SCIENCE AND TECHNOLOGY
This Presentation is done as a requirement of a Sessional
ENGINEERING SESSIONAL II
To engineer transport mode or traffic system the most important factors are-
1.The available traffic volume and its capacity,
2.The necessary speed of vehicles to provide continuous
3.The different parameters that controls and effects
So basic study area should be comprised of as follows :-
In this case, our study subject is ----------
This will be presented by-
Bakhtiar Omar Omi
Md. Firoz Mahmood Ovi
Let’s have a background check on the condition of vehicles in Capital of Bangladesh
Dhaka City--General Information
815.85 sq. km (approx)
7 million (approx.)
Summer: max 36.7°C & min 21.1°c
Winter : max 31.7°C & min 10.5°c
2540 mm annually.
80 percent (approx.)
Transport Sectors &Vehicle distribution of Dhaka City is as follows-
Income-wise use of different Transports
Car, Taxi Service, Micro Bus
and other private vehicles.
Medium Income Rickshaw, Auto Rickshaw,
Bicycle, Motor Cycle,
Carriage, Car, Bus, Minibus
Bus and Tempo
Pick up, Van, Human Driven
Distribution in Dhaka City
To determine of vehicle composition in traffic stream.
To determine of service flow rate in PCU/PCE unit.
To estimate of ADT based on expansion factors.
To determine directional distribution(DD).
To draw flow fluctuation curves.
Scope of The
Magnitudes, classifications and the time and directional split of
Proportions of vehicles in traffic stream;
Hourly, daily, yearly and seasonal variation of vehicular flows;
Flow fluctuation on different approaches at a junction or different
parts of a road network system.
To define Traffic Volume study various parameters need to be introducedTotal number of vehicles that pass over a given point or section of a lane or roadway during a
given time interval
•The equivalent hourly rate at which vehicles passing over
Rate of Flow
•Time interval less than 1hr. Usually 15 min
Service Flow Rate
•The maximum hourly rate of a roadway section
•Time interval any given period under prevailing roadway condition
Average Daily traffic (ADT)
Represent a 24-hour count at any specified location
Annual Average Daily Traffic (AADT)
Represent the average 24-hour traffic volume at a given location averaged over a full 365-day
There are 3 expansion factors. They areExpansion Factors
Hourly Expansion Factors (HEF ) ;
Daily Expansion Factors (DEF ) ;
Monthly Expansion Factors (MEF ).
Capacity is defined as the maximum number of vehicles, passengers, or the
like, per unit time, which can be accommodated under given conditions with a
reasonable expectation of occurrence.
Capacity is independent of the demand. It speaks about the physical
amount of vehicles and passengers a road can afford.
Level Of Service:
A term closely related to capacity and often confused with it is service
volume. When capacity gives a quantitative measure of trac, level of service or LOS
tries to give a qualitative measure. A service volume is the maximum number of
vehicles, passengers, or the like, which can be accommodated by a given facility or
system under given conditions at a given level of service.
Study Zone : Tejgaon; Industrial Area
Population : 2,20,012
Area : 8.75 km²
Study Road : SHAHEED TAJUDDIN AHMED AVENUE
Length : 0.560 km
Lanes : 3 lanes both direction; each 13 ft approximately
Width : 42 ft at intersection of SAATH RASTA
44 ft at intersection of FLYOVER
Before proceed to vehicle counting it is customary to do• Pilot Survey,
From our Reconnaissance Surveys we found that• At Saath Rasta intersection there was a construction going on for a fly over .
• Most of the buildings are there educational & official.
• Around the metal sculpture there are about 7 manholes & about 15 potholes.
• At median there are 6 median openings including both ends.
• At footpath there is more than enough manholes.
• Along flyover to saath rasta ther is 5 and along saath rasta to flyover there is 4 local roads.
• Along saath rasta to flyover there is 2 gas station and 1 filing station
• On street parking is common in both direction.
•At Saath Rasta vehicles are actuated manually by TRAFFIC POLICE.
• Although a signal actuated intersection, Fly Over intersection is manually controlled.
Conditions & Specifications
Location: Shatrasta to flyover
Station: In front of BG Press
Date: 20th June 2013(Thursday)
Time: Time of data collection 8:30 am to 8:45 am
Weather Condition: Sunny
Observation: Classified Vehicle Counts
Method: Direct Manual Method
Duration: 15 minutes(Short Count)
Equipment: Stop watch, Pencils, Eraser, Tally sheet(Field Data Sheet), Clip board
Number of Enumerators: Five
• Before the day of counting we had gone to our location for
a reconnaissance survey and locate necessary reference
• On the promised day, we reached our station and observed
the various vehicles that went by and distributed specified
vehicles among our 5 Enumerators to count them for 15
• We use tally to lessens our clumsiness and error of
• After 15 minutes we counted the total vehicles of each
• Finally we prepared a field observation data sheet and filled
the necessary data.
