Transpo Module 1 - 5 Merged PDF

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GuiltlessHazel

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Southern Alberta Institute of Technology

2017

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transportation planning transportation systems road design civil engineering

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This document is a module on transportation planning, covering fundamentals, importance of systems, social costs, and road design. It discusses transportation background, including historical progress and modern issues, and analyzes the impacts of different transportation methods. Concepts also include driver factors and visual reception.

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CIVL 353 Transportation Planning Module 1: Fundamentals of Transportation Planning Transportation Planning How many planes are in the sky right now? © 2017, Southern Alberta Institute of Technology 2 Transportation Background Transportation is essential for a nation's deve...

CIVL 353 Transportation Planning Module 1: Fundamentals of Transportation Planning Transportation Planning How many planes are in the sky right now? © 2017, Southern Alberta Institute of Technology 2 Transportation Background Transportation is essential for a nation's development and growth. What is the role played by Transportation? ◦ Trade ◦ Commerce ◦ Conquest ◦ Travel ◦ Social Interaction What do YOU use Transportation for? ◦ Food – Work – Shopping – Personal Fulfillment (many many others) © 2017, Southern Alberta Institute of Technology 3 Transportation Planning Canada High Res Roads © 2017, Southern Alberta Institute of Technology 4 Transportation Background How has transportation progressed over the last 200+ years? ◦ Dirt Paths ◦ Gravel Paths ◦ Cobble Paths ◦ Dirt Roads ◦ Gravel Roads ◦ Cobble Roads ◦ Asphalt and Concrete Roads © 2017, Southern Alberta Institute of Technology 5 Transportation Background How has the reason for transportation progressed over the last 200+ years? ◦ Why did people travel in the year 100? ◦ Why did people travel in the 1500’s? ◦ Why did people travel in the early 1900’s? ◦ Why did people travel in the late 1900’s? ◦ Why do people travel today? © 2017, Southern Alberta Institute of Technology 6 Transportation Background How long did the very first transcontinental US trip take? California to New York ◦ 63 days: SOURCE How long would the same trip take today? ◦ 41 hours ◦ 25 Hours 39 Minutes is the record Google Maps © 2017, Southern Alberta Institute of Technology 7 Transportation Background How can we view today, the issues of 100 or 1000 years ago? Video Games ◦ Civilization ◦ Banished (Pre-Colonial) self-sustaining ▪ Colony self-sustaining ◦ Cities Skylines / CS 2 ▪ Modern Age ▪ Must worry about goods delivery and services on a city-wide scale ◦ American Truck Simulator/European Truck Simulator ▪ Delivering goods via semi-truck… and yes, this game exists © 2017, Southern Alberta Institute of Technology 8 Importance of Transportation Systems Natural Resources and markets Maintaining a competitive edge over other countries All linked to the quality of the transportation system © 2017, Southern Alberta Institute of Technology 9 Importance of Transportation Systems What kind of natural resources does Canada Export? Oil Cars Gas Gold Wood https://oec.world/en/profile/country/can © 2017, Southern Alberta Institute of Technology 10 Importance of Transportation Systems The Speed, Cost and Capacity of available transportation has a significant impact on the economic vitality of an area. Most developed and industrialized societies have been noted for high quality transportation systems. © 2017, Southern Alberta Institute of Technology 11 Importance of Transportation Systems 1900s British Empire ruled vast colonies located around the globe. Modern Day countries such as Canada, US, China, Japan, Europe are leaders in industry and commerce ◦ Transportation of goods does not assure success in the market, however if there is no services available, the country will suffer. © 2017, Southern Alberta Institute of Technology 12 Importance of Transportation Systems How were goods transported 200 years ago? ◦ Hand Delivered ◦ Hand Carts ◦ Horse and Buggy How are goods transported today? ◦ Shipping Containers / Cargo Vessels ◦ Railways ◦ Semi-Trucks and Highways © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 13 Importance of Transportation Systems © 2017, Southern Alberta Institute of Technology 14 Importance of Transportation Systems What is the best method? © 2017, Southern Alberta Institute of Technology 15 Importance of Transportation Systems What has been built to handle cargo ships? ◦ https://www.marineinsight.com/know-more/top-10- worlds-largest-container-ships-in-2019/ What has been built to handle trains? What has been built to handle semi-trucks? © 2017, Southern Alberta Institute of Technology 16 Importance of Transportation Systems Is there a faster method? ◦ Air What are the pros with Air Travel for a method of shipping goods? What are the cons with Air Travel for a method of shipping goods? © 2017, Southern Alberta Institute of Technology 17 Importance of Transportation Systems