1

A Mini-Project report on

SPOT SPEED AND SPEED DELAY TIME SURVEY

BACHELOR OF TECHNOLOGY

IN

CIVIL ENGINEERING

Submitted By

Ch Venu 12245A0107

Y Sai Santosh 11241A01C0

M Vinod Kumar 11241A0152

Y Hemanth Reddy 11241A0160

B Naveen Reddy 11241A0167

Under the Guidance of

Sri V Srinivasa Reddy

Associative Professor

DEPARTMENT OF CIVIL ENGINEERING

GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND

TECHNOLOGY- AUTONOMOUS

(Approved by AICTE Affiliated to JNTUH- NBA Accredited)

BACHUPALLY, KUKATPALLY HYDERABAD-500090

2014

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Acknowledgement

The satisfaction and euphoria that accompany the successful completion of any

task would be incomplete without the mention of people who made it possible. We wish

to express our deep sense of gratitude towards our Internal Guide Sri V Srinivasa

Reddy, Associative Professor, Civil Engineering, for giving us an opportunity to work

on this project that was very interesting for us.

We would also like to express our deepest sense of gratitude towards Sri V

Gajendra, Associative Professor, Civil Engineering, for helping us to complete our

project successfully.

We would like to place on record my deep sense of gratitude to Dr Mohammed

Hussain, Head of the Department, Civil Engineering for his generous guidance, help

and useful suggestions.

We express a whole hearted gratitude to Dr Jandhyala N Murthy, Principal of

Gokaraju Rangaraju Institute of Engineering and Technology, for providing us the

conductive environment for carrying through our academic schedules and project with

ease.

We are grateful to the staff of our college for providing facilities for completion

of the project. We acknowledge the help of all those who had given encouragement and

associate themselves in one way or the other in completion of the dissertation work.

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CONTENTS

Abstract

List of Figures

List of Tables

List of Graphs

1. Introduction 01-06

1.1 Spot Speed studies 01

1.1.1 Motivation 01

1.1.2 Problem Definition 02

1.1.3 Objectives of spot speed studies 02

1.1.4 Limitations of spot speed studies 02

1.2 Speed Delay Time Survey 03

1.2.1 Motivation 03

1.2.2 Problem Definition 03

1.2.3 Objectives of speed delay time survey 03

1.2.4 Limitations of speed delay time survey 04

1.3 Break Down Structure 05

1.3.1 BDS of Spot Speed Studies 05

1.3.2 BDS of Speed Delay Time Survey 06

2. Literature Survey 07-10

2.1 Introduction 07

2.2 Spot Speed Studies 07

2.2.1 Existing System 07

2.2.2 Disadvantages of Existing system 08

2.2.3 Proposed System 09

2.3 Speed Delay Time Survey 09

2.3.1 Existing System 09

2.3.2 Disadvantages of Existing system 10

2.3.3 Proposed System 10

3. Spot Speed Methodology 11-16

3.1 Introduction 11

3.2 Methods of Spot Speed Measurement 12

3.2.1 Stop Watch Method 13

3.2.2 Pneumatic Tube Method 14

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3.2.3 Doppler-Principle Meter 15

3.2.4 Electronic-Principle Detectors 16

4. Stop Watch Method 17-21

4.1 Stretch Selection Criteria 17

4.2 Experimentation 18

4.3 Data collection 20

5. Calculations and Design 22-34

5.1 Calculations 22

5.1.1 Analytical Calculations(Four Wheeler) 22

5.1.2 Statistical Calculations(Four Wheeler) 23

5.1.3 Analytical Calculations(Two Wheeler) 27

5.1.4 Statistical Calculations(Two Wheeler) 28

5.2 Design of Speed Limit 32

5.3 Recommendations 33

6. Speed and Delay Time Survey 34-37

6.1 Introduction 34

6.2 Methods of Speed Delay Time Survey 34

6.2.1 Floating Car Method 35

6.2.2 License Plate Method 36

6.2.3 Interview Technique 37

6.2.4 Elevated Observer Method 37

7. Floating Car Methodology 38-40

7.1 Stretch Selection Criteria 38

7.2 Experimentation 38

7.3 Data Collection 40

8. Speed Delay Time Survey Calculations 41-42

9. Discussions and conclusions 43

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Abstract

Designing and construction of a road involves estimation of traffic volume and

setting up ideal speed for the vehicles to travel in a comfortable way. Now days, due to

rapid increase in volume of traffic the designed speed on high ways could not be

maintained resulting a delay in reaching target point.

Our project also involves survey of spot speed of vehicles near a school zone.

This helps us to recommend changes to the existing system. These recommendations may

involve establishment of precautionary sighs like school zone, speed limit etc.

Our project is to study the traffic volume and check the time to reach the target in

off-peak and peak timings on a high way stretch (say from JNTU to Lingampally) and

coming up with both analytical and practical solution under IRC guidelines. The

conclusion of the project is the solution to problems faced inNH-9 journey by checking

personally and taking feedback of public using the highway.

