TRANSPORTATION PLANNING AND ENGINEERING (3-0)

HANDOUTS # 01

1. The Transportation System

1.1 Definition and Scope

A transportation system may be defined as “consisting of the fixed facilities, the flow entities and the
control system that permit people and goods to overcome the friction of geographical space efficiently
in order to participate in a timely manner in some desired activity”.

Or

“Transportation is the movement of people and goods from point A to point B or from one place to
another”.

1.2 Functional Components of Transportation System

1.2.1 Fixed Facilities

Fixed facilities are the physical components of the system that are fixed in space and constitute the
network of links (e.g., roadway segments, railway tracks, and pipes) and nodes (e.g., intersections,
interchanges, transit terminals, harbors, and airports) of the transportation system. Their design,
traditionally within the realm of civil engineering, includes soil and foundation engineering, structural
design, the design of drainage system, and geometric design, which is concerned with the physical
proportioning of the elements of fixed facilities.

Figure 1 Road Segment

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Figure 2 Railway track

Figure 3 Various intersections of road

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1.2.2 Flow Entities

Flow entities are the units that traverse the fixed facilities, they include vehicles, container units,
railway units and so on. In the case of highway system the fixed facilities are expected to accommodate
a wide variety of vehicle types, ranging from bicycles to large tractor-trailer combinations.

Figure 4 Flow entities of a transportation system

1.2.3 Control System

The control system consists of vehicular control and flow control. Vehicular control refers to the
technological way in which individual vehicles are guided on the fixed facilities, such control may be
manual or automated.

The flow control system consists of the means that permit the efficient and smooth operation of streams
of vehicles and the reduction of conflicts between vehicles. This system includes various types of
signing, marking, and signal systems and underlying rules of operation.

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 Figure 5 Road signs for control system

Figure 6 Road signal for control system

1.3 The Field of Transportation Engineering

The demand for people to move and their need for goods creates the demand for transportation.
People’s preferences in terms of time, money, comfort, and convenience prescribe the mode of
transportation used, provided of course that such a mode is available to the user.

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The Institute of Transportation Engineers (1987) defines Transportation engineering as “application
of technological and scientific principles to the planning, functional design, operation, and
management of facilities for any mode of transportation in order to provide for the safe, rapid,
comfortable, convenient, economical, and environmentally compatible movement of people and
goods.” Traffic engineering, a branch of transportation engineering is described as “that phase of
transportation engineering which deals with planning, design and traffic operation of roads, streets,
and highways, their network, terminals and relationships with other modes of transportation.”

1.3.1 Role of Transportation Engineer

Despite the diversity of problem types, institutional contexts and technical perspectives there is an
underlying unity: a body of theory and a set of basic principles to be utilized in every analysis of
transportation systems. The core of this is the transportation system analysis approach. The focus of
this is the interaction between the transportation and activity systems of the region. This approach is
to intervene, carefully and deliberately in the complex fabric of society to use transport effectively in
coordination with other public and private actions to achieve the goals of that society. For this the
analyst must have a substantial understanding of the systems and their interaction with activity
systems; which requires an understanding of the basic theoretical concepts and available empirical
knowledge. Or

A transport Engineer could:

• Review plans of a proposed downtown development to determine the effect on the traffic
system.
• Develop a system of crosswalks so that pedestrians can move safely through a busy
intersection.
• Redesign the runways of an airport in order to accommodate the new mega jumbo jets.
• Perform simulations of traffic flow at an intersection to make sure that the traffic can move
smoothly.

1.4 Major Disciplines of Transportation

Transportation engineering broadly consists of four major parts:

• Transportation Planning
• Geometric Design
• Pavement Design
• Traffic Engineering

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1.4.1 Transportation Planning

Transportation planning deals with the development of a comprehensive set of action plan for the
design, construction and operation of transportation facilities. Transportation planning essentially
involves the development of a transport model which will accurately represent both the current as well
as future transportation system.

1.4.2 Geometric Design

Geometric design deals with physical proportioning of other transportation facilities, in contrast with
the structural design of the facilities. The topics include the cross-sectional features, horizontal
alignment, vertical alignment and intersections. Although there are several modes of travel like road,
rail, air, etc., the underlying principles are common to a great extent.