Problems in counting
Position of Enumerators
Saatrasta To Flyover
Problems in counting(Continued)
Position of Enumerators
Saatrasta To Flyover
Steps of Data Collection & Synchronization:
Step 1 : Count the vehicle by means of manual method in this tally sheet method.
Step 2 : Collect & Divide it in various types of vehicles.
Step 3 : Record values obtained in field survey book or any notebook.
Step 4 : Calculate different parameters that is related to volume studies.
Step 5 : Input the collected or calculated values according to suitable time
Step 6 : Check if necessary requirements are fulfilled by data archive & results.
SRF=Total Counted Vehicle Manually or Automatically in an
TV=Total Converted Vehicles or PCU*4
Percentage of any value =
Arbitrary Specifications And Abbreviations:
F-S = Flyover to Saath Rasta.
S-F = Saath Rasta to Fly Over.
PCE = Passenger Car Equivalent : A Passenger Car Equivalent is essentially the impact that a mode of
transport has on traffic variables (such as headway, speed, density) compared to a single car.
PCU = Passenger Car Unit.
Used Time Intervals for Flow
SFR = Service Flow Rate.
TV = Total Volume.
TDV = Total 24 Hour or Daily Volume. 8:15-8:30AM
TWV = Total 7-Days or Weekly Volume.
ADT = Average Daily Volume.
AADT = Annual Average Daily Volume
DD = Directional Distribution.
TAF = Total Annual Flow.
SD = Standard Deviation.
VPH = Vehicle Per Hour or veh/hr.
VPD = Vehicle Per Day or veh/day.
RHD = Roads and Highway Department.
AASHTO = American Association of State Highway And Transportation Officials.
TYPE I = Car, Jeep, Micro, Taxi.
TYPE II = 3-wheeler.
TYPE III = Bus.
TYPE IV = Motorcycle.
TYPE V = NMT = Non-Mechanized Transport.
TYPE VI = Utility & others
Data Synchronization for Flow Fluctuation
For Traffic Along Fly Over to Sath Rasta
TCV for Type I vehicle is 262 whose PCE=1
PCU = 262*1 = 262
TCV = 511; So, SFR = TCV*4 = 2044.
PCU = 475; So, TV = PCU*4 = 1900.
TDV = TV*HEF =1900* 17.11= 32509.
TWV = TDV*DEF = 32509*7.012 = 227953.
ADT = TWV/7 = 227953/7 = 325695.
AADT = ADT*1.395 = 25695*1.395 = 45427.8.
For Total Vehicular Split
% By 137787 % By SFR
Along F-SDirection total ADT = TV
Along S-F Direction total45 = 168274 44
% ADT along F-S = 137787/(137787+168274) = 45%
% ADT along S-F = 168274/(137787+168274) = 55%
% By ADT
For Individual Vehicular Split
Total Vehicular Distribution On the Study Location
Sum of Counted
Flow Fluctuation for Individual Vehicular Split
Result Analysis & Discussion
• Result is the most critical part in a survey or
project or data-based research.
• Result decides or gives an overview on
whether the value we have got or collected is
good or insufficient to go further in our
Result Analysis & Discussion(continued)
Comparison of Service Flow Rate (SFR)
Along Flyover - Shatrasta
For 1hr & 15 min.
Along Shatrasta - Flyover
For 1hr & 15 min.
Reason for increasing SFR along Shatrasta to Flyover
• Farmgate to Nabisco
• Follows one way route
Reason for increasing SFR along Shatrasta to
Comparison of ADT & % of Vehicle along S-F & F-S
•In the pie charts of %DD it is
seen that direction S-F has the
•In the pie charts for vehicle
composition it is seen that there is
always greater percentage of
private transport(Car, Jeep or
micro) than public transport(bus).
Comparison of Total ADT of assumed 1hr
Conclusion & Recommendation
SFR may be increased by
• Lane width
• Lateral clearances
• Free-flow speed
• Smoother terrain
• Selection of geometric design
for an intersection
Performing diverging &
lane for NMT
Conclusion & Recommendation(continued)
Traffic volume counting
should be automatic and most
method as it is not clumsy.
Before final survey
reconnaissance survey or pilot
survey is necessary.
Choose a vintage point; if not
possible then select a
In case of manual counting
try to keep a hand counting
Wear retro-refractive dresses.