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List of Figures

1. Spot speed survey BDS 05

2. Speed delay time survey BDS 06

3. ZENAS International School 08

4. Pictorial representation of stop watch method 13

5. Pneumatic road tube method 14

6. RADAR method 15

7. Photography method 16

8. First and Third observer recording the time of travel 19

9. Second observer signaling that the test vehicle crossed the section 19

10. School zone board 33

11. Map showing starting and destination points-speed delay time survey 39

List of Tables

1. Guideline for selecting stretch length 18

2. Spot speed observations(Four wheelers) 20

3. Spot speed observations(Two wheelers) 21

4. Frequency distribution(Four wheelers) 23

5. Frequency distribution(Two wheelers) 28

6. Guidelines for establishing speed limits 32

7. Speed delay time survey observations 40

List of Graphs

1. North bound frequency curve(Four wheelers) 24

2. Frequency distribution curve(Four wheelers) 25

3. Cumulative frequency curve(Four wheelers) 26

4. North bound frequency curve(Two wheelers) 29

5. Frequency distribution curve(Two wheelers) 30

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6. Cumulative frequency curve(Two wheelers) 31

Chapter-1

INTRODUCTION

Traffic Engineering is that branch of engineering which deals with the

improvement of traffic performance of road networks and terminals. This is achieved by

systematic traffic studies, scientific analysis and engineering applications. Traffic

engineering deals with the application of scientific principles, tools, techniques and

findings for safe, rapid, convenient and economic moment of people and goods. The

basic object of traffic engineering is to achieve efficient free and rapid flow of traffic

with least number of traffic accidents. Factual studies of traffic operations provide the

foundation for developing methods for improvement in general and for solving specific

problems. These studies help in deciding the geometric design feature and traffic control

for safe and efficient traffic moments.

Speed is an important transportation consideration because it relates to safety,

time, comfort, convenience and economics. The actual speed of vehicles over a particular

route may fluctuate widely depending on several factors such as geometric features,

traffic conditions, time, place, environment and driver.

1.1 Spot speed studies

1.1.1 Motivation

The profession of traffic engineering as known today has evolved with the advent

of motor vehicles. During the last few decades significant advances have been made in

many phases of the profession. Advance study and training facilities have been made

available at several universities and institutions. Traffic engineering has now been

recognized as an essential tool in the improvement of traffic operations in metropolitan

cities like Bombay, Calcutta, and Madras. Study of speed characteristics is the most

essential perquisite for any improvement of traffic facilities.

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1.1.2 Problem Definition

In present scenario due to heavy traffic volume, the existing roads are insufficient

to maintain the design speed. With the help of spot speed studies we can manage the

traffic volume by diversion or by designing signal cycle time.

1.1.3 Objectives of Spot Speed Study

Spot speed survey is conducted to

i) To establish speed limit in a school zone near Zenus International School, Hydernagar.

ii) To recommend Zebra crossing or pedestrian signal if necessary.

iii) To recommend caution signs in the school zone

iv) To compare diverse types of drivers and vehicles under specified conditions

1.1.4 Limitations of the study

• The spot speeds are affected by physical features of the road like Pavement width,

curve sight distance, gradient, Pavement unevenness, intersections, and road side

developments.

• Other factors affecting spot speeds are environmental conditions, enforcement,

traffic conditions, driver, vehicle and motive of travel.

• The greatest disadvantage is that the progress is as slow as it is difficult to spot

out typical vehicles and number of vehicles observed will be less.

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• There is a possibility of human error.

1.2 Speed delay time survey

1.2.1 Motivation

Due to the fact that delay at signalized intersections is of particular interest, many

efforts are put on the intersection delay study. Accurate estimation of delays has many

implications in traffic engineering studies. Transportation planners will use delay to

evaluate economic loses, whereas traffic engineers will use delays to determine level of

service at signalized intersections. In general the methodology used in analyzing

intersection delay comes from the HCM (Highway Capacity Manual).

1.2.2 Problem Definition

Due to congested roads at peak hours, Public faces speeding problems, this may

also lead because of traffic jams, accidents, bad traffic management etc.., Travel time

plays key role in city’s life and it indicates the level of service of roadway network

performance. From mobility point of view travel time reflects degree of convenience

from one point to the other point.

1.2.3 Objectives of Speed Delay Time Survey

• To determine running speed, overall speed, Fluctuation in speed and to find out

delay time between two stations of a road spaces apart.

• To gather the information such as amount, location, duration frequency and the

causes of the delay in the traffic stream.

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• To determine the spots of congestion and causes and in-arriving at a suitable

remedial measures.

• To find the travel time, average journey time, and benefit-cost analysis.

• To rate the efficiency of a road.

1.2.4 Limitations of Speed Time Delay Survey

• This survey requires more man power

• There is a possibility of human error

• For accurate results more number of experimental trips may be carried out

• Data collected may not show the complete features of the road and may not be

accurate because of fluctuating traffic flow time-time

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1.3 Break Down Structure

1.3.1 Spot Speed Studies BDS

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Fig 1: spot speed survey BDS

1.3.2 Speed Delay Time Survey

Fig 2: speed delay time survey BDS

Determine study parameters

Collection of Data

Analyses of Data

Experimentation

Calculations

Discussions &

recommendations

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Chapter 2

Literature Survey

2.1 Introduction

The idea of doing this project is because of the traffic problem that every metro

Politian city is facing today in India. Our team decided to take up one problem in the city

and find out a solution that is feasible, economic, and easily adoptable. The one problem

that we can think of while was traffic jams that consume heavy time. Causes for the

traffic jam may be in-adequate roads, heavy traffic volume, in-efficient signal system,

bad traffic management, etc..,. School premises comes under a separate speed zones,

many precautions need to be taken near a school like establishing speed limit, and

precautionary zone, zebra crossing, and providing pedestrian signal if necessary.

