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8/11/2019 Highway Engineering Lecturer Notes Chapter 1 2
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HIGHWAY ENGINEERING
ECG 304
Intan Shafika Saiful Bahri
Faculty of Civil Engineering
UiTMPP
1
2
3
4
5
6
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Course Outcomes
1. Describe the process involved in the development andconstruction of highways
2. Carry out simple traffic studies and apply the
knowledge in highway geometric design and traffic
control devices by using recommended standards andspecification
3. Perform simple flexible pavement design according to
JKR Arahan Teknik (Jalan) method and the selection
of appropriate material for used in the construction.4. Supervise road construction, identify road defect and
recommends appropriate solution.
5. Perform the standard highway laboratory tests and
data analysis.
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Programme Outcomes
1. Ability to acquire & apply basic knowledge of science,mathematics & engineering.
2. Ability to communicate effectively, not only with engineersbut also with the public.
3. Ability to identify, formulate & solve engineering problems.4. Ability to function on multi-disciplinary teams.
5. Ability to act effectively as an individual and in a group,with leadership, managerial & entrepreneurial capabilities
6. Understanding the social, cultural, global & environmental
responsibilities & ethics of an engineering personnel & theneed for sustainable development
7. Recognizing the need to undertake lifelong learning &possessing the capacity to do so.
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Course Description
Historical development of highways in
Malaysia
Traffic Engineering theory Road geometric design
Traffic control devices
Pavement design
Road construction and maintenance
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Chapter 1
Content:
1. Development of highway
transportation
2. Highway classification and
administration
3. Feasibility studies and route location
4. Road safety and current issues
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Learning Outcomes
At the end of this chapter, students should be able to:
Describe the process involved in thedevelopment and construction of roads andhighway as general as well as in Malaysia.
Describe the general aspects of highwayclassification and administration
Explain the importance of feasibility studies andidentify the route location consideration factors.
Discuss on way to improve road safety andcurrent issues (transportation challenges).
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Development of
highway transportation
Transportation :Everything involved in moving either theperson or goods from the origin to thedestination.
Transportation
Mobility
Accessibility
Movementsdifferent modes
e.g walking, driving etc
Entry and exit
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Why do we provide and develop roadinfrastructure?
To expedite economy recoverydevelopment
May benefit the surrounding areas -upgraded to reduce accidents, congestions
Investment in mode and roadinfrastructure to meet the demands and
private transportation
Development of highway transportation (cont)
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History of road construction
Roman Roads
Metcalfs Road (1717)
Telfords Road (1757)
Mac dams Road (1756)
Development of highway transportation (cont)
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Roman Roads
Paving Stones
Fine Concrete
Broken Stones
Rubble Stones
Used by horses,chariot, wagon
pulled byanimals
Made-up fromthe stone blocksplaced closedtogether
Development of highway transportation (cont)
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Metcalfs Road
Gravel
Excavated Road
Material
Large StoneFoundation
Insisted on gooddrainage andfoundation orsubbase
carriageway wasarchedassistsurface waterdrainage
Crossing soft ground,he introduced asubbase raft ofbundled heather
Development of highway transportation (cont)
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Telfords Road
Gravel
Broken Stone
Hand Pitched
Stone
Improved ride ability- sandwich smaller
stones between the
boulders smaller stones filled
voids between the
stone blocks
compacted until
smooth surface
obtained
Development of highway transportation (cont)
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Mac dams Road
Camber
Gravel
Several layers of compacted stones Foundation improvementremoving the
topsoil
Development of highway transportation (cont)
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Last decade beforeindependent tar roadconstructed in cities
and town Mac Adam
Animal drawn carts to
mechanical andmotorized vehicles
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Pre-Independent Era
Before independent walking or animalscart and few motorized car by means of
footpath and bullock cart tracks Rubber plantation and tin mining increasedemand for a better serviceability of roadnetwork weak laterite
Planning of road in Malaya BritishAdministration
Development of highway transportation (cont)
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Now, Malaysia has one of the finest systemsof road network system in the world
Bituminous or concrete road provideaccessibility to residents (urban or rural) Expressway stretching from the north to the
south of peninsular Malaysia (PLUS) Federal highway links between states
Post-Independent Era
Development of highway transportation (cont)
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Post-Independent Era
http://upload.wikimedia.org/wikipedia/commons/c/ca/NorthSouth-Expressway.jpghttp://en.wikipedia.org/wiki/Image:FederalHighwayKL.JPG8/11/2019 Highway Engineering Lecturer Notes Chapter 1 2
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Highway/Road Classification
Roads are divided into two groups by area: -
Rural Urban
*Located outside
of cities
* Serve as links
between population centers
*Used for commuting
shopping trips
* Serve areas of
high density land
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Rural Road
Expressway
- divided highway for through traffic
- full access control and grade separation at all
intersection.