1.4.3 Pavement Analysis and Design

Pavement design deals with the structural design of roads, both (bituminous and concrete), commonly
known as (flexible pavements and rigid pavements) respectively. It deals with the design of paving
materials, determination of the layer thickness, and construction and maintenance procedures. The
design mainly covers structural aspects, functional aspects, and drainage. The structural design ensures
the pavement has enough strength to withstand the impact of loads, functional design emphasizes the
riding quality, and the drainage design protects the pavement from damage due to water infiltration.

1.4.4 Traffic Engineering

Traffic engineering covers a broad range of engineering applications with a focus on the safety of the
public, the efficient use of transportation resources, and the mobility of people and goods. Traffic
engineering involves a variety of engineering and management skills, including design, operation, and
system optimization. In order to address the above requirement, the traffic engineer must first
understand the traffic flow behavior and characteristics through an extensive collection of traffic flow
data and analysis. Based on this analysis, traffic flow is controlled so that the transport infrastructure
is used optimally as well as with good service quality. In short, the role of a traffic engineer is to protect
the environment while providing mobility, to preserve scarce resources while assuring economic
activity, and to assure safety and security to people and vehicles, through both acceptable practices
and high-tech communications.

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1.5 Other Important Disciplines

In addition to the four major disciplines of transportation, several other important disciplines are being
evolved in the past few decades. Although it is difficult to categorize them into separate well defined
disciplines because of the significant overlap, it may be worth the effort to highlight the importance
given by the transportation community. They can be enumerated as below:

1.5.1 Public Transportation

Public transportation or mass transportation deals with study of the transportation system that meets
the travel needs of several people by sharing a vehicle. Generally, this focuses on the urban travel by
bus and rail transit. The major topics include characteristics of various modes; planning, management
and operations; and policies for promoting public transportation.

1.5.2 Financial and Economic Analysis

Transportation facilities require large capital investments. Therefore it is imperative that whoever
invests money should get the returns. When the government invests in transportation, its objective is
not often monetary returns; but social benefits. The economic analysis of transportation projects tries
to quantify the economic benefits which include saving in travel time, fuel consumption, etc. This will
help the planner in evaluating various projects and optimally allocate funds. On the contrary, private
sector investments require monetary profits from the projects. Financial evaluation tries to quantify
the return from a project.

1.5.3 Accident Analysis and Reduction

One of the silent killers of humanity is transportation. Several statistics evaluate that more people are
killed due to transportation than great wars and natural disasters. This discipline of transportation looks
at the causes of accidents, from the perspective of humans, roads, and vehicle and formulates plans for
the reduction.

1.5.4 Intelligent Transport System (ITS)

With advent to computers, communication, and vehicle technology, it is possible these days to operate
transportation system much effectively with significant reduction in the adverse impacts of
transportation. Intelligent transportation system offers better mobility, efficiency, and safety with the
help of the state-of-the-art-technology.

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In addition disciplines specific to various modes are also common. This includes railway engineering,
port and harbor engineering, and airport engineering.

1.6 Role of Transportation

The transportation contributes to the economic, industrial and cultural development of a country. The
importance of transportation of a country is comparable to the veins in the human body, just as a vein
in the human body maintains health by circulation of blood to different parts of the body, similarly
means of transportation keep the health of a Nation in good condition by keeping the goods and people
moving from one place to another. Every commodity needs transport facilities both at production stage
as well as distribution stage. In the production stage transport is needed for carrying raw material such
as seeds fertilizers etc., and in the distribution stage transportation is required to transport finished
products from farm and factories to the distribution Centre’s. Thus for economic cultural and social
development of a country an effective and adequate system of transportation is essential.

1.6.1 Economic Development and Transport

It is well known that every produce is utilized to satisfy the human needs and the products are not
entirely consumed locally. Thus they need to be transported to the areas of their demand. For their
transport a good and adequate system of transportation is essential. The cost of the commodity is
influenced to a great extent by the cost of its transportation. If near a big city a adequate system on
transportation connects the villages around it, the produce of villages can be brought to the city when
the need of the city for that produce can be fulfilled and villager may get a remunerative price for its
produce as vegetable, milk, food articles etc. in this way economy of villagers may improve. Thus for
the economic development of a region, an effective and adequate system of transportation is essential.

