income (I), car ownership (C), in a
function such that:
)(
)(
ci
ci
ci
di
di
di
iCIPf
CIPfF
Wheref can be a direct multiplicative function with no parameter,
and the superscripts dand cdenote the design and current years
respectively
Transportation planning and engineering
Er.Satya Ram Duwal51
Example: Consider a zone with 250 households with
a car and 250 households without car. Assuming we
know the average trip generation rate of each group:
Car owning household produce: 6 trips /day
Non-car owning household produce: 2.5 trips /day
daytripsXXti /0.21250.62505.2250
Transportation planning and engineering
Er.Satya Ram Duwal52
Let us assume that in the future all household
will have a car; therefore, assuming that
income and population remain constant, we
can estimate simple multiplicative growth
factor:
2ci
di
iC
CF
Transportation planning and engineering
Er.Satya Ram Duwal53
daytripsXTi /425021252
daytripsXTi /30006500
Applying the growth factor model;
However, this method is crud.
We can estimate future number of trips generated as:
Transportation planning and engineering
Er.Satya Ram Duwal54
8/13/2019 2_Urban and Regional Transport Planning
10/19
12/11/20
Transportation planning and engineering
Er.Satya Ram Duwal55
.........332211 XbXbXbaY
1.1.2. Regression analysis
In a linear regression model we try to predict a
variable Y as a linear function of one or more
influence variablesXi
Transportation planning and engineering
Er.Satya Ram Duwal56
Transportation planning and engineering
Er.Satya Ram Duwal57
Transportation planning and engineering
Er.Satya Ram Duwal58
Dependent Variable
(Y) = Trip generation per household
Independent Variable X1= cost per trip
X2= No of workers per household
X3= vehicle ownership
The Regression equation will be
Y = a X1+ b X2+ c X3+d
ER. SATYA RAM DUWAL 59
Regression Analysis
12/11/2013
Y X1
X2
X3
Trip generation
per household
Total Cost of
trip
No of workers
per household
Vehicle
ownership
6 48 4 0
4 34 2 1
3 24 2 0
5 191 3 2
6 48 4 0
6 198 4 4
3 24 2 0
3 48 2 1
2 16 1 1
4 66 2 2ER. SATYA RAM DUWAL 60
Trip Generation Survey (site Pepsikola)
12/11/2013
8/13/2019 2_Urban and Regional Transport Planning
11/19
12/11/20
Trip generation
per household
Total Cost of
trip
No of workers
per household
Vehicle
ownership
6 48 4 0
3 68 2 12 16 1 0
6 108 4 1
2 16 1 0
2 25 1 1
6 318 4 3
5 40 3 0
4 32 2 0
6 327 4 4
ER. SATYA RAM DUWAL 61
Trip Generation Survey (site Kupandol)
12/11/2013
Trip generation
per household
Total Cost of
trip
No of workers
per household
Vehicle
ownership
4 98 2 2
6 57 4 25 68 3 1
3 24 2 0
3 64 2 1
6 84 4 1
6 228 4 2
4 32 2 0
5 40 3 0
6 66 4 2
ER. SATYA RAM DUWAL 62
Trip Generation Survey (site Kritipur)
12/11/2013
Categories Total Numbers Categories Total Numbers
0 vehicle 12 No Vehicle 12
1 vehicle 9 With Vehicle 18
2 vehicle 6
3 vehicle 1
4 vehicle 2
ER. SATYA RAM DUWAL 6312/11/2013
Correlation between the independent variable must be
avoid for regression analysis.
Analysis Options for Three independent Variables
Dependent Variable(Y) vary only one variable for best fit.
Dependent variable(Y) vary only two variable for best fit.
Dependent variable(Y) vary three variable for best fit.
ER. SATYA RAM DUWAL 64
Analysis Options and relation between the variable
12/11/2013
Regression
Statistics
Trip generation per
household Vs.Cost per trip
(b=c=0)
No of workers per
household (a=c=0)
Vehicle ownership
(a=b=0)
Multiple R 0.549430149 0.976051408 0.415821653
R Square 0.301873489 0.952676352 0.172907647
Adjusted R Square 0.276940399 0.950986222 0.143368635
Standard Error 1.275004881 0.331958574 1.387783709
Observations 30 30 30
ER. SATYA RAM DUWAL 65
Analysis Using Single Variable
Y = a X1+ b X2+ c X3+d
12/11/2013
Regression
Statistics
Trip generation per
household Vs.