- speed limit is 110 km/h
Highway
- link up directly/indirectly federal capitals, state capitals.
- serve long to intermediate trip lengths
- speed high to medium (not important as expressway)
- smooth traffic with partial access control
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Primary road
- major roads within a state
- serve intermediate trip lengths medium travelling speed
- smooth traffic with partial access control
- link up state capitals, district capitals and major towns
Secondary road
- major road within district
- serve intermediate trip lengths with partial access control
Minor road
- apply to all road other than mentioned earlier
- serve mainly local traffic, short trip lengths, no access
control
Rural road (cont)
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Urban Road
Expressway
- as mentioned in rural road
Arterial
- continuous road with partial access for through
traffic within urban area
- Convey traffic from residential area to CBD
- smooth traffic flows and carry large trafficvolume
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Collector
- Serve as collector or distributor between the
arterial and local road system
- partial access control
- penetrate and serve identifiable neighbourhoods,
commercial areas and industrial areas
Local street
- basic road networks within a neighbourhoods
- serve direct access to abutting land
- links to the collector road short trip lengths
- through traffic should be discouraged
Rural road (cont)
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Highway Administration
Federal State
City Hall, Municipal orLocal Council
Kampung (District Office)
Roads
depend on
jurisdiction
Under Federal Road Ordinance
Linking State Capitals, airport,
railway station and ports
Road within the FELDA land
scheme those with other regional
land scheme constructed with
Federal funds
Constructed with state
funds
Local Authority
Private
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Traffic census
Class of Road
Capacity
RouteLocation
EnvironmentalImpact
Assessment
Feasibility
Study
Structures
Finalizing the
Route
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Route location
Consideration Factors:
Topography terrain
Soil condition Environment
Economy/socioeconomic
Politic History
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Example:
7- Keep grades and
curvature to minimum
6- Avoid sudden changes in
sight distance, especially
near junction
1- Avoid crossing
waterways2- Flat area rather
than mountainous
3- Avoid
destruction/removal
man-made culture
4- Avoid deep cuttings and
expensive tunnel
5- Locate near to sources
of pavement material
8- Avoid ground of
mining subsidence
9- Locate highway on soil
that need least pavement
thickness above it
10- River crossing should be right
angle
Route location (cont)
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Road Safety in Malaysia
How to improve?
Multimedia RoadSafety Campaign
Ops STATIK and Ops SIKAP
Intro to Defensive DrivingProposedAmendments ToRoad Safety Act
1987
Increase awareness and
understanding of road
safety
Improve heavier
penalties on drivers
including mandatory jail
Drivers offences
recorded and
summonses were given
Upgrading quality of
instruction, instructors
and training facilities at
driving school
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Safety helmet &safety clothing
Proposal forDedicated
Motorcycle Lane
Proposal to Limit
Max Speeds ofMotorcyclists
Road Safety in Malaysia (cont)
How to improve?
Safety campaigns
at state district
level
To reduce
accidents and
fatalities
Still under study
by The Ministry of
Transport
Be a policy
decision for
proposed new
highway
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Standard application to
Malaysian Roads
Higher design speeds for roads those
provide long distance travel
Lower design speeds for roads those
serve local traffic, where the effect of
speed is less significant
Higher standard for roads with heavier
traffic
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In Malaysia, design standards for roads areclassified into 7 groups for urban & rural
categories. The reason why road designstandards in Malaysia need to be standardizedparticularly with their geometric design featuresare as follows:
To provide a uniformity in the design ofroads based on the performance requirements
To provide consistent, safe and reliable road
facilities for traffic movementTo provide a guide for less subjectivedecisions on road design
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Agencies Involved In Highway &
Traffic JKR (The Pub l ic Work s Department)
- Implementation of development projects(federal road, state road, bridge & airport)
- make sure all roads are in a good condition & safety
JPJ (The Road Transport Department)- increase road safety through observation ofmotorized vehicles & drivers
- implement the Road Transport Act 1987
- Update the road tax system
LLM (Malaysia Highway Authori ty )
- plan, design, construct & maintain highway links &facilities.