1.6.2 Social Effects of Transportation

Increase in mutual understanding: the improved transportation system encourages people to undertake
journey of nearby places as well as different parts of their own country and also to foreign countries.
In other words improved system of transportation enhances tourism. When people go out and meet
people of different regions, they get a chance to understand each other style of living and their problems
etc., also increase the income of local people.

Secondly due to the cheap and time saving transportation system people from nearby areas can go for
work in cities and can improve their living conditions. In can also reduce the slum in cities.

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The improved and adequate transportation system is essential for the general well-being of the
community. The rapid and efficient transport system is essential for sub-urban and intercity long
distance travel for business needs, social visit and tourist’s activities. This also encourages people to
live away from their place of work and this helps in reducing the population density of the city.

1.6.3 Aspect of Safety, Law and Order.

During riots, tensions etc., army of military forces can be rushed to the place of disturbances. To
maintain law and order at home it is essential to have an efficient system of transport net-work.

In case of external aggression to defend the territory of the country and to guard the boarders with
foreign countries transport facilities are essential to reach the farthest distance from the headquarters
and to rush the supplies of ration, medicine’s, arms and ammunition’s etc., to the place of need.

1.6.4 Environmental Role of Transportation

The negative effects of transportation is more dominating than its useful aspects as far as transportation
is concerned. There are numerous categories into which the environmental effects have been
categorized. They are explained in the following sections.

1.6.4.1 Safety

Growth of transportation has a very unfortunate impact on the society in terms of accidents. Worldwide
death and injuries from road accidents have reached epidemic proportions. Nearly 1.3 million people
die and about 15 million injured on the road accidents annually. Increased variation in the speeds and
vehicle density resulted in a high exposure to accidents. Accidents result in loss of life and permanent
disability, injury, and damage to property. Accidents also causes numerous non-quantifiable impacts
like loss of time, grief to the near ones of the victim, and inconvenience to the public. The loss of life
and damage from natural disasters, industrial accidents, or epidemic often receive significant attention
from both government and public. This is because their occurrence is concentrated but sparse. On the
other hand, accidents from transport sector are widespread and occurs with high frequency.

For instance, a study has predicted that death and disabilities resulting from road accidents in
comparison with other diseases will rise from ninth to third rank between 1990 and 2020. Road
accidents as cause to death and disability could rank below heart disease and clinical depression, and
ahead of stroke and all infectious diseases. Significant reduction to accident rate is achieved in the
developing countries by improved road designed maintenance, improved vehicle design, driver
education, and law enforcements. However in the developing nations, the rapid growth of personalized

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vehicles and poor infrastructure, road design, and law enforcement has resulted in growing accident
rate.

1.6.4.2 Air Pollution

All transport modes consume energy and the most common source of energy is from the burning of
fossil fuels like coal, petrol, diesel, etc. The relation between air pollution and respiratory disease have
been demonstrated by various studies and the detrimental effects on the planet earth is widely
recognized recently. The combustion of the fuels releases several contaminants into the atmosphere,
including carbon monoxide, hydrocarbons, oxides of nitrogen, and other particulate matter.
Hydrocarbons are the result of incomplete combustion of fuels. Particulate matters are minute solid or
liquid particles that are suspended in the atmosphere. They include aerosols, smoke, and dust particles.
These air pollutants once emitted into the atmosphere, undergo mixing and disperse into the
surroundings.

1.6.4.3 Noise Pollution

Sound is acoustical energy released into atmosphere by vibrating or moving bodies whereas noise is
unwanted sound produced. Transportation is a major contributor of noise pollution, especially in urban
areas. Noise is generated during both construction and operation. During construction, operation of
large equipment’s causes considerable noise to the neighborhood. During the operation, noise is
generated by the engine and exhaust systems of vehicle, aerodynamic friction, and the interaction
between the vehicle and the support system (road tire, rail-wheel). Extended exposure to excessive
sound has been shown to produce physical and psychological damage. Further, because of its
annoyance and disturbance, noise adds to mental stress and fatigue.

