2. Urban Roads
• ‘A man is known by the company he keeps’.
In a similar manner, a city or a town is
admired by its road system.
• A well arranged layout of a town is spoiled, if
it does not contain a well – designed road
pattern connecting the various parts of the
town. The town planner should therefore
give careful considerations to the design
provisions of street in the town.
4. Urban Roads
• The urban road play an important role in
the development of town or city and as such,
they attract many evils such as heavy traffic
congestion, ribbon development, etc.
• If properly attended to by the town
planner. It is very difficult, if not
impossible, to alter the existing road system at
a later stage except at very high cost.
6. Urban Roads
• The parks, playgrounds, green open spaces
and gardens are the lungs of the town and
the roads or streets plan is considered as the
foundation of the town plan.
• The efficiency of an urban area is greatly
influenced by the urban infrastructure of
roads together with public services.
8. Objects of Urban Road
The main object of Urban roads are as follows:
• To facilitate Communication of men and
materials between the various centres of the
town.
• To provide air and light to the properties
situated on their edges;
• To provide space for laying the public utility
services like water mains; drainage pipe, electric
cables, telephone lines. Etc.
12. Requirements of a Good City Road
Following are the ideals which are to be kept
in while designing a good city road;
• It should accommodate amenities such as
shady avenues, Parking places, enough
lighting etc.
• It should be cheap and Durable.
• It should be resting on unyielding soil.
• It should have good alignment and visibility.
16. Requirements of a Good City Road
• It should possess easy gradients and smooth
curves.
• It should possess well designed junctions.
• It should remain in dry conditions.
• It should avoid traffic congestions
• Its wearing surface should be impervious
• Its width of camber should be proper
20. Factors to be Considered
• Following are the factors which are to be
considered by a town planner while designing a
town road.
1) Destination
• The points or centre or areas which are being
linked up by the road are to be studied with
respect to their capacity of attracting traffic.
2) Importance of Road
• The Overall Importance of Road with respect
to the surrounding roads is to be ascertained and
accordingly, the facilities and dimensions are to
be determined.
23. Factors to be Considered
3) Nature of Traffic
• The probable traffic to be carried by road is
studied with respect to its intensity, peak
period, types of vehicles, parking facilities.
4) Use of Road
• The probable use to which the road is to be
put up for maximum period during the day
is to be properly estimated.
25. Classification of Urban Roads
• The Urban Roads are classified into the following five
categories;
• Expressways
• Arterial Roads
• Sub-Arterial Roads
• Local Roads
• Streets
• Pathways
Each of the above category of road well be explained
below
26. Expressways
• The purpose of expressways is to cater for
mobility of large volume of motor traffic at
high speed.
• Divided highway with high standards of
geometrics
• Full or partial control of Access
• Provided with Grade Separation Intersection
• Vehicle parking, loading and unloading of
products and passengers and pedestrian traffic
are not allowed on these kinds of highways
28. Arterial Roads
• The roads that connects the town to a state
highway or a national highway is termed as
arterial road. It passes within the city limits
and carries great masses of traffic between
different parts of the town.
• The arterial road include ring roads, by-pass
roads, etc, and they allow free movement of fast
traffic at higher speeds.
• These roads are also kept clean of all
obstruction such as frontage of building, parking
places, loading and unloading areas,
30. Arterial Roads
• The arterial road should serve the following
three purpose
• The movement and safety of through traffic i.e.
traffic moving beyond its point of origin
• There is some economy in construction in the
sense that only arterial routes are designed to
carry heavy traffic and other types of roads.
• The through traffic is not allowed to pass
through residential areas. Hence, the discomfort
and danger to the residents of such area is
minimized.
32. Sub Arterial Roads
• These roads are also known as the major
roads or secondary roads. They are
contained within city limits and they
connect important town centres.
• These roads serve slow moving traffic over
short distances . The intersection on these
roads are provided with suitable traffic
signals.
35. Local Roads
Local Roads
• These roads are also known as minor roads.
They collect Traffic from various parts of the
town and lead it to another minor or major
road. These roads give access to abutting
properties and importance is given to the non
vehicular traffic on the roads.