Cost per trip (a=0)No of workers per
household (b=0)
Vehicle ownership
(c=0)
Multiple R 0.549430149 0.976051408 0.415821653
R Square 0.301873489 0.952676352 0.172907647
Adjusted R Square 0.276940399 0.950986222 0.143368635
Standard Error 1.275004881 0.331958574 1.387783709
Observations 30 30 30
ER. SATYA RAM DUWAL 66
Analysis Using Two Variable
Y = a X1+ b X2+ c X3+d
12/11/2013
8/13/2019 2_Urban and Regional Transport Planning
12/19
12/11/20
Regression Statistics
Multiple R 0.976292927
R Square 0.953147879
Adjusted R Square 0.947741865
Standard Error 0.342769168
Observations 30
ER. SATYA RAM DUWAL 67
Analysis Using Three Variable
Result: Best fit Regression model is, Using Three
Variables
12/11/2013
CoefficientsStandard
Errort Stat P-value Lower 95% Upper 95%
Intercept 0.791660 0.173657 4.558746 0.00011 0.43470 1.14862
Cost per trip -0.000494 0.001463 -0.337578 0.73839 -0.00350 0.00251
No of workers
per household1.316094 0.069439 18.953341 9.65E-17 1.17336 1.45883
Vehicle
ownership0.048230 0.095827 0.503308 0.61899 -0.14874 0.24520
ER. SATYA RAM DUWAL 68
The Regresin Equation may beY= -0.000494 X1+1.316094 X2+ 0.048230 X3+ 0.791660
12/11/2013
ER. SATYA RAM DUWAL 69
0
1
2
3
4
5
6
7
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29
NumberofTripgereratedperhousehold
Household Indicator number
Actual Trip generation per household Predicted Trip generation per household
Analysis between Actual trips and Estimated trips
12/11/20 13 ER. SATYA RAM DUWAL 70
-1
0
1
2
3
4
5
6
7
1 4 7 10 13 16 19 22 25 28
NumberofTripgereratedperhousehold
Household Indicator number
Predicted Trip generation per household Residuals Actual Trip generation per household
Analysis between Actual trips and Estimated trips
12/11/2013
Regression Statistics
Multiple R 0.976292927
R Square 0.953147879
Adjusted R Square 0.951474589
Standard Error 0.322470174
Observations 30
ER. SATYA RAM DUWAL 71
Analysis between Actual trips and Estimated trips
Result: The relation between Actual and Estimated trip is
considerable so we can use this model for estimate trip
generation.12/11/20 13 ER. SATYA RAM DUWAL 72
-1
0
1
2
3
4
5
6
7
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29
NumberofTripgereratedperhousehold
Predicted Trip generation per household Residuals Actual Trip generation per household
Analysis between Actual trips and Estimated trips
12/11/2013
8/13/2019 2_Urban and Regional Transport Planning
13/19
12/11/20
1.1.3. Category analysis or cross classification
In a category analysis the population of the
study area is divided into a number of
homogenous groups or categories, based on
specific socio-economic characteristics.
The trip behavior is determined for each of
the categories, with the understanding that
this will remain stable over time.
Transportation planning and engineering
Er.Satya Ram Duwal73
Example:
A Number of household and total trips made, categorized by
household size and car ownership level.