What happens when these systems fail? ◦ https://www.youtube.com/watch?v=E7t5yj1rScI&ab_channel= CNBC ◦ https://www.youtube.com/watch?v=Ty- m4pm8oog&ab_channel=PracticalEngineering ◦ https://globalnews.ca/news/1338351/15-compelling-images- of-canmore-in-the-2013-flood/ ◦ https://globalnews.ca/tag/train-derailment/ © 2017, Southern Alberta Institute of Technology 18 Importance of Transportation Systems Advancements in Technology ◦ What new Technology could Assist? Self Driving Vehicles Unmanned Delivery Vehicles Faster Methods of Delivery ◦ High Speed Rail? San Francisco Driverless Cars © 2017, Southern Alberta Institute of Technology 19 Social Costs of Transportation Systems Lots of change is coming in the next 10 years. ◦ Shipping and Freight account for a large portion of Greenhouse Gas. Approx. 28% © 2017, Southern Alberta Institute of Technology 20 Social Costs of Transportation Systems Transportation Systems do not come without costs. ◦ Land Usage, just how much land does your Airport, Railyard, Shipyard, Roadways take up? ◦ Where are they usually located? ◦ ~30% of usable land is given up for Roads ◦ ~50% of usable land is given up to transportation in general ◦ Pollution ◦ Noise ◦ Deaths ◦ Spoil the Natural Beauty of an Area © 2017, Southern Alberta Institute of Technology 21 Social Costs of Transportation Systems Calgary is about 825 sq. km. ◦ YYC is 15.6 sq. km ◦ ~1.9% of the land area of Calgary ◦ https://cnebusiness.geomapguide.ca/ ◦ https://www.acwr.com/economic-development/rail- maps/canadian-pacific © 2017, Southern Alberta Institute of Technology 22 Social Costs of Transportation Systems Transportation Systems are extremely expensive. ◦ Construction Costs (West RR ~ $1.2B) ◦ Kickinghorse Canyon ~ $600m ◦ Maintenance and Upkeep Costs ◦ Replacement Costs © 2017, Southern Alberta Institute of Technology 23 Social Costs of Transportation Systems Society has indicated a willingness to accept the risks of these systems in order to gain the advantages that result from them. ◦ The major goal of the transportation designer is to balance society’s need for a fast, effective system with the costs involved. The most efficient and cost- effective system is created without causing undue stress on the environment. $$$ NJB: Trucks Killing Us Mobility Environment © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 24 History of Roads The structure of the road has not changed in the last 1000 years. Still built as a crowned road, still incorporate drainage gravel and still include compacted earth. Methods, Materials and Equipment have changed © 2017, Southern Alberta Institute of Technology 25 Road Design Four Main Components of the Highway Mode of Transportation ◦ The Driver ◦ The Pedestrian ◦ The Vehicle ◦ The Road To provide efficient and safe highway transportation, a knowledge of the characteristics and limitations of each is essential. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 26 Road Design – The Driver Drivers’ skills and abilities vary greatly. People have a wide range of ability to see, hear, evaluate and react to information. These abilities are not only based on age and health, but fatigue and time of day. Age (14-80? / 90??) Design Criteria for highways must not be based on the best-case scenario but must be compatible with the abilities and limitations of most drivers. We design and build to the “average” driver. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 27 Road Design – The Driver Other Present Issues ◦ Alcohol Use ◦ Substance Use ◦ Distractions ▪ Kids ▪ Books ▪ Cell Phones ▪ Food ▪ (ect) Distracted Driving Distracted Driving 2 © 2017, Southern Alberta Institute of Technology 28 Source: Garber & Hoel, 2010, p. 59 and 60 Road Design – The Driver Human Response Process ◦ The Human Response Process has been evaluated and used in the process of highway design. ◦ Just how attentive are you? ◦ Refers to the actions taken by drivers based on their evaluation and reaction to the information that they obtain. ◦ Based on visual and hearing reception. https://www.alberta.ca/stopping-time-and- distance.aspx © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 29 Road Design – The Driver Visual Reception ◦ The most important source of information for a driver. ◦ The eye varies greatly in its ability to receive information. ◦ The characteristics that cause this variance are… ▪ Visual Acuity – Defined as the ability to see fine detail – There are two types, stationary and moving – Stationary visual acuity is dependent on background brightness, contrast and time. – The eye takes between 0.5 and 1.0 seconds to identify stationary objects. