In this document, we focus on the characteristics of the components comprising traffic systems, namely: Road Users, Vehicles, Infrastructure, Control Devices, and the environment.
Grade Separation and Weaving Segment Analysis
This module will cover the following topics:
1- Interchange Layout
2- Weaving segments analysis and Level of Service Assessment.
Conen 442 module1c: Capacity analysis and Level of ServiceWael ElDessouki
This module focuses on Capacity concepts and the Level of Service for transportation facilities. LOS analysis will be discussed for the multilane highway facility.
Tteng 441 traffic engineering fall 2021 part5Wael ElDessouki
Capacity analysis and design for signalized and un-signalized intersections. Level of Service at Signalized Intersection. Traffic control delay estimation.
Grade Separation and Weaving Segment Analysis
This module will cover the following topics:
1- Interchange Layout
2- Weaving segments analysis and Level of Service Assessment.
Conen 442 module1c: Capacity analysis and Level of ServiceWael ElDessouki
This module focuses on Capacity concepts and the Level of Service for transportation facilities. LOS analysis will be discussed for the multilane highway facility.
Tteng 441 traffic engineering fall 2021 part5Wael ElDessouki
Capacity analysis and design for signalized and un-signalized intersections. Level of Service at Signalized Intersection. Traffic control delay estimation.
In this module, we will discuss different techniques for lane management and the method for feasibility assessment.
Lane Reversal
High Occupancy Vehicle (HOV) Lane
Shoulder Lane
Often changes in the direction are necessitated in highway alignment due to various reasons such as topographic considerations, obligatory points.
The geometric design elements pertaining to horizontal alignment of highway should consider safe and comfortable movement of vehicles at the given design speed of the highway.
It is therefore necessary to avoid sudden changes in direction with sharp curves or reverse curves which could not be safely and conveniently negotiated by the vehicles at design speed.
Improper design of horizontal alignment of roads would necessitate speed changes resulting m higher accident rate and increase in vehicle operation cost.
Lucknow Metro is a rapid transit system under construction in the city of Lucknow,Lucknow Metro will have 2 Lines, the North-South line and the East-West line. The project will be the most expensive public transport system in the state. Total cost of phase 1 and 2 will be about $2 billion, of which ₹6,928 crore (US$1 billion) is being spent on phase 1.
Delhi metro Internship report on Elevated metro rail corridor This report will help all the Civil engineering students to make their report in their respective construction field.
For more details Contact me- bhargavashubham17@gmail.com
+918982669302
Geometric design of highways
Mr. Desai Akshay Prakash
Lecturer in civil engineering department
Sant Gajanan Maharaj Rural Polytechnic, Mahagaon.
contact-+91-9604713468
www.sgmrh.com
3-D Road Design by Applying Differential Geometry and Conventional Design Ap...Basil Psarianos
3-D Road Design by relating Differential Geometry parameters with conventional road design parameters like horizontal and vertical curvature and superelevation rate
Our project is the complete study about both Spot speed studies and Speed delay time survey. This topic is a part of Transportation Engineering. This report helps you to understand this topic in detail. This report will also help you to make project on associated topics in traffic engineering. In spot speed, We discussed regarding various methods available to perform the test, Our team practically performed test and established a speed limit zone near a school. Coming to speed delay time survey, we conducted a survey at a selected stretch and came out with solutions to the problems faced by the vehicle users using that stretch.
Traffic Engineering, PPT Based On Unit 1 (Fundamentals of Traffic Engg.)
In this PPT you Can studied about details of traffic engg, Characteristics , and others fundamentals of Road.
By- Prof K.S.Somase
(Assistant professor of Gurukul Education society's Institute of engineering and technology, Nandgaon
In this module, we will discuss different techniques for lane management and the method for feasibility assessment.
Lane Reversal
High Occupancy Vehicle (HOV) Lane
Shoulder Lane
Often changes in the direction are necessitated in highway alignment due to various reasons such as topographic considerations, obligatory points.