- collect the toll & other payment which are related.
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Benefits of Highway Privatization
Reduce government financial burden
Cost saving due innovation in const.techniques
Users enjoy improved standard ofservice & greater accessibility
Earlier implementation and completionof highway project
Create more job opportunity
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Roadway Ideal Conditions
Lane width 3.6 m
Clearance 1.8 m
Free-flow speed of 100 km/h
No No Pass ing Zone on two-lane highway
No parking near the curb
Level terrain
No pedestrians
Only passenger cars in the traffic stream (no
heavy vehicles)
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TransportationSystem Challenges
Transportation system exists to meetperceived socialandeconomic needs.
As the transportation system itself evolves, situationsarise as a problemserve as challenges to thetransportation engineering profession.
These challenges are
1. Managing congestionby demand or supply measures
2. Improving safetytraffic accidents concern
3. Providing equal accesspoor, elderly, and physically
handicapped4. Protecting the environmentEIA
5. Incorporating new technology - ITS
6. Securing financial resources - funding
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Current Issue
Serious urban traffic congestion Highway-related crashes
- Over 40,000 traffic fatalities each year Delay Parking difficulties
Pollutionnoise and air (CO,NO, hydrocarbons)
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Chapter 2
Content:
1. Spot speed studies, design speed,
operating speed, running speed and
speed limit
2. Traffic volume characteristics, flow
rate, highway capacity and Level of
service (LOS)
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Learning Outcomes
At the end of the chapter, students should be able to:
1. Carry out simple speed studies and apply the
knowledge in highway geometric design by usingrecommended standards and specification.
2. Carry out simple volume studies and apply theknowledge in traffic signal design by using
recommended standards and specification.
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Contents
Traffic Stream ParametersMicroscopic
Macroscopic
MeasurementsManual
Inductive loops
Speed guns
Traffic Stream ModelsGreen shield's speed-density relationship
Fundamental diagram
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Traffic Studies
Three (3) main categories:-
1. Inventories
A list or graphic display of existing information
street widths, parking spaces, transit routes, etc2. Administrative
Existing engineering records, available in
government agencies & departments
3. Dynamic
collection of data under operational conditions
speed, traffic volume, travel time & delay,
parking and crashes.
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Traffic
measurements
Plan, improve road system
Distribution & performance of existing
traffic
Traffic flow & speed
Traffic planning studies
Implemented with the help of 3-Es(Engineering, Enforcement and Education)
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Microscopic vs. Macroscopic Measures
Microscopic measures: individual vehicle
1. Time headway: hi (sec/veh)
2. Space headway: si (ft/veh or km/veh)
3. Speed of individual vehicle: ui (mi/hr or km/hr) Macroscopic measures: average of n vehicles
1. Flow: q (veh/hr or vph)
2. Density: k (veh/mi or veh/km)3. Speed: u (mi/hr or km/hr)
q = uk
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Spot Speed Studies
Study of speed of traffic atone point or spot on atraffic way
Aimsto determine theenforceable speed limits
To estimate the speeddistribution of the trafficstream
110
km/j 80
km/j90
km/j30
km/j
60
km/j
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Time of day & Duration
1. Establish posted speed limits2. Observe speed trends
3. Collect basic data
4. Response to citizen complaints
reflects the nature of complaints
Duration at least 1 hour and the sample sizeis at least 30 vehicles.
Traffic is
free-flowing,
usually off-
peak hours
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Where to make spot speed studies?
Free flow
Junction
High frequency of accident rateImportant locations for traffic operation
Representative location for basic data survey
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Factors affecting spot speed studies
Driver
Vehicle
Roadway
Traffic
Environment
OROR
OR
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Application of spot speed data
For trends in the
operating speed
For speed at
problem location
For traffic
operationspeed
limit & safe speedat curve
For geometric
design features
For research
studies
110
km/j
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Methods of Measurement
Manually Automatically
200m
0 sec
Speed = distance/time
= 200m/8sec
V = 25m/s = 90kph
8 sec
Speed Studies
-Road detectors
-Radar speed meter
(commonly used)
Or Sonic detector
-Time laps camera
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Manual
Observe the time required by a vehicle to
cover short distance.