• The local roads are not allowed to touch or to
come in contact with the arterial roads and the
two are separated by a bridge and one goes
over the another
37. Streets
Streets
• A road which serves the need of an internal
portions of a local area is known as street. The
portion to be served may either by residential,
Commercial, or Industrial.
• The design of street is made after considering
the purpose and use of the portion to be served
by the street and special attention is paid to the
social, commercial and other requirements of
the local community.
39. Pathway
Pathway
• These are also known as the pedestrian
ways and they are in the form of accesses
leading to individual shops or premises. The
vehicular traffic is no allowed to move on the
pathway
41. Types of Street System
The street systems are classified as
• Rectangular Street System
• Rectangular with superimposed diagonals street
system
• Concentric Street System
• Radial Street System
• Combined of Radial or Rectangular Street System
• Irregular medieval street system
• Topographical Street System
• Combination of Rectangular and irregular Street
System
42. Rectangular Street System
• In this pattern, the streets are usually of
equal width and they cross at right angles. It
is also known as Grid- Iron, or chequer-
Board Pattern. This pattern is suitable for flat
country without any predominant natural
feature. The example of this system are
Philadelphia and Jaipur.
45. Advantages Of This Pattern
• If series of parallel lines are provided it
results in increase of traffic capacity.
• It grants comfort and convenience due to its
regularity.
• The intersection is simple in nature.
• It results in economic construction.
• The wastage of land can be minimized as
there is no irregular portion to be left out.
46. Disadvantages
• As there are many intersections, there are
more chances of Road Accidents.
• If this pattern is applied on uneven
topography, it leads to great inconvenience
and discomfort.
• It is to mathematical and monotonous
because the roads are straight and there is no
variety.
48. Rectangular With Superimposed
Diagonal Street System
• This arrangement is an improvement on
Grid Iron Pattern. The diagonal Street
Provides direct communication between
distant parts of the street.
• The point where diagonals meet are utilized
for park, garden, memorial etc, However, a
dangerous intersection is formed at the
crossing point of diagonal street and
rectangular street.
50. The Features Of This System Are :
• The Circle, squares, and other open spaces
at junction of street and avenues are
profitable utilized as sites for gorgeous
statues, monuments and fountains.
• The public building are provided with
enough open spaces all around them.
• The streets are very wide and are well
planted with trees.
51. Concentric Street System
• In this system the ring roads or circumferential
roads are connected with radial roads.
• This patter is also known as Spider’s Web
System.
• The concentric ring is developed mainly due to
removal of encircling walls and fortification.
However if the radial roads are not well
developed the central part they will overload at
the central part of the town.
54. Radial Street System
• In this pattern, the ring roads spring from
the central civic centre like the spokes of a
wheel.
• Such an arrangement increases the
significance and importance of civic centre
which may be in the form of palace, market,
public office buildings, historical
monument, beauty spots, etc.
56. Combination Of Radial And
Rectangular Street System
• In this arrangement, the radial streets are
blended or mixed with rectangular streets
such a combination can be used with great
success especially where topographical
features are favorable.
59. Irregular Mediaeval Street System
• Some of the old Cities of middle ages
developed in an irregular ways without any
definite plan of the street system, possess
this type of System.
• The growth of town or city is unmethodical
and illogical. The mediaeval street patterns
naturally does not efficiently serve the modern
traffic and such towns are referred as
mediaeval towns.
61. Topographical Street System
• In this arrangement, the advantage is taken of the
natural topography feature of the town such as
river, lake, sea view, hillock, etc.
• This system is also known as the organic Street Pattern
as it resembles the plan on microscopic slide showing
the cell structure of vegetable or animal tissues.
• The street system is absolutely unplanned, The
street pattern, however becomes pleasing and
attractive only if it is conformity with topography of
the area and natural surrounding.
64. Combination of Rectangular and
Irregular Street Systems.
• In this arrangement a combination of
rectangular pattern and irregular street is
made. The rectangular layout indicates the
recent development and the irregular
pattern indicates earlier growth of town.