Transportation planning and engineering
Er.Satya Ram Duwal74
a)Automobile ownership
0 1 2 or more
Family
size HH No
Total
trips HH No
Total
trips HH No
Total
trips
1 925 1098 1872 4821 121 206
2 1471 2105 1934 6129 692 1501
3 1268 1850 3071 13989 4178 19782
4 or
more 745 1509 4181 18411 4967 25106
Transportation planning and engineering
Er.Satya Ram Duwal75
b)Household trip rates
Automobile ownership
Family size 0 1 2 or more
1 1.19 2.58 1.70
2 1.43 3.17 2.17
3 1.46 4.56 4.734 or more 2.03 4.40 5.05
1098/925
c)Forecasted number of households in one zone,
categorized by household size and car
ownership level
Transportation planning and engineering
Er.Satya Ram Duwal76
Automobile ownership
Family
size 0 1 2 or more
1 24 42 8
2 10 51 107
3 11 31 158
4 or more 3 17 309
d) Forecasted number of trips for this
zone
Transportation planning and engineering
Er.Satya Ram Duwal77
Automobile ownership
Familysize 0 1 2 or more Total
1 28 108 14 150
2 14 162 232 408
3 16 141 748 905
4 or more 6 75 1562 1643
Total 65 486 2556 3106
24 X 1.19
1.2 Trip Distribution models
The aim of a distribution model can now be
described as follows:
Distribute the trips that originate in a particular zone over
all destinations
Distribute the trips with a destination in a particular zone
over all origins
Therefore main aim is to determine the O-D
table for a particular forecast year
Transportation planning and engineering
Er.Satya Ram Duwal78
8/13/2019 2_Urban and Regional Transport Planning
14/19
12/11/20
1.2.1 Gravity model:
Transportation planning and engineering
Er.Satya Ram Duwal79
Ti-jNumber of trips from itoj
K and n-constant
Piis production of i
Ai is the attraction ofi
D is the distance betweenI and j
Transportation planning and engineering
Er.Satya Ram Duwal80
zones Trips
produced
Trips attracted
A 1500 2500
B 2500 3000
C 3000 1500
Example: Total trips produced in and attracted to the 3 zones A,B,C of a survey
area in the design year is tabulated as:
It is known that the trips between two zones are inversely proportion to the
second power of the travel time between zones, which is uniformly 25
minutes. If the trip interchange between zones B and C is known to be 350,
calculate the interchange between zones A and B, A and C , B and A and C
and B
Solution hint
Determine value of K using given data Ti-j=350, d=25,
Pi=PB=2500 , Pj = Pc=1500, n=2 given on question
For trip interchange between A and C, d=25,
Pi=PA=1500 , Pj = Pc=1500, n=2 and so on
Use i as trip produced and j as trip attracted.
Transportation planning and engineering
Er.Satya Ram Duwal81
1.2.2 GROWTH FACTOR METHOD
1.2.2.1 Uniform Growth (constant) factor method
Transportation planning and engineering
Er.Satya Ram Duwal82
Transportation planning and engineering
Er.Satya Ram Duwal83
1.2.2.1.1 Singly constrained growth factor methods
Used where information is available on the expected growth in
trips originating from zones.
Consider the following trip matrix
Transportation planning and engineering
Er.Satya Ram Duwal84
Method
Multiply each cell in Row 1 by 400/355
Multiply each cell in Row 2 by 460/455
Multiply each cell in Row 3 by 400/255
Multiply each cell in Row 4 by 702/570
8/13/2019 2_Urban and Regional Transport Planning
15/19
12/11/20
Transportation planning and engineering
Er.Satya Ram Duwal85
1.2.2.1.2 The Furness Method (Doubly constrained
growth factor method)
Transportation planning and engineering
Er.Satya Ram Duwal86
Transportation planning and engineering
Er.Satya Ram Duwal87
Transportation planning and engineering
Er.Satya Ram Duwal88
Comments on Growth Factor Methods
1. Tends to overestimate the trips between
densely populated zones which probably have
little further development potential
2. Tends to underestimate the future trips
between underdeveloped zones which could
be extensively populated in the future
Transportation planning and engineering
Er.Satya Ram Duwal89
Travel impedance and the deterrence
function
Travel impedance
The effort involved, or the resistance againstundertaking a trip is called travel impedance.
It would seem obvious to express this impedance
simply in terms of the travel time or distance
involved
Transportation planning and engineering
Er.Satya Ram Duwal90
8/13/2019 2_Urban and Regional Transport Planning
16/19
12/11/20
Transportation planning and engineering
Er.Satya Ram Duwal91
The total impedance of a trip fromi tojvia route rfor a specific
transport mode can be written as a linear combination of the
experienced subjective time duration and monetary costs .