Our study may be divided into two parts, one is determining spot speed of

vehicles near a school zone and to recommend changes to the existing system if

necessary and the other is to conduct speed delay time survey over a stretch, study all

features of the stretch and recommend necessary changes that can be adopted to solve the

delay problem.

2.2 Spot Speed Studies

2.2.1 Existing System

As a part of establishing speed zone in a school premises, we choose a school

located at Hydernagar directly connected to NH 9. We observed that the school does not

have any speed limit or a zebra crossing, so we decided to conduct a spot speed survey

near the school premises.

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Coming to the features of the stretch, it is located on NH-9 road between

Hydernagar and Miyapur X roads. ZENAS International School is exactly located

between LISMP 3 and 1 HMR pillars.

Fig 3: ZENAS International School-aerial view

2.2.2 Disadvantages of Existing System

The school is directly connected to National Highway. Vehicles travel at very

high speed on a highway which may range from 60-80 KMPH. This is an example for

bad indication or bad signaling. There are no precautionary signs like school zone or

speed limit or zebra crossing. The high speed vehicles sometimes may not notice the road

crossing public, leading to accidents. To improvise the existing system, survey need to be

conducted

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2.2.3 Proposed System

The proposed system or mechanism will overcome the disadvantages of existing

system. Firstly various study aspects are noticed, required primary data is collected, and

the collected is analyzed. Then the experimentation is done keeping all the study aspects

in mind. The experimentation results are analyzed and an appropriate solution is

recommended to the existing system. In this case, the recommendation may be on traffic

signaling or establishing speed limits.

2.3 Speed Delay Time Survey

2.3.1 Existing System

We considered a stretch of 8.4 KM that is from JNTU to Lingampally circle. The

features of this road are

3 line road on both the sides.

Tar bitumen road.

As it is a National Highway passing through one of the major business

centers of the city, Heavy traffic is observed.

All kinds of vehicles like Buses, Cars, Bikes, Lorries, and Autos use the

road.

Six traffic signals should be crossed to reach the destination, among which

three have free left facility.

Peak hours – 08:00 AM to 10:00 AM & 05:00 PM to 08:00 PM.

Due to high traffic volume, a part of the stretch from JNTU to Nizampet faces

severe traffic jam during peak hours and Miyapur X road junction passengers faces long

stop time due insufficient roads.

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2.3.2 Disadvantages of Existing System

The three lane road is insufficient for the traffic during peak hours near JNTU,

Lingampally, Nizampet, Miyapur, and at Chandanagar. Some passengers violate the

rules; this may lead to traffic inconvenience. At some places the road is damaged and not

well maintained, this may lead to reduction in average traffic flow velocity. HMR works

are going on along the stretch length; this is causing inconvenience to the travelers. Due

to underground electricity wiring works, about 1.7mts of road width is been dug and let

open by the electricity department in the direction of JNTU to Nizampet, this is reducing

the available road width and sometimes may be dangerous during nights.

2.3.3 Proposed system

After conducting speed and delay time survey, some changes to the existing

system will be proposed after calculations and conclusions. The proposed system will

rectify the faults in present system like diverting the traffic as long as the metro work is

under progress. We will also propose changes keeping the future development of the

system in all aspects like- within a year metro transportation will be started and may

reduce the road usage to some extent. Just seeing the present situation proposing a road

extension because of a slight higher traffic volume is merely waste of funds. After

completion of metro and electricity board works, more road space will be available which

may be sufficient to manage the present traffic, so temporary recommendations will be

proposed considering the present situation.

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Chapter 3

Spot Speed Methodology

3.1 Introduction

Speed is an important measure of the quality of travel and safety of road network.

Speed by definition is the rate of movement of vehicle in distance per unit time. A typical

unit of speed is kilometers per hour (KMPH) or miles per hour (mph).

The main purpose of this study is to determine traffic parameter, specially speed. Spot

Speed measurements are most often taken at a point (or a short section) of road way

under conditions of free flow.

The intent is to determine the speeds that drivers select, unaffected by the existence of

congestion. This information is used to determine general speed trends, to help determine

reasonable speed limits, and to assess safety.

Basically, there are two types of speed: the time-mean speed and the space-mean

speed.

Space Mean Speed: It is the length of a road section divided by the average travel time

of several vehicles over this specific section.

Time Mean Speed or Spot Speed: It is the average spot speed of several vehicles

measured at a given spot.

For geometric design of roads, it is necessary to have a realistic estimate of the speeds

at which vehicles travel. Based on the speed studies, the design speed can be selected,

and other geometric elements of design such as horizontal curvature, vertical profile,

sight distances and super-elevation can be determined.