1.6.4.4 Energy Consumption

The spectacular growth in industrial and economic growth during the past century have been closely
related to an abundant supply of inexpensive energy from fossil fuels. Transportation sector is
unbelieved to consume more than half of the petroleum products. The compact of the shortage of fuel
was experienced during major wars when strict rationing was imposed in many countries. The impact
of this had cascading effects on many factors of society, especially in the price escalation of essential
commodities. However, this has few positive impacts; a shift to public transport system, a search for
energy efficient engines, and alternate fuels. During the time of fuel shortage, people shifted to cheaper
public transport system. Policy makers and planners, thereafter gave much emphasis to the public
transit which consume less energy per person. The second impact was in the development of fuel-

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efficient engines and devices and operational and maintenance practices. A fast depleting fossil fuel
has accelerated the search for energy efficient and environment friendly alternate energy source. The
research is active in the development of bio-fuels, hydrogen fuels and solar energy.

1.6.4.5 Other Impacts

Transportation directly or indirectly affects many other areas of society and few of them are listed
below:

• Almost all cities uses 20-30 percent of its land in transport facilities. Increased travel
requirement also require additional land for transport facilities. A good transportation system
takes considerable amount of land from the society.
• Aesthetics of a region is also affected by transportation. Road networks in quite country side
is visual intrusion. Similarly, the transportation facilities like fly-overs are again visual
intrusion in urban context.
• The social life and social pattern of a community is severely affected after the introduction of
some transportation facilities. Construction of new transportation facilities often require
substantial relocation of residents and employment opportunities.

1.7. History of Highway Engineering

Road transport is one of the most common mode of transport. Roads in the form of trackways, human
pathways etc., were used even from the pre-historic times. Since then many experiments were going
on to make the riding safe and comfort. Thus road construction became an inseparable part of many
civilizations and empires

The history of highway engineering gives us an idea about the roads of ancient times. Roads in Rome
were constructed in a large scale and it radiated in many directions helping them in military operations.
Thus they are considered to be pioneers in road construction. In this section we will see in detail about
Ancient roads, Roman roads, British roads, French roads etc.

1.7.1 Ancient Roads

The first mode of transport was by foot. These human pathways would have been developed for
specific purposes leading to camp sites, food, streams for drinking water etc. The next major mode of
transport was the use of animals for transporting both men and materials. Since these loaded animals
required more horizontal and vertical clearances than the walking man, track ways emerged. The
invention of wheel in Mesopotamian civilization led to the development of animal drawn vehicles.

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Then it became necessary that the road surface should be capable of carrying greater loads. Thus roads
with harder surfaces emerged. To provide adequate strength to carry the wheels, the new ways tended
to follow the sunny drier side of a path. These have led to the development of foot-paths. After the
invention of wheel, animal drawn vehicles were developed and the need for hard surface road emerged.
Traces of such hard roads were obtained from various ancient civilization dated as old as 3500 BC.
The earliest authentic record of road was found from Assyrian empire constructed about 1900 BC.

1.7.2 Roman roads

The earliest large scale road construction is attributed to Romans who constructed an extensive system
of roads radiating in many directions from Rome. They were a remarkable achievement and provided
travel times across Europe, Asia Minor, and North Africa. Romans recognized that the fundamentals
of good road construction were to provide good drainage, good material and good workmanship. Their
roads were very durable, and some are still existing. Roman roads were always constructed on a firm
- formed subgrade strengthened where necessary with wooden piles. The roads were bordered on both
sides by longitudinal drains. The next step was the construction of the agger. This was a raised
formation up to a 1 meter high and 15 m wide and was constructed with materials excavated during
the side drain construction. This was then topped with a sand leveling course. The agger contributed
greatly to moisture control in the pavement. The pavement structure on the top of the agger varied
greatly.

In the case of heavy traffic, a surface course of large 250 mm thick hexagonal flag stones were
provided. A typical cross section of roman road is given in Figure 7 the main features of the Roman
roads are that they were built straight regardless of gradient and used heavy foundation stones at the
bottom. They mixed lime and volcanic puzzolana to make mortar and they added gravel to this mortar
to make concrete. Thus concrete was a major Roman road making innovation.