The minimum of this expression calculated over all possible routes is
the travel impedance cij between i and j.
Here the value of time is expressed in money-units per time unit
(euro/hour, forexample).
The value of time indicates that the traveller is prepared to pay
money-units for a saved time-unit of travel time. In the formula, the
monetary costs Kijr have been converted to time units via the .
In public transport the duration times ts and costs ks of the
various components which together make up the journey
from i to j via route r are multiplied by the weighting factors
sands
Transportation planning and engineering
Er.Satya Ram Duwal92
Deterrence function It is intuitively clear that the number of trips to a destination
decreases as the distance (or rather the travel impedance) to that
destination increases.
This travel impedance effect on the distribution of trips is expressed
by the deterrence function F(cij) .
Separate deterrence functions are applied depending on the
purpose of the trip, on personal characteristics and on the mode of
transport.
Some functions that have been used are:
Transportation planning and engineering
Er.Satya Ram Duwal93
Parametersa and b in the functions above are determined through
calibration using observations from the study area.
The general shape of the functions for some values of the
parameters is given as:
Transportation planning and engineering
Er.Satya Ram Duwal94
1.3 Modal split models
(Mode choice model)
Going somewhere not only involves a choice
of route but also a choice of transport mode.
The distribution of trips over the various
transport modes is called the modal split.
Modeling transport mode choice is one of the
classical problems in traffic engineering.
Transportation planning and engineering
Er.Satya Ram Duwal95
Transportation planning and engineering
Er.Satya Ram Duwal96
8/13/2019 2_Urban and Regional Transport Planning
17/19
12/11/20
Transportation planning and engineering
Er.Satya Ram Duwal97
Factors that influence transport mode choiceSocioeconomic Characteristics of Trip Maker
- Car Availability and/or ownership
- Possession of driving license
- Household Structure
- Income
- Residential Density
Characteristics of Journey
- Trip purpose
- Time of day of travel
Characteristics of Transport System
- Travel time
- Waiting Time
- Travel cost
- Comfort & Convenience
- Reliability & regularity
- Protection & Security
Transportation planning and engineering
Er.Satya Ram Duwal98
People who have no choice but to use one orother transport mode are called captivesof thattransport mode.
Those people who are not captive to one or otherform of transport are called choice-travelers.
When a household has no access to a car whilethe destination is too far away to cycle or walk,and when family income does not stretch to carhire or taxi, the family member is said to be apublic transport captive.
Transportation planning and engineering
Er.Satya Ram Duwal99
LOGITMODEL
Transportation planning and engineering
Er.Satya Ram Duwal100
. The formula shows that the probability that
alternative a is chosen, depends on the observed
utilities of the alternatives, and also on the dispersion
parameter.
If we let = 1, the logit model becomes
Transportation planning and engineering
Er.Satya Ram Duwal101
Pr(a) = the probability that a will be chosen.
Vk = the observable utility of travel mode k
K = the number of alternative travel modes
EAMPLE:1
Transportation planning and engineering
Er.Satya Ram Duwal102
Imagine a situation in which one can choose between three transport modes:
car, bus and bicycle. Assume that the observable utilities Vkfor a particular
group of people (who have the same personal characteristics) can be given by
the following functions:
Where; T and K are, respectively, travel time and travel costs, and they have
the following values:
What is the probability that a particular travel mode will be chosen by
individuals
8/13/2019 2_Urban and Regional Transport Planning
18/19
12/11/20
Transportation planning and engineering
Er.Satya Ram Duwal103
EXAMPLE :2The calibrated utility function for private car and
public transport travel are:
where, X= in-vehicle travel time; Y=out of
vehicle travel time; C=cost of travel/income
What is the probability that a person with income Rs.10000 will
travel by public transport?