Spot Speed studies are conducted to estimate the distribution of speeds of vehicles in

a stream of traffic at a particular location on a highway.

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This is carried out by recording the speeds of a sample of vehicles at a specified

location.When we measure the traffic parameter over a short distance, we generally

measure the spot speed. A spot speed is made by measuring the individual speeds of a

sample of the vehicle passing a given spot on a street or highway. Spot speed studies are

used to determine the speed distribution of a traffic stream at a specific location. The data

gathered in spot speed studies are used to determine vehicle speed percentiles, which are

useful in making many speed-related decisions. Spot speed data have a number of safety

applications, including the following

• Speed trends,

• Traffic control planning,

• Accidental analysis,

• Geometric design,

• Research studies.

3.2 Methods of Spot Speed Measurement

Methods of conducting spot speed Studies are divided into two main categories:

Manual and Automatic. Spot speeds may be estimated by manually measuring the time it

takes a vehicle to travel between two defined points on the roadway a known distance

apart (short distance), usually less than 90m. Distance between two points is generally

depending upon the average speed of traffic stream. Following tables gives recommended

study length (in meters) for various average stream speed ranges (in KMPH)

3.2 Methods of Spot Speed Studies

Following are the some methods to measure spot speed of vehicles in a traffic stream,

in which first two are manual methods and other are automatic:

3.2.1 Stop Watch Method

In this method, markings of pavement are placed across the road at each end of

trap. Observer start and stops the watch as vehicle passes lines.

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In this method, minimum two observers required to collect the data, of which one

is standing at the starting point to start and stop the stop watch and other one is standing

at end point to give indication to stop the watch when vehicle passes the end line.

Advantage of this method is that after the initial installation no set-up time is

required, markings are easily renewed.

Disadvantages of this method are that substantial error can be introduced, and

magnitude of error may change for substitute studies. This method is only applicable for

low traffic conditions.

Fig 4: Pictorial representation of stop watch method

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3.2.2 Pneumatic Tube Method

The pressure contact strips, either pneumatic or electric, are used to indicate the

time of entering and leaving the base length.When a vehicle passes over the tube laid at

the first reference point, an air impulse is sent, which activates an electromagnetically

controlled stop-watch in the hands of the observer. When the vehicle passes over the

second tube, the stop watch automatically stops. Then the reading is noted by the

observer or is auto saved into computer.

Advantages: The risk of human error is reduced, and parallaxerror can be

avoided completely.This is the best method over short distance. It gives quite relevant

data and if it is connected through graphical recorder then it gives continuous data

automatically.

Disadvantage:Pressure contact tubes are easily sensed by the drivers which may

affect their behavior.

Fig 5: Pneumatic road tube method

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3.2.3 Doppler-Principle Meters (Radar)

This radar meters are frequently used for measurement of spot speed.It measures

speed directly by measuring the difference in the frequency between the emitted and

reflected radar waveemitted on an oncoming vehicle. It is radar meter which is targeted to

a vehicle, so the wave, the frequency between the emitted and reflected wave that the

difference is used to calculate the speed. This is normally referred as Doppler Effect.

Dynamometer actually works based on the principle of Doppler Effect, which justifies

the difference in frequency is proportional to the speed of oncoming vehicle. Using this

principle the instrument is programmed to calculate the speed of the vehicle.

This is recent advancement in speed studies; it automatically records speed, and

employs a radar transmitter-receiver unit. The apparatus transmits high frequency

electromagnetic waves as a narrow beam towards the moving vehicle, the beam changes

its frequency depending up on the vehicle’s speed and is returned to the receiver unit.

Upon calibration spot speed of the vehicle is obtained.

Though these meters are widely used by engineers, traffic polices and others these

have certain practical limitations. They are

• In some situations there is a possibility of recording wrong input like when a test

sample is obstructed by other vehicles, the triggered radar beam bounds back by

hitting the obstacle but not the test sample.

• Accurate measurements from radar meter are obtained only when the radar wave

is reflected directly along the axis of the movement. But in some cases it is

practically difficult.

Fig 6: RADAR method

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3.2.4 Electronic-Principle Detectors (Photography)

In this method a camera records the distance moved by a vehicle in a selected

short time. In this exposure of photograph should be in a constant time interval and the

distance travelled by the vehicle is measured by projecting the films during the exposure

interval. The main advantage of method is that, it gives a permanent record with 100%

sample obtained. This method is quite expensive and generally adopted in a situation

where evidence is required. Even video recorder can be used which give more accurate

result.

Fig 7: Photography method

Among these available methods, we adopted stop watch method considering the

advantages and adaptability of the method. The detailed experimental procedure followed

will be discussed in the following section.

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Chapter 4

Stop Watch Method

As this part of the project deals with establishing speed limit near a school zone,

we first calculate the spot speed of various test samples and then recommend speed limit

if required. To study the speed characteristics a stretch, it should satisfy some stretch

selection criteria. Those are mentioned below

4.1 Stretch Selection Criteria

The following are the basic features that a selected stretch should satisfy to obtain

accurate results:

Any location may be used for solution of a specific traffic engineering problem.