The geometric design elements pertaining to horizontal alignment of highway should consider safe and comfortable movement of vehicles at the given design speed of the highway.
It is therefore necessary to avoid sudden changes in direction with sharp curves or reverse curves which could not be safely and conveniently negotiated by the vehicles at design speed.
Improper design of horizontal alignment of roads would necessitate speed changes resulting m higher accident rate and increase in vehicle operation cost.
Lucknow Metro is a rapid transit system under construction in the city of Lucknow,Lucknow Metro will have 2 Lines, the North-South line and the East-West line. The project will be the most expensive public transport system in the state. Total cost of phase 1 and 2 will be about $2 billion, of which ₹6,928 crore (US$1 billion) is being spent on phase 1.
Delhi metro Internship report on Elevated metro rail corridor This report will help all the Civil engineering students to make their report in their respective construction field.
For more details Contact me- bhargavashubham17@gmail.com
+918982669302
Geometric design of highways
Mr. Desai Akshay Prakash
Lecturer in civil engineering department
Sant Gajanan Maharaj Rural Polytechnic, Mahagaon.
contact-+91-9604713468
www.sgmrh.com
3-D Road Design by Applying Differential Geometry and Conventional Design Ap...Basil Psarianos
3-D Road Design by relating Differential Geometry parameters with conventional road design parameters like horizontal and vertical curvature and superelevation rate
Our project is the complete study about both Spot speed studies and Speed delay time survey. This topic is a part of Transportation Engineering. This report helps you to understand this topic in detail. This report will also help you to make project on associated topics in traffic engineering. In spot speed, We discussed regarding various methods available to perform the test, Our team practically performed test and established a speed limit zone near a school. Coming to speed delay time survey, we conducted a survey at a selected stretch and came out with solutions to the problems faced by the vehicle users using that stretch.
Traffic Engineering, PPT Based On Unit 1 (Fundamentals of Traffic Engg.)
In this PPT you Can studied about details of traffic engg, Characteristics , and others fundamentals of Road.
By- Prof K.S.Somase
(Assistant professor of Gurukul Education society's Institute of engineering and technology, Nandgaon
Traffic engineering is that branch of engineering which deals with the improvement of
traffic performance on road network and terminals through systematic traffic studies,
scientific analysis and engineering applications which provide safe, rapid, efficient
convenient and economic transportation of persons and goods.
• Traffic engineering includes planning and geometric design on one hand and
regulation and control on the other.
• The road traffic is composed of different categories of vehicular traffic and pedestrian
traffic. Each category of vehicular traffic has two components, the human element as
the driver and the machine as the vehicle.
This PPT gives brief description of TESTING DIRECTORATE in R.D.S.O Manak Nagar Lucknow.
These includes all cells under this directorate.
I did my summer training under this directorate in 2017.
Highway and railway geometric design-Revised.pptxkiranmaqsood5
It the presentation about highway and railway geometric design. It describes the complete criteria for designing project. It about design streets and railways. how much carriageway is required for new road
Introduction to operations research and mathematical modeling. Development of linear programming mathematical model. Solving linear mathematical models using the graphical method and simplex method. Integer programming and solving integer models using branch and bound method.
Tteng 441 traffic engineering fall 2021 part3Wael ElDessouki
Traffic Studies: Spot speed study and analysis of speed data. Volume Studies: highway and intersection volume studies. Delay studies at signalized intersections.
Conen 442 module3 S2021 Pavement Design and Construction Wael ElDessouki
In this module, we present the two types of pavement commonly used, rigid and flexible pavements. The design and construction methods will be discussed also.
In this part, we focus on the fundamental objectives for the geometric design of roundabouts. Then we discuss the different checks to assess the safety of the roundabout geometric design.
Lec1: https://youtu.be/rMsXWw2BBv8
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
5. Introduction
Q: What is Traffic Engineering?