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 30 Road Design – The Driver Perception Reaction time of 2.5 seconds for design. Biological influence behind the wheel is the biggest factor. Quality and Size of Car ◦ New Good Quality Tires stop faster ◦ Old Bald Tires stop slower ◦ Winter vs Summer Tires Design Criteria from the 1950’s ◦ Car technology has advanced, so not much of a factor anymore ◦ Worst car on the road in 2020 is better than the best car in 1950 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 31 Road Design – The Driver © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 32 Road Design – The Driver Visual Reception ◦ The ability to detect moving objects depends on dynamic acuity. ◦ The eye has a cone of vision of 3 to 5 degrees where sight is clear. ◦ Within 12 degrees it is clear and beyond that is blurry © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 33 Road Design – The Driver Peripheral Vision ◦ The ability to see objects beyond the cone of clearest vision. ◦ Detail and color in this area are not clear ◦ After Age 60, significant changes occur © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 34 Road Design – The Driver Color Vision ◦ The ability to differentiate colors ◦ It is not of great importance as people can recognize traffic information by shapes and graphics © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 35 Road Design – The Driver Glare Vision ◦ This can be either direct light or reflection. ◦ Can result in a decrease of visibility and discomfort to your eyes. ◦ After age 40, significant changes occur, and eyes are more sensitive to glare. ◦ The time to recover from glare varies from 3 to 6 seconds. It usually takes 3 seconds to recover when moving from dark to light and 6 seconds when moving from light to dark. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 36 Road Design – The Driver Depth Perception ◦ This affects the ability to estimate speed and distance. ◦ Depth perception is important on a 2-lane passing highway where head-on accidents occur due to a lack of judgement concerning speed and distance. ◦ Harder to gauge this at night. Hearing Reception ◦ Not as important as vision because most information is received visually. ◦ Hearing does become important when warning sounds should be detected. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 37 Perception Reaction Process Perception ◦ Driver sees a control device, warning or information sign, or object on the road. Identification ◦ Driver identifies the object and understands. Emotion ◦ Driver decides what action to take (brake, pass, swerve, change lanes) Reaction ◦ Driver executes the action © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 38 Vehicle Characteristics Static characteristics of a vehicle include the weight and size. Size affects design standards for physical dimensions of a highway (lane width, shoulder width, length of curves). Axle weights are considered when pavement thickness and maximum grades are calculated. Minimum turning radius are dependent on the size of the vehicle. https://www.youtube.com/watch?v=wUxo2KmO4OI&t=308s&ab_channe l=EngineeringExplained © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 39 Pedestrian Characteristics Pedestrian characteristics may influence the design and location of pedestrian control devices such as signals, safety zones and traffic islands at intersections. Apart from visual and hearing characteristics, walking characteristics play a major part in the design of some of these controls. Walking speeds vary between 0.9 and 2.4 m/s. A value of 1.22 m/s is normally used for design purposes. In areas where the percentage of elderly pedestrians is greater than 20 percent, the average walking speed is reduced to 0.9 m/s © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 40 Road Characteristics Kinematic ◦ Characteristics which affect the motion of a vehicle without considering the forces that affect it. ◦ The main kinematic characteristic is the acceleration capacity. ◦ Acceleration is important in passing maneuvers. Dynamic ◦ The forces that act on a vehicle when it is in motion are: For example, when driving ▪ Air Resistance downhill on a 5% grade, you will ▪ Grade Resistance need approximately 5.6 meters ▪ Rolling Resistance more to stop your car than ▪ Curve Resistance stopping on a 3% grade. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 41 Road Characteristics Deadman Pass Oregon © 2017, Southern Alberta Institute of Technology Source: Google Maps 42 Road Characteristics Coquihalla Highway BC © 2017, Southern Alberta Institute of Technology Source: Google Maps 43 Road Characteristics Shelter Bay Ferry © 2017, Southern Alberta Institute of Technology Source: Google Maps 44 Road Characteristics White Rock BC © 2017, Southern Alberta Institute of Technology Source: Google Maps 45 Planning Process The process of transportation planning involves the elements of situation and problem definition, the search for solutions and performance analysis. As well as evaluation and choice of project. The process is useful for describing the effects of a proposed transportation alternative and for explaining the benefits to the traveler of a new transportation system and its impacts on the community. Highway designers are responsible for developing forecasts of travel demand, conducting evaluations based on economic and non-economic factors, and identifying alternatives for short, medium and long-range purposes. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 46 Planning Process Situation Problem Search for Definition Definition Solutions Choice of Evaluation of Analysis of Project Alternatives Performance Specification and Construction © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 47 Planning Process Situation Problem Search for Definition Definition Solutions Situation Definition ◦ Where is the problem? Choice of Project Evaluation of Alternatives Analysis of Performance ▪ Inventory of Existing Infrastructure ▪ Measure Travel Patterns Specification and ▪ Review Prior Studies Construction © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 48 Planning Process Situation Definition ◦ City involves the public © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 49 Planning Process Situation Problem Search for Definition Definition Solutions Problem Definition ◦ What is the cause of the Choice of Project Evaluation of Alternatives Analysis of Performance problem? ◦ Define Objectives Specification and Construction ◦ Establish Criteria ◦ Define Constraints ◦ Establish Design Standards © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 50 Planning Process Situation Problem Search for Definition Definition Solutions Search for Solutions ◦ What can you do to fix this? Choice of Project Evaluation of Alternatives Analysis of Performance ◦ Consider All Options ◦ The “Do Nothing” option must Specification and Construction also be considered. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 51 Planning Process Situation Problem Search for Definition Definition Solutions Analysis of Performance ◦ Measure and Model all options Choice of Project Evaluation of Alternatives Analysis of Performance ◦ Determine Costs, Traffic Flow and Impacts Specification and Construction ◦ Put Engineering Skills to work! © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 52 Planning Process © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 53 Planning Process Situation Problem Search for Definition Definition Solutions Evaluation of Alternatives ◦ Compare the Options. What is Choice of Project Evaluation of Alternatives Analysis of Performance Important? ◦ Determine benefit vs Cost, Specification and Construction profitability and cost effectiveness. ◦ Cost is sometimes difficult to evaluate with transportation projects. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 54 Planning Process Situation Problem Search for Definition Definition Solutions Choice of Project ◦ Consider factors including Choice of Project Evaluation of Alternatives Analysis of Performance revenue cost, site location and political judgment. Specification and Construction © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 55 Planning Process Situation Problem Search for Definition Definition Solutions Specification and Construction Choice of Project Evaluation of Alternatives Analysis of Performance ▪ Design and Construction Plans ▪ Operation and Maintenance Specification and Construction © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 56 Induced Demand Adding Capacity to the existing road network tends to also add new drivers to the roadway. Adding more lanes is not usually the solution. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 57 Induced Demand “We found that there’s this perfect one-to-one relationship,” said Turner. If a city had increased its road capacity by 10 percent between 1980 and 1990, then the amount of driving in that city went up by 10 percent. If the number of roads in the same city, then went up by 11 percent between 1990 and 2000, the total number of miles driven also went up by 11 percent. It’s like the two figures were moving in perfect lockstep, changing at the same exact rate. Turner and Duranton argue, is what they call the fundamental law of road congestion: New roads will create new drivers, resulting in the intensity of traffic staying the same. But the data showed that even in cities that expanded public transit, road congestion stayed the same. Add a new subway line and some drivers will switch to transit. But new drivers replace them. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 58 Induced Demand For instance, Paris in recent decades has had a persistent policy to dramatically downsize and reduce roadways. “Driving in Paris was bad before,” said Duranton. “It’s just as bad, but it’s not much worse.” So where did those other drivers go? Many of them switched to public transit, which in Paris has increased by 20 percent in the last two decades. Other trips have simply been avoided or done on foot. in Seoul, South Korea, where the city tore down a highway that was considered a vital roadway corridor, carrying 168,000 cars per day. After replacing the cars with a river, parkland, and some smaller roads, traffic didn’t get worse and many other things, including pollution, got better. Sometimes the best solution is to let the existing roads continue to be bad. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 59 Value of Time What is the value of your time when choosing your method of transport? ◦ Driving to SAIT? ▪ It would take me 20 minutes ▪ Gas? ▪ Parking? ▪ Insurance and Maintenance Costs ◦ Transit to SAIT? ▪ It would take me 53-64 minutes ▪ Transit Pass ▪ Parking? ▪ Walking? © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 60 Value of Time ◦ Calgary 1998 Cost of Time = $11.45/hr ▪ https://www.bankofcanada.ca/rates/related/inflation- calculator/ ◦ Calgary 2022 Cost of Time = $19.23/hr ▪ If you save 20 seconds on a trip, what is that worth? – (19.23/3600) x 20 = $0.11 ▪ If you save 10 minutes on a trip, what is that worth? – (19.23/60) x 10 = $3.21 ◦ While saving 11 cents does not seem like a lot, multiply it by the number of people who are saving that amount of time. ▪ 0.11 x 150,000 = $16,500 ▪ 11 cents and 150,000 people per day using the solution ▪ $16,500 x 365 = $6,022,500 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 61 Value of Time ◦ West Ring Road ▪ Reported to Save 20 minutes for people travelling North to West © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 62 Value of Time “An effective network of roads and highways fosters the safe, efficient movement of people and goods and contributes to Alberta's economy. Roads and highways directly connect to other transportation modes and are vital to moving Alberta's products to markets both within and outside the province. Alberta Transportation is responsible for the long-term planning of the highway network and oversees the network's design, construction, and maintenance activities.” For details on Alberta Transportation visit https://www.alberta.ca/transportation-and-economic- corridors.aspx © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p. 59 and 60 63 © 2017, Southern Alberta Institute of Technology. All rights reserved. This publication and materials herein are protected by applicable intellectual property laws. Unauthorized reproduction and distribution of this publication in whole or part is prohibited. For more information, contact: Director, Centre for Instructional Technology and Development Southern Alberta Institute of Technology 1301 16 Ave. N.W., Calgary, AB T2M 0L4 CIVL 353 Transportation Planning Module 2: Forecast Traffic Flows Traffic Modeling Using Mathematical equations to try to predict the behavior of humans within the transportation system. © 2017, Southern Alberta Institute of Technology 2 Traffic Modelling Delay formula for Two Way Stop Intersections: Module 20 3600 𝑣𝑥 2 3600 𝑣𝑥 𝑣𝑥 𝑐𝑚,𝑥 𝑐𝑚,𝑥 𝑑𝑥 = + 900𝑇 −1+ −1 + +5 𝑐𝑚,𝑥 𝑐𝑚,𝑥 𝑐𝑚,𝑥 450𝑇 © 2017, Southern Alberta Institute of Technology 3 Traffic Modeling Trip generation is the process of determining the number of trips that will begin or end in each traffic analysis zone within a study area. Trip generation is the first step in the 4-step transportation model. © 2017, Southern Alberta Institute of Technology 4 Traffic Modeling Travel demand is expressed as the number of persons or vehicles per unit time that can be expected to travel on a given segment of a transportation system under a set of given conditions. Forecasts of travel demand are used to establish the vehicular volume on future or modified transportation system alternatives. Source: Garber & Hoel, 2010, p.591 © 2017, Southern Alberta Institute of Technology 5 Traffic Modeling City of Calgary Traffic Volume Maps ◦ Link on D2L ◦ https://www.calgary.ca/planning/transportation/traffic-volume-flow-maps.html ◦ Other info on D2L – Road Classifications Source: City of Calgary © 2017, Southern Alberta Institute of Technology 6 Traffic Modeling Columbia River Bridge Crossings Source: Garber & Hoel, 2010, p.591 © 2017, Southern Alberta Institute of Technology 7 Traffic Modeling The methods of forecasting travel demand can range from a simple extrapolation of observed trends to a sophisticated computerized process involving extensive data gathering and mathematical modelling. Travel demand forecasting process is as much of an art as it is a science as judgements are required concerning the various parameters that provide the basis for a travel forecast. Source: Garber & Hoel, 2010, p.591 © 2017, Southern Alberta Institute of Technology 8 Traffic Modeling Since trips are determined without regard to destination. Each trip has two ends, and these are described in terms of trip purpose, or whether the trips are either produced by a traffic zone or attracted to a traffic zone. For example, a home-to-work trip would be considered to have a trip end produced in the home zone and attracted to the work zone. Trips are broken into productions and attractions ◦ Productions – Where the trip started ◦ Attractions – Where the trip ended Source: Garber & Hoel, 2010, p.591 © 2017, Southern Alberta Institute of Technology 9 Traffic Modeling What happened during Covid? ◦ Work from Home – Roads were Empty! ◦ Businesses Closed ◦ Restaurants Closed ◦ Schools Closed What was your commute like during Covid? Where did you drive during Covid? © 2017, Southern Alberta Institute of Technology 10 Traffic Modeling Urban demand forecasts, when first developed required that extensive databases be prepared using home interview and/or roadside interviews to gather insight concerning the characteristics of the trip maker, such as… ◦ Age and Sex ◦ Income ◦ Auto Ownership © 2017, Southern Alberta Institute of Technology 11 Traffic Modeling Skyscraper Downtown – High Paying Jobs ◦ Quality of the Job will influence from where the trips are generated. ◦ More High Paying Jobs will result in More Trips ◦ High Paying Jobs will result in larger – more expensive vehicles Strip Mall – Low Paying Jobs © 2017, Southern Alberta Institute of Technology 12 Traffic Modeling Two different areas… ◦ What kind of transportation would you expect out of these places during the morning