The geometry of road should be plain, without any adulation or slope.

For accurate results, selection a section where is road condition is good and where

drivers drive comfortably.

Intersections joining or diverting traffic should not interrupt the traffic flow or

speed of the vehicles passing the stretch.

The stretch should be free from speed breakers, precaution signs etc.., and the

drivers should be able to travel with their natural style.

Experimentation should be done in the time of free traffic flow.

Mainly the drivers should not be aware of the experiment going on, he may be

distracted.

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And the length of the section is decided using IRC guidelines

Table 1: Guidelines for selecting length of stretch

Stream Speed (KMPH) Length (meters)

Less than 40 27

40 to 65 54

Greater than 65 81

4.2 Experimentation

The equipment required to carry out stop watch method are

Stop watch

Measuring Tape

Flag

We require at least three observers to carry out the experiment. After choosing a

section that satisfies the above criteria, 30 meters stretch is measured using a

measuring tape. Two observers, one carrying stop watch and other carrying data

sheet stand at starting point of the stretch. The third observer stands at the ending

point of the stretch.

Once the observers are set in position, test samples may be selected randomly

and the observer at first point starts the stop watch immediately when the car passes

the section, and the third observer waves the flag when the test sample crosses the

last point of the section. The stop watch should be stopped immediately when the

flag is waved and the time taken by that test sample to cross the section is noted by

the second observer standing at the first point of the section. For convenience, forth

observer may assist to inform the details of the chosen test sample to the third

observer.

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Fig 8: First and Third observer recording the time of travel

Fig 9: Second observer signaling that the test vehicle crossed the section

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4.3 Data Collection

(I) Location: LISNP 3 to 1; Direction: Hydernagar to Miyapur;

Date: 26/02/2014; Time: 10:30 to 11:00 AM; Sample type: Four Wheelers

Vehicle

number

Speed(KMPH) Vehicle number Speed(KMPH)

1 45 13 48.868

2 39.560 14 50.704

3 37.240 15 47.368

4 42.187 16 49.769

5 45 17 45.188

6 36 18 46.153

7 38.989 19 52.941

8 41.538 20 56.842

9 43.724 21 49.769

10 43.027 22 38.297

11 44.444 23 45.188

12 51.674 24 46.956

Table 2: Spot speed observations(Four wheelers)

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(II) Location: LISNP 3 to 1; Direction: Hydernagar to Miyapur;

Date: 26/02/2014; Time: 11:00 to 11:30 AM; Sample type: Two Wheelers

Table 3: Spot speed observations (Two wheeler)

Vehicle number Speed(KMPH) Vehicle number Speed(KMPH)

1 46.956 13 50.467

2 40.298 14 46.956

3 40.148 15 47.161

4 48.868 16 44.628

5 54 17 46.153

6 50.704 18 44.628

7 46.956 19 36

8 52.941 20 48

9 51.923 21 38.232

10 36.610 22 48.868

11 42.023 23 40.754

12 44.628 24 46.153

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Chapter 5

Calculations and Design

5.1 Calculations

One of the greatest advantage of spot speed study is that the average spot speed of the test vehicles can be calculated both

analytically and statistically. For better understanding, we performed both the operations and they are mentioned below.

5.1.1 Analytical Calculations (Four Wheeler)

Designed speed for cars:

Sd =?

Pd = 85 %

Pmax = 91.653

Pmin = 83.323

Smin = 49 KMPH

Smax= 51 KMPH

Sd = Pp – Pmin *(Smax-Smin) +Smin

Pmax-Pmin

= 85 – 83.323 * (51-49) + 49

91.653-83.323

= 49.402 KMPH

&

Sd for (50 %)

Pd= 50%

Pmax = 62.493

Pmin = 41.66

Smin = 43 KMPH

Smax = 45 KMPH

Sd = Pp – Pmin *(Smax-Smin) +Smin

Pmax-Pmin

= 50 – 41.66 * (45-43) + 43

Designed speed at 85% and 50% are determined based on which the experiment will be concluded

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62.493-41.66

= 43.8 KMPH

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5.1.2 Statistical Calculations (Four Wheeler)

This calculation is for cross checking the values obtained in analytical analysis.

FREQUENCY DISTRIBUTION TABLE (Four wheelers)

Table 4: Frequency distribution table (Four wheelers)

Speed Range Frequency % Frequency Cumulative Frequency

36-37.9 2 8.33 8.33 38-39.9 3 12.5 20.83

40-41.9 2 8.33 29.16

42-43.9 3 12.5 41.66

44-45.9 5 20.833 62.493

46-47.9 3 12.5 74.993

48-49.9 2 8.33 83.323

50-51.9 2 8.33 91.653

52-53.9 1 4.166 95.819

54-55.9 0 0 95.819

56-57.9 1 4.166 100

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North bound Frequency curve (Four Wheelers)

Graph 1: North bound frequency curve (Four wheelers)

0

1

2

3

4

5

6

34-35.9 36-37.9 38-39.9 40-41.9 42-43.9 44-45.9 46-47.9 48-49.9 50-51.9 52-53.9 54-55.9 56-57.9