ElDessouki
CONEN 442 Transportation Engineering S2021
5
A: Definition from the Institute of Traffic
Engineers(ITE):
“The phase of transportation engineering that
deals with the planning, geometric design and
traffic operations of roads, streets, and highways,
their networks, terminals, abutting lands and
relationship with other modes of transportation”
9. Road User Characteristics:
Drivers & Pedestrians Limits
Road users are diverse population and have different
characteristics.
However, their characteristics follow a normal distribution, and,
in our analysis, we will focus on 85% & 15%
85th % represents the maximum
15th % represents the minimum
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CONEN 442 Transportation Engineering S2021
9
10. Drivers’ Field of Vision
10
CONEN 442 Transportation Engineering S2021 ElDessouki
11. 1- Road Users Visual Characteristics
Vision is the most important sensory system
for the task of driving a vehicle.
Q: Why?
A: Because drivers rely on their vision to:
1- Detect hazards
2- Make turn decisions
3- Selecting Acceleration/Deceleration Rates
4- Selecting safe Speed
…
Simply all driving decisions are based on their vision
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12. Vertical Field of Vision
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CONEN 442 Transportation Engineering S2021
12
75 Deg.
60 Deg.
Line of Sight
3-10 Deg.
Acute vision cone
10 - 12 Deg.
Clear vision cone
13. Field of Vision: Examples
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13
5 Deg. (Diameter)
10 Deg.
14. Horizontal Field of Vision
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14
90-100 Deg.
60 Deg.
16. Field of Vision Characteristics
Impact of Speed on Visual Field:
As speed increases, the visual field decrease significantly, especially
the peripheral vision.
Example:
at 20 mph it becomes 100 deg.
at 60 mph it becomes 40 deg.
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17. Field of Vision: Impact of Speed (24 km/hr)
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CONEN 442 Transportation Engineering S2021 17
18. Field of Vision: Impact of Speed (35 km/hr)
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19. Field of Vision: Impact of Speed (40 km/hr)
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20. Field of Vision: Impact of Speed (48 km/hr)
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CONEN 442 Transportation Engineering S2021 20
21. Field of Vision: “Importance”
Traffic Engineers Use Field of Vision for:
1. Traffic signs placement on highways
2. Traffic signs size
3. Safety analysis
Note: peripheral vision has the most important role in driver’s
speed perception
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23. Perception- Reaction Time (PRT)
Perception Time:
Can be defined as the time it takes a driver to sense, perceive,
and understand the existence and nature of a stimulus
Reaction Time:
Can be defined as the time it takes a driver to make a
response decision based on the nature of the existing stimulus
and his own state, and to execute that decision.
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24. Perception- Reaction Time (PRT)
Design Values:
2.5 seconds for most computations involving braking reactions. (90th %) (AASHTO)
1.0 second for signal timing purposes (85th %)(ITE)
NOTE: Higher values of PRT for more complex situations might be used (AASHTO)
AASHTO - American Association of State Highway and Transportation Officials
ITE – Institute of Traffic Engineers
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25. Perception- Reaction Time (PRT)
Factors Affecting Driver’s PRT :
1 – Age
2- Fatigue
3- Complexity of the situation
4 – Presence of Alcohol or Drugs in the driver’s
body
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27. Pedestrian Characteristics
Walking Speed:
1.22 m/s (4 ft/s) Recommended for Intersection Design (15 % Percentile )
accommodates 85%
1.5 m/s ( 5 ft /s) 50Th Percentile (Median)
Gap Acceptance:
Gap acceptance is defined as the acceptable distance gap between two
successive vehicles in a traffic stream the pedestrian is trying to cross.
Depends on:
perception of approaching vehicle speed
number of lanes & lane width
age & gender of pedestrian.
Recommended Design Value:
37.5 m (125 ft ) 85th percentile
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31. Vehicle Categories (AASHTO):
Buses:
intercity motor coaches, transit buses, school buses, and articulated buses
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31
Intercity Bus Transit Bus
Van/Small Bus Articulated Bus
School Bus
33. Vehicle Categories (AASHTO):
Recreational vehicles
motor homes, cars with various types of trailers (boat, campers, motorcycles, etc.)
