TRAFFIC VOLUME STUDY

CE : 452

Course Name : Transportation

Engineering Lab-IICourse Teachers : Minhajul Islam Khan,

Nuzhat Azra

Welcome To The Presentation On

Group Members

Group 5

TANJIN MUNIRA KHAN 11.01.03.081

MD. NAZMUL HUDA 11.01.03.084

SHAMS TANVINA 11.01.03.089

TAHMINA FERDOUS 11.01.03.111

NURUN NAHAR HIMIKA 11.01.03.117

SAMARA ZERIN 11.01.03.121

TAREQ HASAN 11.01.03.127

S.M.MAROOF HASAN NAHIN 10.02.03.093

Theoretical Studies

What is traffic volume studies:

Traffic volume study means determining the number, movement and

Classification of Roadway vehicle at a given location or point of traffic

stream. So it is defined as the procedure to determine mainly volume of traffic

moving on the roads at a particular section during a particular time.

Scope of Traffic Volume Study:

Scope of traffic study

General information for

road conditions, users & surrounding

areas

Keeping record of pavement

performance & Maintenance.

A ranking system to prioritize

maintenance needs

A summary of the overall condition of the pavements in any area of the

road section.

Helpful for special design, use of materials or construction

projects.

A uniform rating system for each

side.

Objectives of Traffic Volume Study:

1.General Objectives :

Geometric Design

Roadway traffic Design

Planning Purpose

Improvement Purpose

Dynamic traffic management purpose

2. Specific Objective:

Determination of vehicle composition in traffic stream.

To determine service flow rate in PCU/PCE unit.

Estimation of Average daily traffic (ADT) using expansion factors.

To determine directional distribution (DD).

To illustrate flow fluctuation curves.

Some keywords related to the study:

Volume, Demand, Capacity, Rate of Flow, Average Daily Traffic (ADT),Average Annual

Daily Traffic (AADT),Average Weekly Traffic (AWT),Annual Weekday Traffic

(AAWT),Expansion Factor, Peak hour factor ,PHF = hourly volume/maximum rate of flow,

Design Hourly Volume, Interrupted flow: ,Uninterrupted flow, Saturation flow, Service flow

rate, Free flow, Forced flow, Stable/ Steady flow, Unstable flow, Peak flow, Off-peak flow,

Tidal flow, Contra flow, VMT (Vehicle Miles Traveled) or VKT (Vehicle Kilometers

Traveled),PCU/PCE

Relative formulas used for the study:

Methods of traffic volume study:

Equipments Used For Automatic Counting Method:

1.Pnematic Tubes 2. Weigh-In-Motion Sensor Types

3. Vehicles counting by video camera (a) 3. Vehicles counting by video camera (b)

4. Typical layout of traffic loops on the road surface 5. Traffic counters

6. Bending plate and pneumatic road tube 7. Automatic traffic recorders

9. Automatic counting station secured and 10. A speed, axle and traffic flow data collection

station with a lockable counting equipment box.

operated by solar power

Equipments Used For Manual Counting Method:

1.Mechanical counting boards

2. Electrical counting board: 3.Vehicle counting software

Factors affecting vehicle counting:

Weather conditions.

Purpose of the traffic counting.

Method of traffic counting.

Location of the counting sites.

Traffic flow level.

Road type.

Traffic composition.

Practical studies: Data collection procedure:

Location Selection

Distribution of the Work

Preparations For Collecting

Data

Reconnaissance survey

Survey design Trial Survey Problem Identification

Adjustment into Survey Design Final Survey

Location and data collection method:

Location : Panthpath to Russel Square

Method: Manual data collection method was used.