Direct timing procedure
Two reference points are located at aroadway, fixed distance apart.
Observer starts and stops a stopwatch as
a vehicle enters & leaves the test section.
It is most uncomplicated way.
Disadvantages: Parallax effect
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Road detectors
Classified into two general categories:
a) Pneumatic road tubes two tubes laid across the lane
an impulse is recorded when the frontwheels pass over the first tube, secondimpulse is recorded when the front wheelspass over the second tube.
time elapsed between the two impulses &
distance between the tubes are used tocompute the speed.
b) An inductive loop rectangular wire loop buried under the roadway
surface.
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Advantages:
a) human errors are reducedb) accurate results
Disadvantages:a) devices rather expensive
b) affect driver behavior
c) wear & tear
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Speed Meter
Two types:
a) Radar speed metertransmit signal onto a moving vehicle
change in frequency between transmitted signal
& reflected signal = speed.
operating distance about 45 m
b) Sonic detector meterusing ultrasonic tone (18-20 kHz)
output in current voltage that is proportional to
vehicle speed.
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Advantages:
a) portableb) reduced the influence on driver
behaviour.
Disadvantages:
a) difficult for two-lane road
b) expensive
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SpeedRate of movement of the vehicle, expressed in
miles/hour (mi/h) or kilometers/hour (km/h).
Average spot speed /Arithmetic mean speed /
Time mean speed (*)
- Arithmetic mean of all observed vehicle
speeds. Total of spot speeds/No of vehicles.
Overall travel time
- Time travel including stop and delays.
Overall travel speed/journey speed (*)
- The speed over a specified section of
highway. Distance/overall travel time.
Definition:
O ti d (*)
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Operating speed (*)
- the highest overall speed a driver can travelunder a favorable weather condition w/outexceeds the speed limits
Running speed (*)
- the average speed maintained over a
particular distance which the vehicle is inmotion. Distance/ (Time traveltime delay)
Running delay- delay caused by interference between
components of traffic (stream flow, parking)
Design speed
- the speed determined for design as related to the
physical features of a highway that mightinfluence vehicle operation.
- the max safe speed that can be maintained overa specified section of highway when conditionsare so favorable.
Median speed
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Median speed
- speed at the middle value in a series of spot
speeds that are arranged in ascending order
Modal speed
- speed value with highest frequency
(observation) in a sample of spot speeds.
Pace/Mode
- the range of speed (5-10 km/h intervals) that has
the greatest number of observations.
Standard deviation of speeds
- measure of the spread of the individual speeds.
Space mean speed
- the arithmetic mean of speeds of vehicles
occupying a relatively long section of street or
highway at given instant.
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Analysis and data presentation(refer Ex 4.2 pg 93)
Table
Speed
group
Mean
speed, v
Frequency,
f
fv % f Cumulative %
f
f(v-u)2
1014.9 12.5 0 0 0
Histogram
frequ
ency
Speed, kph
Frequencydistribution
Cumulativedistribution
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Time mean speed vs. space mean speed
Time mean speed
= Total speed
No of vehicles
Space mean speed
= Total distance
Total time
Six vehicles traveling through a section of a ruralsecondary road with the speeds measured at 68, 71,79, 82, 76 and 74 km/h respectively. Assuming everyvehicle was traveling at constant speed over thesection of road, calculate the space mean speed and
time mean speed.
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Volume Studies
collect data on the no of vehicles and/orpedestrians that pass a point on a highway
facility during a specified time period.
Time periodlittle as 15 min to as much as ayear, depends on the use of the data.
Data collectedput into subclasses.