Modal speed-45KMPH

Series 1

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Frequency distribution curve (Four Wheeler)

Graph 2: Frequency distribution curve (Four wheelers)

0

5

10

15

20

25

0 10 20 30 40 50 60Speed(KMPH)

Y-Values

33

Cumulative Frequency curve (Four Wheeler)

Graph 3: Cumulative frequency curve (four wheeler)

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5.1.3 Analytical Calculations (Two Wheeler)

Designed speed for bikes:

Sd for 85%

Pd = 85 %

Pmax = 91.667

Pmin = 79.167

Smin = 49 KMPH

Smax = 51 KMPH

0

20

40

60

80

100

120

0 10 20 30 40 50 60

Y-Values

Y-Values

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Sd = Pp – Pmin *(Smax-Smin) +Smin

Pmax-Pmin

= 85 – 79.167 * (51-49) + 49

91.667-79.167

= 49.933 KMPH

&

Sd for 50 %

Pd = 50%

Pmax = 66.667

Pmin = 45.833

Smin = 45 KMPH

Smax = 47 KMPH

Sd = Pp – Pmin *(Smax-Smin) +Smin

Pmax-Pmin

= 50 – 45.833 * (47-45) + 45

66.667-45.833

= 45.4 KMPH

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5.1.4 Statistical Calculations (Two Wheeler)

FREQUENCY DISTRIBUTION TABLE (Two wheelers)

Table 5: Frequency distribution table (two wheelers)

Speed Range Frequency % Frequency Cumulative Frequency

36-37.9 4 16.6667 16.667

38-39.9 0 0 16.667

40-41.9 3 12.5 29.167

42-43.9 1 4.1666 33.333

44-45.9 3 12.5 45.833

46-47.9 5 20.8333 66.667

48-49.9 3 12.5 79.167

50-51.9 3 12.5 91.667

52-53.9 1 4.16667 95.833

54-55.9 1 4.16667 100

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North bound Frequency curve (Two Wheelers)

Graph 4: North bound frequency curve (Two wheelers)

0

1

2

3

4

5

6

36-37.9 38-39.9 40-41.9 42-43.9 44-45.9 46-47.9 48-49.9 50-51.9 52-53.9 54-55.9

Modal Speed-47KMPH

Series 1

38

Frequency distribution curve (Two Wheelers)

Graph 5: Frequency distribution curve (Two wheeler)

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Cumulative Frequency curve (Two Wheeler)

Graph 6: Cumulative frequency curve (Two wheeler)

0

5

10

15

20

25

0 10 20 30 40 50 60

Speed(KMPH)

Y-Values

40

0

20

40

60

80

100

120

0 20 40 60

Y-Values

Y-Values

41

5.2 Design of Speed Limit

Design of speed limit depends on various factors such as type of road, purpose of

road, existing average spot speed etc..,.

As we are designing speed limit for a school zone, the following guidelines are

recommended to revise while establishing a speed limit

Speed limits which apply include:

Table 6: Guidelines for establishing speed limits

Speed Limit Existing average spot speed

40 KMPH 50-70 KMPH

60 KMPH 80 KMPH

60 or 80 KMPH 90 or 100 KMPH

80 KMPH 110 KMPH

As the calculated average spot speed of the vehicles near the school is around 47

KMPH, There is a necessity to establish a precautionary board stating school zone speed

should be limit to 35 KMPH. As per norms or guidelines 40 KMPH speed limit is

sufficient, but to ensure safety the recommended limit is reduced by 5 KMPH. For

effective signing, we can mention the time to maintain the speed limit, that is, during

school hours there is no need to maintain the speed limit, and it should be followed only

during the time when the students of school are expected to use the road. Generally, it is

the time before the school starts and also during the closing hours.

42

5.3 Recommendations

1) Precaution sign stating “School Zone” should be established.

2) Speed limit board of 35 KMPH should be established along with school timings.

3) Zebra crossing for the school students should be provided.

4) School zone board should be establish before 50mts from the school

Fig 10: School zone board

35

43

Chapter 6

Speed and Delay Time Survey

6.1 Introduction

The speed and delay studies give the running, overall speeds, fluctuations in speed

and delay between two stations. They also give the information such as the amount,

location, duration frequency and causes of the delay in the traffic stream. The results of

the speed and delay studies are useful in detecting the spot of congestion, the causes

delay and in arriving at a suitable remedial measure. The studies are also useful in finding

the travel time and in benefit-cost analysis. In general the efficiency of the roadway is

judged from the travel time.

The delay or the time lost by traffic during the travel period may be either due to

fixed delays or operational delays. Fixed delay occurs primarily at intersections due to

traffic signals and level crossing. Operational delays are caused by the interference of

traffic movements, such as turning vehicles, parking and imparking vehicles, pedestrians

etc., and by internal friction in the traffic stream due to high traffic volume, insufficient

capacity and by accidents. Therefore the overall travel speed between the origin and

destination points of travel is invariably lower than the desired running speed.