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 Figure 7 Roman road cross section

1.7.3 French roads

The next major development in the road construction occurred during the regime of Napoleon. The
significant contributions were given by Tresaguet in 1764 and a typical cross section of this road is
given in Figure 8. He developed a cheaper method of construction than the lavish and locally
unsuccessful revival of Roman practice. The pavement used 200 mm pieces of quarried stone of a
more compact form and shaped such that they had at least one flat side which was placed on a compact
formation. Smaller pieces of broken stones were then compacted into the spaces between larger stones
to provide a level surface. Finally the running layer was made with a layer of 25 mm sized broken
stone. All this structure was placed in a trench in order to keep the running surface level with the
surrounding country side. This created major drainage problems which were counteracted by making
the surface as impervious as possible, cambering the surface and providing deep side ditches. He gave
much importance for drainage. He also enunciated the necessity for continuous organized
maintenance, instead of intermittent repairs if the roads were to be kept usable all times. For this he
divided the roads between villages into sections of such length that an entire road could be covered by
maintenance men living nearby.

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 Figure 8 French road cross section

1.7.4 British Roads

The British government also gave importance to road construction. The British engineer John
Macadam introduced what can be considered as the first scientific road construction method. Stone
size was an important element of Macadam recipe. By empirical observation of many roads, he came
to realize that 250 mm layers of well compacted broken angular stone would provide the same strength
and stiffness and a better running surface than an expensive pavement founded on large stone blocks.
Thus he introduced an economical method of road construction. The mechanical interlock between the
individual stone pieces provided strength and stiffness to the course. But the inter particle friction
abraded the sharp interlocking faces and partly destroy the effectiveness of the course. This effect was
overcome by introducing good quality interstitial finer material to produce a
Well-graded mix. Such mixes also proved less permeable and easier to compact. A typical cross section
of British roads is given in Figure 9.

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 Figure 9 British road cross section

1.7.5 Modern roads

The modern roads by and large follow Macadam’s construction method. Use of bituminous concrete
and cement concrete are the most important developments as shown in Figure 10. Various advanced
and cost-effective construction technologies are used. Development of new equipment’s help in the
faster construction of roads. Many easily and locally available materials are tested in the laboratories
and then implemented on roads for making economical and durable pavements.

Figure 10 Modern roads cross sections

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1.8. Modes of Transportation

Before invention of wheel, one group of early man would remain isolated from other communities.
They could move only in a walking distance area. The invention of wheel had changed the early man
life, entirely. His social region had also expanded, with time. As time passed by, early man changed
to a civilized person and refined the design of wheels. Earlier, it was made with wood but nowadays,
rubber and steel used to make better wheels and we have also improved to better Means of
Transport now. Bullock carts and pony of earlier time are now replaced by buses, cars, scooter, cycle
etc. Earlier, man could only ride on horses, elephant, camel, bullock cart and handmade boats but we
can also travel in air and space now.

Humans being has always remained surrounded by the three basic mediums as land, water, and air.
Thus the modes of transportation are also connected with these three mediums. Land has given scope
of road and rail transport, while water and air have developed waterways and airways respectively.
Thus there are four different modes of transportation as follows.

• Roadways
• Railways
• Waterways
• Airways
1.8.1 Roadway’s
Roadways are means of transportation on land. It not only includes modern highway system, but also
the city streets, feeder roads and village roads, catering for a wide range of vehicles and the pedestrians.
Transportation by road is the only mode of which can give maximum service to one and all. This mode
of transportation has the maximum flexibility for travel with respect to route direction, time and speed
of travel etc. It is possible to provide door to door service by this mode of transportation only.

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 Table 1: Advantage and disadvantages of Roadway system
S.No Advantages Disadvantages
1 Less capital outlay Seasonal nature
2 Door to door service Accidents and breakdown
3 Service in rural areas Unsuitable for long travel and bulky traffic
4 Flexible service Slow speed
5 Suitable for short travel Lack of organization
6 Lesser risk of damage in transit
7 Saving in packing cost
8 Rapid speed
9 Less cost
10 Private owned vehicles
11 Feeder to other modes of transport

1.8.2 Railways
Railways are steel tracks laid on the ground, over which the trains move. Railways have been
developed for long as well as short distances and for urban travels. Transportation by railway system
is advantageous for longer distances. The railway system could serve as arteries for transportation by
land and the road system as a feeder system for transportation to the interior parts and to the
intermediate localities between two railway stations
The train can move at much higher speeds than pneumatic tire vehicles on modern highways. Steel
track can also take heavy axles load about three to four times heavier than road.
Table 2: Advantage and disadvantages of Railway system