rush? “The three factors that influence the demand for urban travel are: 1. The location and intensity of land use. 2. The socioeconomic characteristics of people living in the area. 3. The extent, cost, and quality of available transportation services. Land-use characteristics are a primary determinant of travel demand as the amount of traffic generated by a parcel of land depends on how the land is used. For example, shopping centers, residential complexes, and office buildings produce different traffic generation patterns.” © 2017, Southern Alberta Institute of Technology 13 Traffic Modeling The availability of transportation facilities and services, referred to as the supply, also affects the demand for travel. Travelers are sensitive to the level of service provided by alternative transportation modes. When deciding to travel at all or which mode to use, they consider attributes such as travel time, cost, convenience, comfort and safety. © 2017, Southern Alberta Institute of Technology 14 Traffic Modeling What places within the City of Calgary do you think are trip generators? Bow Valley SAIT U of C Heritage Park College Calaway Park Shopping Malls Strip Malls Airport Places of Zoo Telus Spark High Schools Employment Canada Olympic Mount Royal Scotiabank McMahon Park University Saddledome Stadium © 2017, Southern Alberta Institute of Technology 15 Traffic Modeling Where do you travel? © 2017, Southern Alberta Institute of Technology 16 Traffic Modeling Where do you travel? © 2017, Southern Alberta Institute of Technology 17 Traffic Modeling How many people attend SAIT daily? ◦ 15,000 Full Time ◦ 2,000+ Staff? ◦ What areas of the city do they come from? ▪ ALL areas… plus outlying communities. © 2017, Southern Alberta Institute of Technology 18 Traffic Modeling Every community in Calgary will contribute some trips to SAIT. ◦ Closer communities will contribute more. No one wants to drive in from Airdrie every day! ◦ Students choose to live closer to SAIT because it makes their life so much easier. © 2017, Southern Alberta Institute of Technology 19 Traffic Modeling Humans are Predictably Unpredictable ◦ If I need to go to Costco, I have numerous options ◦ Starting at SAIT, which one do I go to? ▪ The closest one? ▪ The least busy one? ▪ The one that is fastest to get to? All 6 stores in the map are feasible to get to from SAIT. ◦ Personal Bias © 2017, Southern Alberta Institute of Technology 20 Traffic Modeling Decision Made… ◦ Beacon Hill Costco How do I get there? ◦ Drive (~20 mins) ◦ Transit (48-70 mins) ◦ Uber/Taxi (~20 mins plus $$) ◦ Walk (3 hours) ◦ Bike (65 mins) © 2017, Southern Alberta Institute of Technology 21 Traffic Modeling Decision Made… ◦ Beacon Hill Costco ◦ Drive (~20 mins) Which route do I take? ◦ Stoney Trail ◦ Crowchild Trail ◦ Sarcee Trail ◦ Shaganappi Trail ◦ 14th Street ◦ Deerfoot Trail © 2017, Southern Alberta Institute of Technology 22 Traffic Modeling Decision Made… ◦ Beacon Hill Costco ◦ Drive (~20 mins) ◦ Sarcee Trail © 2017, Southern Alberta Institute of Technology 23 Traffic Modeling What could influence my decision? What factors do I need to think about while making my decision? ◦ Traffic ◦ Amount of Traffic Lights ◦ Distance ◦ Speed ◦ Fuel Usage ◦ Time Taken © 2017, Southern Alberta Institute of Technology 24 Traffic Modeling Google… who uses this? ◦ Live updates on traffic… ◦ Suggest alternate routes… ▪ Even if they take longer… – Seriously.. ◦ Shows fuel efficient routes ◦ Gives multiple options ◦ Will detour you out of your comfort zone if it saves you time. ◦ https://www.boredpanda.com/fake-traffic-jam-99-smartphones-google-maps-simon- weckert/?utm_source=google&utm_medium=organic&utm_campaign=organic © 2017, Southern Alberta Institute of Technology 25 Traffic Modeling © 2017, Southern Alberta Institute of Technology 26 Traffic Modeling Given options, technology and other factors, trip planning on a personal basis is difficult. However, humans on a large scale are quite predictable. ◦ The majority of people will take the fastest / most comfortable route, regardless of any other factors. Look at the major routes during rush hour. © 2017, Southern Alberta Institute of Technology 27 Traffic Modeling How much traffic will a given area generate? https://itetripgen.org/Query ◦ Dependent on… ▪ Location and Intensity of Land Use ▪ Socioeconomic characteristics ▪ Extent, Cost and Quality of available transportation services ◦ Land Use Characteristics ▪ Shopping Centers ▪ Residential Complexes ▪ Office Buildings ◦ Other factors ▪ Travel Time ▪ Cost ▪ Convenience ▪ Comfort © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 28 ▪ Safety Traffic Modeling Socioeconomic ◦ Low Income ◦ Med Income ◦ High Income ◦ Cars ◦ Disposable Income ◦ Luxuries ◦ Trips Per Day © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 29 Trip Generation (AM Peak) This is the output for the Trip Generation Step. P’s and A’s for each Zone. Balancing Trip Productions and Attractions Zone 1 t=15mins Zone 2 “In a perfect world the P=250 P=50 productions and attractions A=500 would balance however in A=150 most studies this is rarely the case. Stray trips get lost to outside zones so typically the data has to be ‘calibrated’. t=10mins t=10mins Trip