Result of group 5: (at a glance)Traffic Volume Study

Station Name: Near Russel Square Intersection

Direction: West to East Time: 9am-10am

Surveyors group: Group 5 Weather condition: Hot, Sunny humid day

Date: 16th November 2014 Day: Thursday

Fig: Vehicle counting

VEHICLE CLASSIFICATION OBSERVATION IN 30 MIN

Bus 4

CNG 159

Car 254

Jeep, Microbus, Ambulance 246

Motorcycle 114

NMV 220

Utility 22

Truck 0

Fig: Vehicle comparison in pie chart

16% 0%

25%

24%

0%

22%

2%11%

Number of VehiclesCNG

Bus

Car

Jeep,Microbus,AmbulanceTruck

Types of Vehicle PCU factor PCU factor (Total

Vehicle in 30 min)

Flow(PCU) in 30

min (Actual value)

Service flow factor(PCU in

1 hr)

Bus 3 4 12 24

CNG 0.5 159 79.3 159

Car 1 254 254 508

Jeep, Microbus, Ambulance 1.5 246 369 738

Motorcycle 0.25 114 28.5 57

NMV 0.5

220

110 220

Utility 1.5 22 33 66

Truck 0 0 0

Service Flow rate 1772 PCU/hr

Fig. Service Flow Rate Calculation

HEF

Value Time

18.80 9:00 am - 10:00 am

17.11 10:00 am - 11:00 am

18.52 11:00am – 12:00 pm

Estimation of Average Daily Traffic (ADT):From Survey data,

Group 1: 1263 PCU/hr

Group 2: 1480 PCU/hr

Group 3 : 1455 PCU/hr

Group 4: 1772 PCU/hr

Group 5: 1533 PCU/hr

Group 6 : 1722 PCU/hr

Estimated 24-hours volume for Thursday using HEF (Hourly expansion factor) = (1772*18.80+1533*17.11+1722*18.52)/3

= 30478.22

From 24- hours volume for Thursday estimated volume for the work using DEF* (Daily expansion factor) total 7 days volume

= 30478.22*7.012

= 213713.278

So,

ADT ( 24 hours volume) West to East direction= 213713.278/7

= 30530.47 PCU = 30531 PCU (Rounded)

Table: 5.4 Hourly Expansion Factor

*DEF = 7.012 for Thursday.

Directional Distribution

46%

54%

Directional Distribution

E to W

w TO E

6.1Estimation of % ADT at Each direction:

East To West ( Panthapoth to Russel Square)

Table 5.6.1

Group

No

Location

Time

Service flow

rate

(PCU/hr)

ADT

(PCU)

% ADT

1

Near Panthapath

Intersection

9:00 am -

10:00 am

1263

25532

4.955

2

Near Health and Hope

Hospital

10:00 am -

11:00 am

1480 5.797

3

Near Russel Square

Intersection

11:00am –

12:00 pm

1455 5.699

From

Group No 1. 1263 PCU/hr

Group No 2. 1480 PCU/hr

Group No 3. 1455 PCU/hr

West To East (Russel Square to Panthapoth)

Table 5.6.2

Group No

Location

Time

Service flow

rate

(PCU/hr)

ADT

(PCU)

% ADT

4

Near Russel Square

Intersection

11:00am –

12:00 pm

1772

30531

5.804

5

Near Health and Hope

Hospital

10:00 am -

11:00 am

1533 5.021

Limitations:

This volume study was practiced by un-skilled enumerators, which may lead to some error in data

collection process.

Data were collected for 30 minutes by each group, although it is assumed that the data collected for three

hours actually it is counted for only one hour which may not represent the hourly fluctuation of traffic.

AADT was calculated using expansion factors. These expansion factors established based on data collected

in a rural road of Sweden, the actual daily expansion factors will be much different from what is used. So

they will not give actual ADT.

Data collected by manual method of counting, which is unreliable and irreversible

Recommendation:

Trained and skilled enumerators should collect data which is first requirement of Manual counting

Automatic counting system should be introduced for more reliable data.

Actual expansion factor should be introduced for Dhaka city

For design purpose minimum 3 days Data should be collect.

Before final survey reconnaissance survey or pilot survey is necessary.

Special Observation:

All the procedure, methods, equipments were

recommendation from AASHTO(American Association

of State Highway and Transportation Officials). As the

roadway condition, vehicle types, users, surrounding

areas, weather all the things are different from the

AASHTO code, so we should develop our own code or

follow the neighboring country’s code.

THANK YOU