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Motor Homes
Camper Trailer
Boat Trailer
JetSki Trailer
34. Low Speed Turning Characteristics
Low Speed Turning is governed by vehicle geometry.
Each design vehicle has the following critical attributes:
1. The minimum inner turning radius
2. Wheelbase width
3. The minimum outer turning radius
4. Path of front overhang
These attributed must be taken into consideration in the
geometric design of traffic facilities
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36. Low Speed Turning Characteristics
Application Example for Low Speed Turning Characteristics:
Accommodation of Bus at Signalized Intersection
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37. Low Speed Turning Characteristics
Application Example for Low Speed Turning Characteristics:
Accommodation of Truck at Signalized Intersection
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38. High-Speed Turning Characteristics
Relationship between Turning Speed, Radius of Curve, Superelevation, and Side
Friction:
Where ,
V – Vehicle Speed (m/s) ,
R- Curve Radius (m),
- Side Friction Coefficient
– Super elevation % ,
– Gravitational Acceleration(m/s2)
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0.01 + =
100
e
R
C.G.
39. High-Speed Turning Characteristics
Side Friction:
Side friction is affected by surface condition and vehicle speed.
For design purpose, wet condition is usually assumed. The following
table shows recommended values:
Note: 1 mile = 1.61 Km
Super elevation:
Typical range 0.5-12 % , but in most cases it does not exceed 8%
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41. High-Speed Turning Characteristics
Example:
Given the design speed for a highway , to be 120 km/hr. Please determine
the minimum radius for a horizontal curve, if the super elevation was
limited to be 3% & 8%.
Answer: e+f = v2/gR 120kph 120/3.6=33.33 m/s
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43. Vehicle Stopping Characteristics
When a driver sees a hazard, he will press the brake to stop the
vehicle and avoid collision:
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CONEN 442 Transportation Engineering S2021
43
The driver
sees the
hazard
Driver
Starts
Brake
Driver
Crash
Here
Decision Making Distance (d1)
Perception/Reaction Distance
d1 = *
Braking Distance (d2)
d2 =
Total Stopping Distance: ds = d1 + d2
Vi
Friction F = W*f= mg*f
Vf
Vi
44. Vehicle Stopping Characteristics
Total Stopping Sight Distance (Generic Units):
Where,
ds : Total Stopping Distance (m)
Vi : Initial Vehicle Speed (m/s)
Vf : Final Vehicle Speed (m/s)
g : Gravitational Acceleration (m/s2)
f : Pavement Longitudinal Friction Coefficient (0.348)
G : Vertical Grade %
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= +
= +
= ∗ +
−
2 ( ± 0.01 )
45. Vehicle Characteristics:
Traffic Light Application (General)
Yellow Time (Y):
All Red Time (AR) (Clearance Time):
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CONEN 442 Transportation Engineering S2021 45
2
Speed
Passing
Speed
Approach
Distance
Sight
Stopping
Y
Speed
Passing
Length
Vehicle
Distance
Passing
AR
46. Vehicle Characteristics:
Traffic Light Application
For Through Movement (TH) case:
The passing speed is the same as the approach speed, hence:
ElDessouki
CONEN 442 Transportation Engineering S2021 46
V
SSD
Speed
Approach
Distance
Sight
Stopping
Y
V
L
Width
Speed
Approach
Length
Vehicle
Distance
Passing
AR
V V
Width L
Stopping Sight Distance
(SSD)
47. V
R
LArc
Stopping Sight Distance
(SSD)
L
Vehicle Characteristics:
Traffic Light Application
For Left Turn Movement (LT) case:
The passing speed for the vehicle is the safe turning speed (Vt),
hence:
ElDessouki
CONEN 442 Transportation Engineering S2021 47
2
2
t
V
V
SSD
Speed
Turning
Speed
Approach
Distance
Sight
Stopping
Y
t
Arc
V
L
L
Speed
Passing
Length
Vehicle
Distance
Passing
AR
gravity
g
on
SideFricti
f
TurnRaduis
R
f
R
g
V
l
l
t
*
*
48. Vehicle Characteristics: Applications
Example:
For the shown intersection, please do the following:
For Through Movement (TH) Determine the Yellow time (Y) & Clearing
time (AR)
For Left Turn Movement (LT) Determine the Yellow time (Y) & Clearing
time (AR
Given:
Longitudinal skid friction coefficient = 0.348
Turning Radius (R) = 50 m
Lane width = 3.60 m, Median Width = 4 m
Approach Speed (V)= 60 km/hr ,
Assume Arc length for LT (LArc) =35 meters.
