Unit 9 ( TRAFFIC CONTROL DEVICES AND ROAD FURNITURE ( Part 1 ) )

Traffic Control Devices and Road Furniture

Highway Engineering C3010 / UNIT 9

TRAFFIC CONTROL DEVICES AND

ROAD FURNITURE

( Part 1 )

OBJECTIVES

General Objective

To understand the general information of traffic control device and road furniture.

Specific Objectives

At the end of the unit you should be able to :- state the type of traffic control devices.. identify the meaning of the symbol and color is used. describe the characteristic of traffic devices.

UNIT 9UNIT 9



9.0INTRODUCTION

Before highway is opened to traffic, careful thought must be given to

conveying to drivers information concerning its proper use. Such information is

given traffic control devices.

Engineer must also recognize that despite their best efforts to promote

well-designed traffic control systems, vehicles will occasionally go out of

control and possibly crash. Every effort must be made to prevent traffic

accident from occurring and, failing that, to minimize the injuries and

economic losses from those crashes that do occur.

Street and highway traffic constitutes a variety of road users desirous of

moving at different speeds. This demand for moving according to individual

desire leads to resistance to movement by others thereby creating accident

hazards particularly in areas where there is no provision for segregation of traffic

of different types or where directions of movement conflict with one another. To

avoid this situation become worst, traffic control devices are needed to decrease

the accident happen.

In this unit, we will examine ways in which traffic engineers promote

operation efficiency and safety through the use of traffic control devices and

systems.

INPUT

TRAFFIC CONTROL DEVICES – TRAFFIC SIGN & ROAD MARK



9.1 TRAFFIC CONTROL DEVICES

Traffic control devices should be reasonable and appropriate for

the traffic requirements at the location used. The use of a traffic control

device at a location where it is not warranted tends to invite motor-

vehicle operators to disregard the device and to have less respect for

traffic control devices in general.

Traffic control devices should be properly designed. The size of

the device, its shape, colors, contrast with the background, and lighting

or re-flectorization should draw attention. The sign, marking, or signal

should simply and forthrightly convey a clear and simple message. The

use of uniform devices following the MUTCD (Manual on Uniform Traffic

Control Devices For street and Highway) simplifies the driver's task of

recognizing and understanding the traffic control messages and tends to

increase the level of observance.

The Government has adopted the following color code for traffic

control devices.

Color Meaning

Red

Green

Blue

Yellow

Black

White

Orange

Brown

Stop or prohibition

Indicated movements permitted, direction guidance

Motorist services guidance

General warning

Regulation

Regulation

Construction and maintenance warning

Public recreation and scenic guidance



Traffic control devices should be placed and operated in a uniform,

consistent manner. In this way, motorists can be expected to properly

respond to the devices on the basis of previous exposure to similar traffic

situation. A control device should be placed within the user's cone of vision

and in reasonable proximity to the point, object, or situation to which it

applies. Its location and legibility should be such that a driver traveling at

normal speed has enough time to respond appropriately.

It is important that devices be maintained to high standards to

ensure that legibility and visibility are retained. When no longer needed,

traffic control devices should be removed.

Traffic control devices are needed to control the traffic flow to effective

system. The traffic control devices, which are usually employed for the controls

of traffic is briefly discussed blow.

1. Traffic Sign.

2. Road Mark.

3. Delineator.

4. Road Stud.

9.2 PURPOSE OF TRAFFIC CONTROL DEVICES

Traffic control devices serve one or more of the following purposes;

1. Convenient for the user to reach the destination.

2. Safety of the traffic user.

3. To avoid traffic conflict in a very complex area.

4. Smoothness the process of traffic flow.



9.3 CHARACTERISTIC OF TRAFFIC CONTROL DEVICES

In order to provide safe and efficient traffic flows, uniform standards

have been developed for the use of all public street and highway facilities.