S.No Advantages Disadvantages

1 Better organized Huge capital outlay
2 High speed over long distance Lack of flexibility
3 Suitable for bulky and heavy goods Lack of door to door service
4 Cheaper transport Monopoly
5 Safety Lack of organization
6 Larger capacity Unsuitable for short distances and small loads
7 Public welfare Booking formalities
8 Administrative facilities of Govt No rural service

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1.8.3 Airways
Aircrafts and helicopters use the airways. Air system of transportation is the fastest and provides more
comfort apart from saving time in transportation men and material, but it is costliest among all the
other systems. Due to its high cost, this mode of transportation is confined to Government officials
and rich people.
Table 1: Advantage and disadvantages of Airway system

S.No Advantages Disadvantages

1 High speed Very costly
2 Comfortable and quick service Small carrying capacity
No investment in construction of
3 Uncertain and unreliable
tracks
4 No physical barrier Breakdowns and accidents
5 Easy access Large investment
6 Emergency service Specialized skill
7 Quick clearance Unsuitable for cheap and bulky goods
Most suitable for carrying light
8 Legal restrictions
goods of high value
9 National defense

1.8.4 Waterways
This mode of transport includes oceans, rivers, canals and lakes for the movement of ships and boats.
In this system ships and boats are used to transport men and material. Transportation by this system is
possible between the ports on the sea route or along the river or canal where inland navigation facilities
are available. Though the speed of this system is lowest among the all four system but it need minimum
energy to haul unit load through unit distance.
Apart from these four system of transportation pipe lines are also used for transportation of water, gas,
and crude oil etc. As minor transportation system, elevators, cable cars, aerial rope ways, belt
conveyors etc are also used.
1.9 Future Developments

The modern phenomena of growing populations and increased urbanization increase demands on
sustainable and efficient urban transport solutions. Such solutions must address traffic safety, reduce
accidents and help avoid congestion, and by doing so also reduce emissions. One key aspect is also
the emerging need for efficient public transportations. The future transport solutions for urban areas
are.

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 • Bus Rapid Transit System (BRTS),
• Mass Rapid Transit System (MRTS)
• Intelligent Transport Systems (ITS)

1.9.1 Bus Rapid Transit System (BRTS)

BRTS is a high performance public transport bus service. BRTS is a highly efficient public transport
concept designed to meet growing transport demands in cities around the world. Bus Rapid Transit
Corridor or BRT means giving right of way to buses and safeguarding cyclists and pedestrians by
encouraging lane driving on engineered road spaces along large and wide corridors and link them to
metros and other colony roads for easy access. The key elements of BRT are:

• Dedicated Central Lanes

• Quicker Travel
• Reduced conflicts with cycles and other vehicles
• Station-Bus Interface
• Easy boarding to the bus
• Passenger Information
• In Station: destination and arrival time on next bus
• In Buses: next station announcement
• Affordable fares and Efficient Fare Collection
• Integration with other public transit modes (metro, buses, rickshaws, rail).

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 Figure 11 BRTS system

1.9.2 Mass Rapid Transit System (MRTS)

(Underground, subway, elevated railway, metro or metropolitan railway) is a passenger transport

system in an urban area with a high capacity and frequency, and grade separation from other traffic.
Rapid transit systems are typically located either in underground tunnels or on elevated viaducts above
street level. The trains are electrically powered, usually by third rail, and their railroads are separate
from other traffic, usually without level crossings. Usually they run in tunnels in the city Centre and
sometimes on elevated structures in the outer parts of the city. They can accelerate and decelerate faster
than heavier, long-distance trains.

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 Figure 12 MRTS/Subway system

1.9.3 Intelligent Transport Systems (ITS)

Enables elements within the transportation system - vehicles, roads, traffic lights, message signs, etc.
- to become intelligent by embedding them with microchips and sensors and empowering them to
communicate with each other through wireless technologies. The core of ITS consists in obtaining,
processing, and distributing information for better use of transportation system, infrastructure and
services. ITS is a concept that will contribute to the more efficient use of infrastructure and transport
solutions in the future. Transport systems can reduce impact on the environment, and increase safety
and security through real-time traffic information, remote monitoring, and communication between
transport vehicles and the infrastructure. Some ITS Technologies used in Public Transport are

• Real-time passenger information/ Public Transport Travel Information

• Smart Card Based Fare Collection/ Electronic Ticketing
• Surveillance/ CCTV/ Security Systems.

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Figure 13 ITS system

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