productions, which are based on census data, are more accurate than trip attractions and accordingly Zone 4 Zone 3 trip attractions are usually modified so that they are P=300 P=400 equal to trip productions.” A=100 A=250 t=15mins © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 30 Trip Generation (AM Peak) Trip distribution is a process by which the trips generated in one zone are allocated to other zones in the study area. Trip Distribution is the second step in the 4-step transportation model. These trips may be within the study area (internal-internal) or between the study area and areas outside the study area (internal-external) Several basic methods are used for trip distribution. Among these are the gravity model, growth factor models, and intervening opportunities. The gravity model is preferred (and the one we will look at in this class) because it uses the attributes of the transportation system and land-use-characteristics and has been calibrated extensively for many urban areas. It has achieved virtually universal use because of its simplicity, its accuracy, and its support. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.606 31 Traffic Modeling Gravity Model Formula 𝐴𝑗 𝐹𝑖𝑗 𝐾𝑖𝑗 𝑇𝑖𝑗 = 𝑃𝑖 σ𝑗 𝐴𝑗 𝐹𝑖𝑗 𝐾𝑖𝑗 Tij = Number of trips produced in zone i, and attracted to zone j Pi = Total number of trips produced in zone i Aj = Number of trips attracted to zone j Fij = A value which is an inverse function of travel time Kij = Socioeconomic adjustment factor for interchange ij © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.604 32 Traffic Modeling Gravity Model Formula 𝐴𝑗 𝐹𝑖𝑗 𝐾𝑖𝑗 𝑇𝑖𝑗 = 𝑃𝑖 σ𝑗 𝐴𝑗 𝐹𝑖𝑗 𝐾𝑖𝑗 Fij represents the reluctance of persons to make trips of various durations or distances in that as travel time increases, the willingness to make the trip decreases. 1 1 1 Fij = Fij = Fij = t 2 (ti , j ) (t i , j ) (e) i , j © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.604 33 Traffic Modeling Gravity Model Formula 𝐴𝑗 𝐹𝑖𝑗 𝐾𝑖𝑗 𝑇𝑖𝑗 = 𝑃𝑖 σ𝑗 𝐴𝑗 𝐹𝑖𝑗 𝐾𝑖𝑗 Kij represents the socioeconomic factor since it accounts for variables other than travel time. For this class we will assume Kij = 1 for all zones. There are Desirable and Undesirable zones. You will go out of your way to go to a more desirable area. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.604 34 Trip Generation 4 zone network Zone 1 will produce 250 trips. Where are they going? Some will go to Zone 2, some to Zone 3 and some Zone 1 t=15min Zone 2 P=250 P=50 to Zone 4. A=150 A=500 Predict the percentage of trips going to the other t=10min t=10min zones. It all depends on the Zone 4 Zone 3 distance and attractiveness P=300 P=400 of those Zones. A=100 t=15min A=250 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 35 Trip Generation Zone 1 will produce 250 trips. Where are they going? Zone 1 t=15min Zone 2 P=250 P=50 A=150 A=500 t=10min t=10min Distribution based on Attractions alone. Does not take into account travel time. Zone 4 Zone 3 P=300 P=400 A=100 t=15min A=250 147.058824 %= = 58.82% 250 Zone 1 to 2 250 𝑥 500 𝑇1,2 = = 147.058824 500+100+250 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 36 Trip Generation Zone 1 will produce 250 trips. Where are they going? 𝑃1 𝐴2 ൘𝑡 2 1,2 𝑇1,2 = 𝐴1 0 𝐴2 𝐴3 𝐴4 2 + 2 + 2 + 2 𝑡1,1 𝑡1,2 𝑡1,3 𝑡1,4 This term represents all the trips t=15min from zone 1 to zone 1. We do Zone 1 Zone 2 P=250 P=50 not consider internal trips in our A=150 A=500 model therefor the value will be t=10min t=10min set to 0 and left out of the calculation Zone 4 Zone 3 P=300 P=400 A=100 t=15min A=250 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 37 Trip Generation Zone 1 will produce 250 trips. Where are they going? Zone 1 t=15min Zone 2 P=250 P=50 A=150 A=500 t=10min t=10min Distribution based on Travel Time alone Zone 4 Zone 3 P=300 P=400 A=100 t=15min A=250 144.4043 Zone 1 to 2 %= = 57.76% 250 250 𝑥 500 152 𝑇1,2 = 500 250 100 = 144.4043 + + 152 202 102 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 38 Trip Distribution 𝑃4𝐴5 𝑡4,52 𝑇4,5 = 𝐴1 𝐴2 𝐴3 𝐴4 𝐴5 𝐴6 𝐴7 𝐴8 + + + + + + + 𝑡4,12 𝑡4,22 𝑡4,32 𝑡4,42 𝑡4,52 𝑡4,62 𝑡4,72 𝑡4,82 2 3 1 5 4 6 7 8 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 39 Trip Distribution That was the equation for a 8 zone network; Just imagine what the equation would look like for our city with its 1868 zones. © 2017, Southern Alberta Institute of Technology 40 Trip Distribution How many calculations would you need for a 4 zone network? 4 zones x (4-1 zones) = 12 calculations What about Calgary’s 1868 zones? ◦ 1868*1867 = 3,487,556 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 41 Trip Distribution Origin Destination Table An Origin/Destination table is show below Destination (to) zone Origin (From) Zone 0 1 2 3 4 5 6 7 8 9 Total 0 1659 129 628 1953 467 243 110 719 991 6899 1 816 1786 214 757 1443 1385 1183 1002 1286 9872 2 894 360 1620 1371 1536 1211 1614 1796 605 11007 3 1262 706 1229 1893 466 1719 108 1637 709 9729 4 208 260 350 1370 1568 1368 1343 1516 1297 9280 5 1163 1531 416 1211 1894 1102 1218 191 537 9263 6 1503 1064 712 232 1453 1685 1754 621 1666 10690 7 385 1961 249 1335 620 18 1787 1514 203 8072 8 252 639 323 358 1210 399 1233 1468 1545 7427 9 287 674 857 1243 189 1705 1023 135 1795 7908 Total 6770 