There are various methods of carrying out speed and delay study, namely:

Floating car or riding check method

License plate or vehicle number method

Interview technique

Elevated observations, and

Photographic technique

44

6.2.1 Floating Car Method

In the floating car method, a test vehicle is driven over a given course of travel at

approximately the average speed of the stream, thus trying to float with the traffic stream.

A number of test runs are made along the study stretch and a group of observers the

various the details. One observer is seated in the floating car with two stop watches. One

of the stop watches is used to record the time at various control points like intersections,

bridges or any other fixed points in each trip. The other stop watch is used to find the

duration of individual delays. The time, location cause of these delays are recorded by the

second observer either or suitable tabular forms or by voice recordings equipment. The

number of vehicles overtaking the test vehicle and that overtaken by the test vehicle are

noted in each trip by a third observer. The number of vehicles travelling in the opposite

direction in each trip is noted by a fourth observer. However in mixed traffic flow, more

number of observers will be required to count the vehicles of different classes. In this

method the detailed information is obtained concerning all phases of speed and delay

including locations, durations and causes of delay.

The average journey time T (minute) in the direction of flow q is given by:

q = average volume = (na+ny)/(ta+tw)

T = average Journey time = tw-(ny/q)

Where

q = flow of vehicles (volume per minute), in one direction of the stream

na = average number of vehicles counted in the direction of the stream when the

test vehicle travels in the opposite direction

ny = the average number of vehicles overtaking the test vehicle minus the number

of vehicles overtaken when the test in the direction of q

45

tw = average journey time, in minute when the test vehicle is travelling with the

stream q

ta = average journey time, in minute when test vehicle is running against the

stream q

6.2.2 License Plate Method

In the license plate or vehicle number method, synchronized stop watches or

voice recording equipment are used. Observers are stationed at the entrance and exit of a

test section where information of travel time is required. The timings and vehicles

numbers are noted by the observers of the selected sample. From the office computations,

travel time of each vehicle could be found. But this method does not give important

details like causes of delays, delay duration and number of intersections within the test

section.

In this method observers are stationed at the ends of measuring section, about 0.5-

1.00 km long. The time and registration number of the vehicles entering and leaving the

section are noted using synchronized watches. By watching the registration numbers

later, the journey times and speed can be determined. If the traffic is too heavy to record,

some methods of sampling can be adopted. For instance, noting down only numbers

ending with an odd number will yield a 50 per cent sample. The vehicle classification can

also be noted in this method thus yielding this additional information. The accuracy that

is possible in recording time is about +0.01 minutes, which then gives an accuracy of 1 to

2 percent for journeys lasting about one minute. The watches are supported on the

recording board and are slowed to run continuously. Watches divided in to tenths and

hundredths of a minute are desirable as they facilitate subsequent analysis. Duration more

than two hours is likely to cause undue strain on the observers. Two observers are

normally employed for each direction of travel, one for nothing the registration number

and calling the same, the other for recording it along with the time. Two observers can

record at the rate of about 300 vehicles per hour

46

6.2.3 Interview Technique

In the interview technique, the work can be completed in a short time by

interviewing and collecting details from the road users on the spot. However the data

collected may not provide with all details correctly.

6.2.4 Elevated Observer Technique

Elevated observations and photographic technique are useful for studying short

test sections like intersection etc.The method is well suited to study the speeds along

different roads in an area. Since conditions may vary from section to section on the route,

the route is divided into convenient sections, say 0.75 to 1.5 km in length; it is desirable

to have the ends of these sections at major intersections so that large discontinuous speed

and flow do not occur inside the section. It is convenient to have the routes to be closed

circuits in either direction

Intersection delays studies need special attention as this is one of the major

problems of many metropolitan cities. Such studies at each intersection will help in

evaluating the efficiency and effectiveness of the control device like signal system, the

remedial measures for accidents etc.

Considering the accuracy and adaptability, we chose “Floating Car Method” to do

our speed-delay time survey. Stretch selection criteria, Detailed experimental procedure

is been discussed in the following section.

47

Chapter 7

Floating Car Methodology

7.1 Stretch Selection Criteria

For study purposes select a stretch which has more number of intersections and

with heavy traffic. In the case of practical problem solving select a stretch which has or

covers all the characteristics of whole area of experimentation. Following points need to

be kept in mind while selecting a stretch for speed delay time survey

The selected stretch should showcase all the characteristics of the area in which

you are supposed to survey.

The observer should be able to calculate the traffic volume coming in opposite

direction.

The stretch should at least support constant 40 KMPH speed.

7.2 Experimentation

A Small, preferable even, number of testing car is required-usually two-each car

carrying a driver and three observers. One observer in the car counts opposing traffic,

using hand tallies. Another observer carries a recording board on which a watch is

mounted.

The recording board carries a journey log prepared in advance, on which the

observer records the totals from the hand tallies and times at predetermined point’s en-

48

route, together with the times of stopping and starting at intersections. It is desirable to

have two stop watches, one for recording the continuous time at different points en-route,

and the other for measuring the individual stopped time delays. The second watch can

accumulate the delay time as the observer operates buttons. A third observer records the

number of overtaking and overtaken vehicles, and if required, the number of parked

vehicles. If only two observers are available, the driver is instructed to overtaken as many

vehicles as do overtaken him and no record need be kept of those vehicles.