Transportation planning and engineering
Er.Satya Ram Duwal104
private car: Vc= -0.3-0.04X-0.1Y-.03C
public transport: Cp= - 0.04X-0.1Y-0.03C
private car public transport
in-vehicle travel time 15 40
out-of vehicle travel time 5 10
travel cost(Rs.) 300 75
1.4 Traffic assignment
The primary concern in traffic assignment
models is route choice. It would appear self-
evident that a traveler would, in principle,
choose the shortest route to his point of
destination. This is why shortest route
algorithms play an important role in traffic
assignment models.
Transportation planning and engineering
Er.Satya Ram Duwal105
The application of traffic assignment
To determine the deficiencies in the existing
transportation system by assigning the future
trips to the existing system;
To evaluate the effects of the limited
improvements;
To develop the construction priorities by
assigning estimated future trips for intermediate
years to the transportation system; To test the transportation system proposals;
Transportation planning and engineering
Er.Satya Ram Duwal106
Types of assignment model
Travelers will choose the route which will take minimum travel time,
minimum travel distance dependent on the traffic volume on theroad.
The following are commonly used traffic assignment models.
1) All-or-nothing assignment model
2) Multiple route assignment model
3) Capacity restraint assignment model
4) Capacity restraint multipath route assignment model
5) Diversion curves technique model
Transportation planning and engineering
Er.Satya Ram Duwal107
1.4.1 All-Or-Nothing Assignment Model:
simplest model and is based on the premise that the
route followed by traffic is one having the least travel
resistance.
This model is also called shortest path model.
The resistance itself can be measured in terms of
travel time, distance, cost or a suitable combination
of these parameters.
This model assumes that either all drivers prefer a
particular route or nobody will take that route.
Transportation planning and engineering
Er.Satya Ram Duwal108
8/13/2019 2_Urban and Regional Transport Planning
19/19
12/11/20
1.4.2 Multiple Route Assignment Model:
All road users may not be able to judge the minimumpath for themselves.
It may also happen that all road users may not have thesame criteria for judging the shortest route.
These limitations of the all-or-nothing approach arerecognized in the multiple route assignment models.
The method consists of assigning the inter zonal flowto a series of routes, the proportion of total flowassigned to each being a function of the length of thatroute in relation to the shortest route.
Transportation planning and engineering
Er.Satya Ram Duwal109
1.4.3 Capacity Restraint Assignment Model:
This is the process in which the travel resistance of a link is
increased according to a relation between the practical capacity of
the link and the volume assigned to the link.
This model assumed that if the traffic volume on a road is increased
beyond the capacity its resistance to flow is also increased.
This model is also known as the Wyne state arterial assignment.
Transportation planning and engineering
Er.Satya Ram Duwal110
1.4.4 Capacity Restraint Multipath Route Assignment
Model:
This model is almost same as multipath route
assignment model but in this model we also
consider the capacity of each link instead of
only distance.
This model can be considered as combination
of capacity restraint and multipath model.
Transportation planning and engineering
Er.Satya Ram Duwal111
1.4.5 Diversion Curves Model:
Diversion curves represent empirically derived
relationship showing the proportion of traffic that is
likely to be diverted on a new facility (bypass, new
expressway, new arterial street, etc.) once such a
facility is constructed.
It is a one of the frequently used assignment model.
This model is based on the travel time saved,
distance saved, travel time ratio, travel distance ratio,
distance and speed ratio, travel cost ratio, etc.
Transportation planning and engineering
Er.Satya Ram Duwal112
Bureau of Public Roads curve fitted to this formula:
P = 100/(1+tr 6)
Where, P=% of the traffic diverted to new system
tr=travel time ratio(time on new system /time on old system)
California Curves Model:
In the California curves model, travel time saved and distance saved for
two routes can be assigned the traffic.
Transportation planning and engineering
Er.Satya Ram Duwal113
Example:
In order to relieve congestion on an urban street network
a motorway is proposed to be constructed. The travel timefrom one zone centroid to another via the proposed
motorway is estimated to be 10 mins whereas the time for
the same travel via existing street is 18 mins. The flow
between the two zone centroids is 1000 vehicles per hour.
Assign the flow between the new motorway and existing
streets.
Transportation planning and engineering
Er.Satya Ram Duwal114
Top Related