When it is difficult or too costly to improve the
existing irregular street system, a combination
is formed the outstanding example of this
system is Edinburgh (U.K)
66. Thorough And Bypass Roads
• When a through road or a main road passes
through the congested portion of the town,
there is sharp reduction in the speed of
vehicles and the smooth flow of traffic or
through road is seriously obstructed. To
maintain easy flow of traffic on through roads
and to give convenience and comfort to the
users of such roads
67. Thorough And Bypass Roads
• These by-pass roads are also known as the loop
roads and they avoid the traffic on through roads to
avoid congested area of the town, at suitable points
along the main road, the vehicles are diverted by the
bypass roads from one side come on the through
road on the other sides after passing the congested or
habitated areas of the town.
• The provision of a by-pass road results in the
reduction in traffic through the congested areas of a
town, chances of accidents are minimized.
70. Outer and Inner Ring Roads
• The Object of an Outer Ring Road is to divert
from the town all the through traffic which has
no business in the town
• It is a type of bypass road for traffic
approaching the town from all the directions.
All classes of wheeled traffic will be admitted on
the outer ring road and the pedestrians should be
maintained clean of all existing development and
it should be so designed so as to compensate for a
longer route by unbroken passage and high speed.
73. Expressways
• The term expressway is used to indicate an arterial road
on which fast urban traffic is allowed to move speedily
and safely, It allows through traffic with full or partial
control and generally with grade separation at
intersections. The design of these expressways include easy
gradients and smooth curves.
• The provision of expressway around big cities relieves to
a certain extent the traffic congestion and they provide
easy flow of traffic.
• The expressway do not form the part of the regular
street system. The only prohibitive part of expressway is
the tremendous cost and hence, it is adopted for big
metropolitan cities
75. Freeways
• The mere widening of an arterial road will not often
relieve crowding due to traffic. This creates the need for
constructing special routes that will serve only fast
moving traffic and will not be subjected to interferences
from vehicles going to and from the building fronting
the arterial roads.
• The freeway is the latest answer for satisfying the demand
of special routes which provide an express route for both the
types of vehicles, passengers as well as commercial.
• A freeway is thus defined as high class arterial road
having controlled access or in other words, it is an
expressway with full control of access
78. The Essential Features Of Express
way
Access from adjacent properties:
• In case of a freeway, the access from adjacent
properties is totally denied and it results into
no need for parking.
Design and Construction
• It is designed in such a way that it can carry
maximum volume of traffic with the highest
degree of safety.
80. The Essential Features Of Express
way
Entrance and exits;
• To give connection to the street systems, of the town,
the entrance and exits on the freeway should be
provided at infrequent intervals.
Location:
• In general, the freeway would pass around rather
than through a city
• Traffic Control: The key of effective traffic control on
freeway lies in getting early information and proper
analysis of the same. It is thus seen that the freeways
have got the ability to carry high volume of traffic at
relatively high speed.
82. Precincts
• The word precincts was originally used for
enclosed space surrounding a church, but
now it is used in the town planning to
indicate an artificial enclosed space formed by
the arterial roads and sub arterial roads. It is
the quite area of the building in which
traffic is not allowed.
84. Precincts
• The features of precinct are
• All the road within a precinct are strictly local
roads
• Each precinct is planned and is developed as a
distinct unit of residence.
• The building within a precinct do not face
towards arterial and sub arterial road.
• The connection between the road system of the
precinct and sub arterial road are few.
• It diverts noise and bustle of the traffic.
86. Road Aesthetics
• To keep the road beautiful and pleasing the
following principles are observed:
• Sincere efforts should be made to present
decent and pleasing views along the route
followed by the road.
• The curves along the road should be smooth
and easily negotiable.
• The footpath should be provided with concrete
and stone kerb.
• The ornamental lighting with proper space
should be installed along the road.
89. Road Aesthetics
• The road should be provided with side drains
to dispose of rain water.
• The road should be maintained neat and clean.
• The traffic Islands should be given some
artistic touch by providing statue, fountain,
monument.
• The tree grown along the road side should be
properly maintained.
• Wherever, possible road arboriculture should
be encouraged.