It is desirable that twelve to sixteen runs in each direction along the route be made

and the results averaged out so as to arrive at an accurate estimate of the speed and flow.

Advantages:

(i) The method gives an unbiased estimate of the flow. Random errors can,

however, occur due to observers’ errors and random fluctuations in flow, but these are

not serious under normal conditions.

(ii) As compared to the stationary observer method, the moving observer method

is equivalent to a stationary count over twice the single journey time. Hence it is

economical in manpower.

(iii) It enables data on speed and flow to be collected at the same time. This is

particularly advantageous when analyzing the relations between the two.

(iv) It gives mean values of flow and speed over a reaction, rather than at a point.

Thus it gives directly the space mean speed, whereas spot speed studies gives the time

mean speed.

(v) It gives additional information on stops at intersections, delays, parked

vehicles etc.

49

Fig 11: Map showing starting and destination points-speed delay time survey

7.3 Data Collection

Table 7: Speed delay time survey observation table

50

Direction Journey time

(min:sec)

Stopped delay

(min:sec)

Number of Vehicles

Overtaking Overtaken Opposite direction

JNTU to Lingampally

Trip 1 20:42 05:30 230 102 3739

Trip 2 18:37 03:31 97 32 3072

Total 39:19 09:01 327 134 6811

Average 19:40 04:30 163.5 67 3405.5

Lingampally to JNTU

Trip 1 20:47 06:40 203 111 3524

Trip 2 17:36 03:13 104 49 2547

Total 38:23 09:53 307 160 6071

Average 19:12 04:56 153.5 80 3035.5

51

Calculations (Speed delay time survey):

i) JNTU – Lingampally

na = 3405.5 vehicles

ny = 163.5 – 67 = 96.5

tw= (average journey time from JTNU to Lingampally)

= 19.66 minutes

ta = (average journey time from Lingampally to JNTU)

=19.20 minutes

Therefore,

q = average volume = (na+ny)/(ta+tw)

=(3405.5+96.5)/(19.66+19.20)

= 90.11 vehicles/minutes

t’ = avg. Journey time = tw-(ny/q)

= 19.66-(96.5/90.11)

= 18.45 minutes

Chapter 8: Calculations on Speed Delay Time Survey

52

ii) Lingampally – JNTU

na = 3035.5 vehicles

ny = 73.5

tw = (avg journey time from JTNU to Lingampally)

=19.66 minutes

ta = (avg journey time from Lingampally to JNTU)

=19.20 minutes

Therefore,

q = average volume = (na+ny)/(ta+tw)

= (3035.5+73.5)/(19.66+19.20)

= 80 vehicles/minutes

t’ = avg. Journey time = tw-(ny/q)

=19.2-(73.5/80)

=18.28 minutes

53

54

Chapter 9

Discussion and Conclusions

Problems and Solutions

1. Conjunction at Bus Bays: Near Nizampet bus stop, the buses are halted on the road

creating a problem to other vehicles passing the intersection.

Solution: While going from JNTU to Lingampally at Nizampet the buses halt on the road

due to lack of bus bay space so a bus bay can be provide after the signal.

The Bus driver should be instructed to not to stop the buses on the road and awareness

may be created among the public not to wait on the road for buses and to use bus bay.

The bus bay near more (Nizampet) is presently not in use. The bus bay must be

renovated by laying a new road so it can be effectively used.

2. Uneven pavements at Hydernagar and Miyapur metro: the damaged roads near

hydernagar and miyapur are causing volunteer slowdown of vehicles and inconvenience.

Solution: New roads of high quality assuring more life time should be laid as it is a

national highway

3. Spots of Congestion: JNTU to Nizampet the place preoccupied by metro has not been

finished even though the traffic is allowed the road work is not finished due to this

unevenness the vehicles are not in a position to use the complete space available.

4. Intersection of traffic flow: Near Hydernagar junction huge volume of traffic is using U

turn or Right turn and in the process majority of road is blocked on either sides.

It is recommended to provide a signal and a free left so that the traffic flow in opposite

direction is not obstructed.

55

References

Section 166 of the Transport Operations (Road Use Management) Act 1995

S K Khanna (2010), Traffic Engineering, Highway Engineering, Nem Chand & Bros.

Robertson, Douglas H., Et. Al., Spot Speed Studies, CH.3 of Manual of Transportation

Engineering Studies, Institute of Transportation Engineers, 1994, pp 33-51

AASHTO. 2001. A Policy on Geometric Design of Highways and Streets (Green Book).

4th ed. Washington, D.C.: American Association of State Highway and Transportation

Officials.

Indian Road Congress, Recommendations regarding Alignment, survey and Geometric

designs, IRC: 52-1981.

Drew, D.R., Traffic flow theory and control, McGraw-Hill Book Co., New York.

Kennedy, N., Kell, J. H. and Homburger W. S., Fundamentals of Traffic Engineering,

Institute of Transportation and Traffic Engg., University of California.

Capelle, D. G., Clevelend, D. E. and Rankin, W. W. An Introduction to Highway

Transportation Engineering, Institute of Traffic Engineers, USB.