ElDessouki
CONEN 442 Transportation Engineering S2021 48
R
q 45
LArc
49. Example : Chapter 2
2.2
A driver traveling at 100 km/h rounds a curve on a
level grade to see a truck overturned across the
roadway at a distance of 120 m. If the driver is able to
decelerate at a rate of 0.31g , at what speed will the
vehicle hit the truck? Plot the result for reaction times
ranging from 0.50 to 5.00 s in increments of 0.5 s.
Comment on the results.
2.7
What minimum radius of curvature may be designed
for safe operation of vehicles at 110 km/h if the
maximum rate of superelevation (e) is 6% and the
maximum coefficient of side friction (f) is 0.10? ElDessouki
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52. Types of Traffic Streams:
Uninterrupted:
Uninterrupted flow facilities have no external
interruptions to the traffic stream. Pure uninterrupted
flow exists primarily on freeways, where there are no
intersections at grade, traffic signals, STOP or YIELD
signs, or other interruptions external to the traffic
stream itself.
Interrupted:
Interrupted flow facilities are those that incorporate
fixed external interruptions into their design and
operation. The most frequent and operationally
significant external interruption is the traffic signal.
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55. Macroscopic Parameters: Volume
Traffic Volume or Flow Rate:
Defined as the number of vehicles passing a point
on a highway, or a given lane or direction of a
highway, during a specified time interval.
Units: Vehicle / Time (hr, day, week , or year )
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56. Macroscopic Parameters: Daily Volumes
Average annual daily traffic (AADT):
The average 24-hour volume at a given location over a full 365-day year;
the number of vehicles passing a site in a year divided by 365 days.
Average annual weekday traffic (AAWT):
The average 24-hour volume occurring on weekdays over a full 365-day
year; the number of vehicles passing a site on weekdays in a year
divided by the number of weekdays (usually 260).
Average daily traffic (ADT):
The average 24-hour volume at a given location over a defined time
period less than one year; a common application is to measure an ADT
for each month of the year.
Average weekday traffic ( AWT):
The average 24-hour weekday volume at a given location over a defined
time period less than one year; a common application is to measure an
AWT for each month of the year.
NOTE:
Usually these values are in (veh./day) and non-directional
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57. Macroscopic Parameters: Daily Volumes
Typical Usage for Daily Volumes are:
Network Planning & Design.
Feasibility assessment for major projects.
Prioritization of maintenance projects.
Assessment of current Demand
Estimating Transportation trends and forecasting
future demand.
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59. Macroscopic Parameters: Hourly
Volumes
Daily traffic volumes ( ADT, AADT, ..etc) , are useful
for planning purposes but it can not be used for
design and operation of traffic facilities.
Why?
Because traffic volume varies significantly over the
24 hrs of the day, and the direction. Traffic facilities
must be designed to accommodate peak traffic
volume in the peak direction.
Therefore, for design:
We use the DDHV (Directional Design Hourly Volume) ElDessouki
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60. Macroscopic Parameters: DDHV
Estimation of DDHV
DDHV = AADT * K * D
Where,
AADT : Annual Average Daly Traffic Volume
K : Proportion of the traffic volume occurring during peak hour
D : Direction Proportion
Remember:
AADT is not directional, i.e. traffic flow on both direction of the road is counted
Question:
Why we don’t just count hourly volume and do our design?