Traffic control devices include all signs, markings, and signals placed on or

adjacent to street or highway by public agencies in order to regulate, warn,

or guide traffic. If traffic control devices are to be effective, they should

1. Fulfill a need.

2. Command attention.

3. Convey a clear, simple meaning.

4. Command respect of drivers and pedestrians.

5. Be place so as to give users time for proper response.

9.4 TRAFFIC SIGNS

There are three functional classes of traffic signs:

1. Mandatory signs

2. Prohibitory signs

3. Warning signs.

4. Informatory signs.

9.4.1 CLASSIFICATION TRAFFIC SIGNS

1. Mandatory signs

Mandatory signs give users notice of traffic laws or

regulations. Such signs, designate right-of-way (e.g.,



STOP), indicate speed control ( e.g., SPEED LIMIT 60

km/j, SPEED ZONE AHEAD), control movements (e.g.,

NO RIGHT TURN, KEEP RIGHT, ONE WAY), regulate

parking (e.g., NO PARKING), control pedestrian

movements (e.g., CROSS ONLY AT CROSS WALKS),

and regulate traffic in various other ways. All mandatory

signs are appearance circle and white symbol as

background blue or another comfortable color.

2. Prohibitory signs

Prohibitory signs showing to all drivers about matter which

cannot they do. For example, no u-turn, no waiting and no

unload, no parking and prohibitory weight especially for car,

size car and height. This signs ordinary appearance circle

shape.

3. Warning signs

Warning signs direct attention to conditions on or

adjacent to a street or highway those are potentially

hazardous to traffic operations. Such signs require

motorists to exercise caution, reduce speed, or make

some maneuver in the interest of their own safety or that

of other motorists or pedestrians. Typical locations or

situations that may warrant the use of warning sign

include;

1. Intersections, entrances, and crossings.



2. Changes in horizontal alignment.

3. Grades.

4. Railroad crossings.

5. Narrow roadways.

6. Roadway surface Conditions.

7. Advance warning of control devices.

Examples of warning signs are curve signs

(showing curved arrow), STOP AHEAD signs,

PAVEMENT ENDS signs, and advisory speed plates.

The latter signs supplement other types of warning

signs. Warning signs have a black legend and border

placed on a yellow background. With but few

exceptions, warning signs have a diamond shape.

4. Informatory signs

Guide signs indicate route designations, directions,

distances, point of interest, and other geographic or

cultural information. Two types of guide signs (route

markers and a destination sign) are illustrated by Figure

below,

Other examples of guide signs include JUNCTION

signs, DETOUR signs, REST AREA signs, and service

signs (FOOD, GAS, LODGING, etc ). Sign board like this

normally provided with color blue as background and symbol

or white which write by hand.



9.5 ROAD MARKING

Road marking are definitely as lines, symbols, words, numbers or others

material that painted or paste on the surface of the road. Different from the sign

boards, road sign material giving the interminable to the vehicles guide.

Markings consist of paint or some other material placed on the

pavement, curb, or object to convey traffic regulations and warnings to

drivers. Making may be used alone or in combination with traffic signs or

signals. Although markings are an effective and essential means of traffic

control, they tend to see in rainy weather and fair day.

There are five general classes of markings:

1. Pavement marking.

2. Curb markings.

3. Object markings.

4. Delineators.

5. Colored pavement.

The most common type of markings, pavement marking, include

longitudinal and transverse line and words and symbols. By choice of

color, width, and type of longitudinal marking, the traffic engineer is

able to convey a variety of massages to drivers. Briefly stated,

1. Broken lines are permissive in character; solid lines are

restrictive; double line indicate maximum restrictiveness.



2. White lines delineate separation of traffic flows in the same and

opposing direction; yellow lines delineate no parking area at the

both side of road.

3. The width of the line indicates degree of emphasis.

Transverse markings include pedestrian crosswalks, stop lines,

and crosshatched to discourage use of shoulders or to identify object

hazards. Curb markings are used for roadway delineation and for

parking regulation. Color-coded markings may be used as a

supplement to standard signs to indicate the type of parking

regulation.

9.5.1 The Type Of Road Mark

The types of the road mark are commonly used :

1. Middle line

2. Passage line

3. Double line

4. Arrow

5. Desist line

6. Pedestrian crossing line

7. Yellow line at side road

9.5.2 The Materials Of Road Mark

The materials of road sign must be durable and light reflective

properties. So normally used as road materials are :

1. Thermoplastic

2. Paint



3. Road studs/ cats eye

Thermoplastic and paint are normally used in small town,

thermoplastic and paint is used as middle line and passage line in a big

city, it use as pedestrian crossing line and desist line.

TEST YOUR UNDERSTANDING BEFORE YOU CONTINUE WITH THE NEXT

INPUT

1. Choose the correct meaning of the color code for traffic control

devices as listed below.