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Types of Traffic Daily Volume
Average Annual Daily Traffic (AADT)
Average 24 hour volume over a year
Average Annual Weekday Traffic (AAWT)
Average 24 hr volume occurring on weekdaysover a year
Average Daily Traffic (ADT)
Same as AADT, but average over period less
than a year, say, a monthAverage Weekday Traffic (AWT)
Same as AAWT, but average over period lessthan a year, say, a month
Applications of AADT/ADT
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Applications of AADT/ADT
AADT Applications1. Estimation of highway use
2. Estimation of trends
3. Economic feasibility evaluation4. Planning
5. Maintenance
ADT Applications
1. Planning of highway activities
2. Measurement of current demand
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Peak Hour Volume (PHV)
The max no of veh passing a point on ahighway over 60 consecutive minutes
Peak Hour Factor (PHF)
PHF = Peak hour volume4 x The maximum15 minute volume
Mainly used for urban:
1. Highway design (e.g. highway classification, noof lanes, signalization)
2. Traffic management (e.g. capacity analysis,parking)
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Volume Characteristics
Three basis of traffic flow:
1. Hourly
The traffic flow mostly for a daytrafficvolume varies from hour to hour.
2. Daily
Distribution of traffic flow every day fromSunday to Saturday in a week.
3. Monthly
Distribution of traffic flow for each monthfrom January to December in a year
Refer figure 4.14 pg 110 in your textbook
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Traffic Count
The duration can be 1 hour, 1 day or 1 year
Unit: no. of vehicle or passenger car unit
(PCU)
Traffic can be divided into type & class ofvehiclecar, motorcycle, bus, lorry, etc
PCUstandard unit of measurement
designed to give the effect of an
equivalent numbers of passenger cars.
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Methods of Conducting Volume Counts
Manual method
Involves one or more persons recording
observed vehicles using a counter. Advantages:a) not required specialized
b) accurate results
Disadvantages:a) labour intensivecan be expensive
b) cannot be use for long periods of counting
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Automatic Method
Laying of surface detectors (pneumatic road tubes)or subsurface detectors (magnetic or electriccontact devices) on the road.
Detect the passing vehicle & transmit the
information to a recorder. Advantages;
a) not required specialized
b) accurate results
Disadvantages;a) wear & tear
b) disrupts traffic during installation
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Types of Volume Counts
Cordon Counts* conduct at central business district (CBD).
* imaginary closed loop as cordon area.
* intersection crossing the cordon linecount station.
* Volume counts of vehicles enter & leavingcordon area are taken.
* data used: planning parking facilities,updating & evaluating traffic operationaltechnique.
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Screen Line Counts* study area are divided into large sections
by running imaginary lines (screen lines)across it.
* traffic counts are taken at each pointwhere a road crosses the screen line.
Intersection Counts* determine vehicle classifications through
movements & turning movements atintersections.
* determine phase lengths & cycle time forsignalized intersection, design ofchannelization.
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Analysis of Traffic Volume Data
Hourly Volume Characteristics
Flow(
pc
u/h/l)
Time (a.m-p.m)
7.00 8.00 9.00 10.00 11.00 12.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00
WeekdayWeekend
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Daily Volume Characteristics
Vehicleperday
Day per week
Sunday Monday Tuesday Wednesday Thursday Friday Saturday
Zone A
Zone B
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Flow
(pcu/h/l)
Year
1998 1999 2000 2001 2002 2003 2004 2005
Annually Volume Characteristics
-Increment of traffic
volume
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Definition
Design VolumeThe volume of traffic estimated to use the road during the designlife.
Design VehicleA selected motor vehicle which the weight, dimensions & operatingcharacteristics are used to establish highway design controls toaccommodate vehicles of a designated type.
Service volume
Max volume of traffic that a designed roadway would be able toserve without undue congestion falling below prescribed level ofservice (LOS) at the time the traffic is at design hourly volume.
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Highway capacity
Ability to accommodate traffic & usually expressed asno of vehicles that can pass a given point in a certainperiod of time at a given speed.
Level of service (LOS)Term used to classify the varying conditions of trafficflow that take place on highway. The various level ofservice range from the highest level (flow where drivers
are able to travel at their desired speed with freedom tomanoeuvre) to the lowest level (obtained duringcongested stop-start conditions).
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Level of service (LOS)
The LOS of existing highway may beevaluated by comparing measured trafficvolume to the capacity of that facilities.
Each road has its own capacity depending
on
a) speed
b) travel time
c) safetyd) traffic interruption
LOS = volume/capacity
F Fl
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Relationship of LOS to operating speed and Flow
A
B
C
D
E
F
Speed
Flow
Free Flow
Stable Flow
Approaching Unstable Flow
Unstable Flow
Forced Flow