Answer:
We usually do our design for future forecast volume. Most future demand forecasting is
carried out in terms of AADT
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60
61. Macroscopic Parameters: Peak Hour
Factor
Example showing a synthetic hourly traffic volume pattern for a weekday
in Jazan city
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0
100
200
300
400
500
600
700
800
900
12:00 AM 6:00 AM 12:00 PM 6:00 PM 12:00 AM
Traffic
Volume
(
veh/hr)
Time of Day (hrs)
Morning Peak Hour Afternoon Peak Hour
Average Daily Volume
62. Macroscopic Parameters: Peak Hour
Factor
Peak Hour:
Is defined as the single hour of the day that has the highest traffic flow
rate.
Estimating Peak Hour Factor (PHF):
1- Traffic volume is counted during the peak hour time frame in 15
minutes increments for a period of 2 hrs.
2- Identify the maximum consecutive 15 min intervals where the traffic
volume is the highest, this would be the Peak Hour
3- Add the traffic volume for the four intervals to get the hourly rate,
then
Where,
V – Hourly volume observed during peak hour
Vmax15 – The maximum volume counted during the 15 minutes intervals
of the peak hour
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=
( )
4 ∗
64. Macroscopic Parameters: Speed
Time Mean Speed ( TMS):
The average speed of all vehicles passing a point on a highway
or lane over some specified time period.
Space Mean Speed (SMS):
The average speed of all vehicles occupying a given section of
highway or lane over some specified time period.
Where,
n – number of observed vehicles
vi - Speed of vehicle i passing the observation station
d - length of traversed highway section
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n
v
n
t
d
TMS
n
i
i
n
i i
1
1
n
i
i
n
i
i t
nd
n
t
d
SMS
1
1
65. Macroscopic Parameters: Speed
Example
Veh. d (m) time(sec) Speed (m/sec)
1 500 10.4 48.08
2 500 6.6 75.76
3 500 8.2 60.98
4 500 9.4 53.19
5 500 10.3 48.54
6 500 6.1 81.97
7 500 11.8 42.37
8 500 6.1 81.97
Sum= 68.9 492.85
TMS = 61.61
SMS = 58.06
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Observations:
SMS are usually less than the TMS
SMS accounts for slower vehicle more than
the TMS
SMS considers the time vehicles occupy
the road
66. Macroscopic Parameters: Density
Traffic Density (D):
Defined as the number of vehicles occupying a
given length of highway or lane, generally expressed
as vehicles per km or vehicles per km per lane.
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68. Microscopic Parameters: Spacing &
Headway
Spacing (da):
Is defined as the distance between successive vehicles in a
traffic lane, measured from some common reference point on
the vehicles, such as the front bumper or front wheels.
Then density (D) would be:
Headway (ha):
Is defined as the time interval between successive vehicles as
they pass a point along the lane, also measured between
common reference points on the vehicles.
Then , flow rate (q) would be:
Average Speed (v ) would be:
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a
d
km
veh
D
1000
)
/
(
a
h
hr
veh
q
3600
)
/
(
)
/
(
*
6
.