Color code Meaning

Red Indicated movements permitted, direction guidance

Yellow Stop or prohibition

White Motorist services guidance

Blue Public recreation and scenic guidance

Black Construction and maintenance warning

Orange Motorist services guidance

Brown Regulation

Green Regulation

ACTIVITY 9

Question



2. State five general classes of road markings:

1.

Color code Meaning

Red Indicated movements permitted, direction guidance

Yellow Stop or prohibition

White Motorist services guidance

Blue Public recreation and scenic guidance

Black Construction and maintenance warning

Orange General warning

Brown Regulation

Green Regulation

2. There are five general classes of markings:

6. Pavement marking.

7. Curb markings.

8. Object markings.

9. Delineators.

FEEDBACK ON ACTIVITY 9

Answer



10.Colored pavement.

1. Describe briefly about the traffic control devices which are usually

employed for the controlling the traffic.

2. State 4 purposes of the traffic control device.

3. Describe the following aspects: -

a. Prohibitory sign.

b. Warning sign.

c. Mandatory sign

Question



1. Traffic control devices should be reasonable and appropriate for

the traffic requirements at the location used. The use of a traffic

control device at a location where it is not warranted tends to invite

motor-vehicle operators to disregard the device and to have less

respect for traffic control devices in general.

Traffic control devices should be properly designed. The size of the

device, its shape, colors, contrast with the background, and lighting or re-

flectorization should draw attention. The sign, marking, or signal should

simply and forthrightly convey a clear and simple message. The use of

uniform devices following the MUTCD (Manual on Uniform Traffic Control

Devices For street and Highway) simplifies the driver's task of recognizing

and understanding the traffic control messages and tends to increase the

level of observance.

Answer



Traffic control devices should be placed and operated in a uniform,

consistent manner. In this way, motorists can be expected to properly

respond to the devices on the basis of previous exposure to similar traffic

situation. A control device should be placed within the user's cone of vision

and in reasonable proximity to the point, object, or situation to which it

applies. Its location and legibility should be such that a driver traveling at

normal speed has enough time to respond appropriately.

It is important that devices be maintained to high standards to

ensure that legibility and visibility are retained. When no longer

needed, traffic control devices should be removed.

Traffic control devices are needed to control the traffic flow to effective

system. The traffic control devices, which are usually employed for the

controls of traffic is briefly discussed blow.

a. Traffic Sign.

b. Road Mark.

c. Delineator.

d. Road Stud.

2. Traffic control devices serve one or more of the following purposes;

a. Convenient for the user to reach the destination.

b. Safety of the traffic user.

c. To avoid traffic conflict in a very complex area.

d. Smoothness the process of traffic flow.

3.



Mandatory signs

Mandatory signs give users notice of traffic laws or

regulations. Such signs, designate right-of-way (e.g., STOP),

indicate speed control ( e.g., SPEED LIMIT 60 km/j, SPEED

ZONE AHEAD), control movements (e.g., NO RIGHT TURN,

KEEP RIGHT, ONE WAY), regulate parking (e.g., NO

PARKING), control pedestrian movements (e.g., CROSS

ONLY AT CROSS WALKS), and regulate traffic in various

other ways. All mandatory signs are appearance circle and white

symbol as background blue or another comfortable color.

Prohibitory signs

Prohibitory signs showing to all drivers about matter which

cannot they do. For example, no u-turn, no waiting and no unload,

no parking and prohibitory weight especially for car, size car and

height. This signs ordinary appearance circle shape.

Warning signs

Warning signs direct attention to conditions on or

adjacent to a street or highway those are potentially hazardous

to traffic operations. Such signs require motorists to exercise

caution, reduce speed, or make some maneuver in the interest

of their own safety or that of other motorists or pedestrians.

Typical locations or situations that may warrant the use of

warning sign include;

1. Intersections, entrances, and crossings.



2. Changes in horizontal alignment.

3. Grades.

4. Railroad crossings.

5. Narrow roadways.

6. Roadway surface Conditions.

7. Advance warning of control devices.

Examples of warning signs are curve signs (showing

curved arrow), STOP AHEAD signs, PAVEMENT ENDS

signs, and advisory speed plates. The latter signs

supplement other types of warning signs. Warning signs

have a black legend and border placed on a yellow

background. With but few exceptions, warning signs have a

diamond shape.

Unit 9 ( TRAFFIC CONTROL DEVICES AND ROAD FURNITURE ( Part 1 ) )

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Transcript of Unit 9 ( TRAFFIC CONTROL DEVICES AND ROAD FURNITURE ( Part 1 ) )