3
)
/
( a
a h
d
D
q
hr
km
v
69. Relationship Between:
Flow Rate, Speed &Density
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Density
D
Speed
v
FlowRate
Q
Where
D
v
Q
s
S
,
*
Flow
Rate
Q
(veh/lane/hr)
Density
D (veh/lane/km)
Jam
Density
Critical
Density
0
Saturation Flow Rate
Congested
Flow
Stable
Flow
0
Free Flow
Speed
70. Relationship Between:
Flow Rate, Speed &Density
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Density
D
Speed
v
FlowRate
Q
Where
D
Q
v
s
s
,
/
Flow Rate
Q (veh/lane/hr)
Speed
v (km/hr)
0
Saturation Flow Rate
Congested
Flow
Stable
Flow
0
Free Flow
Speed
71. Relationship Between:
Flow Rate, Speed &Density
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Density
D
Speed
v
FlowRate
Q
Where
D
Q
v
s
s
,
/
Density
D (veh/lane/km)
Speed
v (km/hr)
0
0
Free Flow
Speed
Jam
Density
speed
flow
free
v
D
D
v
v
f
jam
f
1
*
Greenshield’s Model(1934):
Constant
Model
C
D
D
C
v
jam
ln
*
Greenberg’s Model(1959):
eed
FreeFlowSp
v
e
v
v
f
D
D
f
jam
*
Underwood’s Model(1961):
Speed/Density Models:
73. Traffic Control Devices:
Traffic control devices are the media by which traffic engineers
(communicate with drivers. Virtually every traffic law, regulation, or
operating instruction must be communicated through the use of
devices that fall into three broad categories:
Traffic markings
Traffic signs
Traffic signals
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74. Traffic Control Devices: MUTCD
Manual on Uniform Traffic
Control Devices (MUTCD)
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75. Traffic Control Devices: MUTCD
MUTCD define the Purpose of Traffic Control Devices:
“to promote highway safety and efficiency by providing
for orderly movement of all road users on streets and
highways, throughout the Nation.”
MUTCD define also the five requirements for a traffic
control device to be effective in fulfilling that mission:
1. Fulfill a need
2. Command attention
3. Convey a clear, simple message
4. Command respect of road users
5. Give adequate time for a proper response
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76. MUTCD Core Contents
1. Detailed standards for the physical design of the device,
specifying shape, size, colors, legend types and sizes, and
specific legend.
2. Detailed standards and guidelines on where devices should be
located with respect to the traveled way.
3. Warrants, or conditions, that justify the use of a particular
device.
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77. MUTCD Core Contents: Examples
1. Detailed standards for the
physical design of the
device, specifying shape,
size, colors, legend types
and sizes, and specific
legend.
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78. MUTCD Core Contents: Examples
2. Detailed standards and guidelines on where
devices should be located
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79. MUTCD Core Contents: Examples
3. Warrants, or conditions, that justify the use of a
particular device.:
STOP control Warrants (MUTCD 2009) :
Guidance: At intersections where a full stop is not necessary at all
times, consideration should first be given to using less restrictive
measures such as YIELD signs
The use of STOP signs on the minor-street approaches should be
considered if engineering judgment indicates that a stop is always
required because of one or more of the following conditions:
I. The vehicular traffic volumes on the through street or highway exceed 6,000
vehicles per day;
II. A restricted view exists that requires road users to stop in order to adequately
observe conflicting traffic on the through street or highway; and/or
III. Crash records indicate that three or more crashes that are susceptible to
correction by the installation of a STOP sign have been reported within a 12-
month period, or that five or more such crashes have been reported within a 2-
year period. Such crashes include right-angle collisions involving road users on the
minor-street approach failing to yield the right-of-way to traffic on the through
street or highway.
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80. MUTCD : Traffic Signs
Types of Traffic Signs:
Regulatory signs. Regulatory signs convey
information concerning specific traffic regulations.
Regulations may relate to right-of-way, speed limits,
lane usage, parking, or a variety of other functions.
Warning signs. Warning signs are used to inform
drivers about upcoming hazards that they might not
see or otherwise discern in time to safely react.
Guide signs. Guide signs provide information on
routes, destinations, and services that drivers may
be seeking.
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83. MUTCD : Traffic Signs
Warning signs. Warning signs are used to inform
drivers about upcoming hazards that they might not
see or otherwise discern in time to safely react.
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84. MUTCD : Traffic Signs
Warning signs. Warning signs are used to inform
drivers about upcoming hazards that they might not
see or otherwise discern in time to safely react.
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85. MUTCD : Traffic Signs
Guide signs. Guide signs provide information on
routes, destinations, and services that drivers may
be seeking.
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86. MUTCD : Traffic Signs
Guide signs. Guide signs provide information on routes,
destinations, and services that drivers may be seeking.
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