8854 6051 8211 11340 9287 11071 8933 10791 8839 How many people want to travel from – Zone 3 to 5? – Zone 4 to 8? – Zone 2 to 9? © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 42 Mode Choice Mode choice is that aspect of the demand analysis process that determines the number of trips between zones that are made by automobile and transit. The selection of one mode or another is a complex process that depends on factors such as traveler’s income, the availability of transit service or auto ownership, and the relative advantages of each mode in terms of travel time, cost, comfort, convenience and safety. Mode choice models attempt to replicate the relevant characteristics of the traveler, the transportation system, and the trip itself, such that a realistic estimate of the number of trips made by each mode for each zonal pair is obtained. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.592 43 Mode Choice Since public transportation is a vital component in urban areas, mode choice calculations typically involve distinguishing trip interchanges as either auto or transit. The following models are discussed in Section 12.4 of the textbook, and you are encouraged to read up on them. ◦ Direct Generation Models ◦ Trip End Models ◦ Trip Interchange Models ◦ Logit Models The complexity of this material is beyond the scope of this course. No mathematical solutions will be presented. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 44 Mode Choice © 2017, Southern Alberta Institute of Technology 45 Mode Choice © 2017, Southern Alberta Institute of Technology 46 Mode Choice © 2017, Southern Alberta Institute of Technology 47 Mode Choice © 2017, Southern Alberta Institute of Technology 48 Mode Choice © 2017, Southern Alberta Institute of Technology 49 Mode Choice © 2017, Southern Alberta Institute of Technology 50 Traffic Assignment The final step in the transportation forecasting process is to determine the actual street and highway routes that will be used and the number of automobiles and busses that can be expected on each highway segment. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 51 Traffic Assignment Minimum Time Path ◦ In this approach to traffic, all trips are assigned to the links that comprise the shortest time path between the two zones. ◦ This is based on the theory that a motorist or transit user will select the quickest route between any Origin- Destination Pair. ◦ To determine which route that will be, it is necessary to find the shortest route from the zone of origin to all other destination zones. ◦ The results can be depicted as a tree, referred to as a skim tree. Each zone is represented as a node in a network which represents the entire area being examined. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.625 52 Traffic Assignment Minimum Time Path ◦ Formula V T all _ ij ij ij Where: Vij = volume on link i, j Tij = travel on link i, j i,j = adjacent nodes” We will work through the following example (next slides) to illustrate the process of path building. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 53 Traffic Assignment 3 17 6 15 9 16 9 11 8 7 10 1 8 4 17 7 8 10 11 7 11 9 6 15 2 11 5 16 8 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 54 Mode Choice For the above example study area, consisting of 10 nodes, determine the shortest travel path from node 1 to all other nodes. 1 6 3 9 1 7 1 6 8 1 5 7 9 1 1 0 ◦ Solution 1 8 4 1 7 7 8 1 0 1 9 ▪ 6 7 1 1 Shortest path 1-2 = Node 1 - 2 = 11 minutes 1 1 5 2 1 5 1 8 ▪ Shortest path 1-3 = Node 1 - 3 = 16 minutes 1 6 ▪ Shortest path 1-4 = Node 1 - 2 - 4 = 17 minutes ▪ Shortest path 1-5 = Node 1 - 2 - 5 = 22 minutes ▪ Shortest path 1-6 = Node 1 – 2 – 4 - 6 = 28 minutes ▪ Shortest path 1-7 = Node 1 – 2 – 5 - 7 = 33 minutes ▪ Shortest path 1-8 = Node 1 – 2 – 5 - 8 = 38 minutes ▪ Shortest path 1-9 = Node 1 – 2 – 5 – 7 – 9 = 40 minutes ▪ Shortest path 1-10 = Node 1 – 2 – 5 – 7 – 9– 10 = 50 minutes ◦ When 2 routes have the same time, the path with the shortest travel time to the node preceding the final node is chosen. © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 55 Mode Choice 3 17 6 15 9 16 9 11 8 7 10 1 8 4 17 7 8 10 11 7 11 9 6 15 2 11 5 16 8 © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 56 Mode Choice © 2017, Southern Alberta Institute of Technology Source: Garber & Hoel, 2010, p.613 57 References Garber/Hoel. (2010). Traffic and highway engineering, (4th ed. SI version). Toronto: Cengage Learning. © 2017, Southern Alberta Institute of Technology 58 © 2017, Southern Alberta Institute of Technology. All rights reserved. This publication and materials herein are protected by applicable intellectual property laws. Unauthorized reproduction and distribution of this publication in whole or part is prohibited. For more information, contact: Director, Centre for Instructional Technology and Development Southern Alberta Institute of Technology 1301 16 Ave. N.W., Calgary, AB T2M 0L4 CIVL 353 Transportation Planning Module 3: Highway Capacity Highway Capacity © 2017, Southern Alberta Institute of Technology 2 Highway Capacity The concepts for Capacity are all detailed in this book: Written by Transportation © 2017, Southern Alberta Institute of Technology Research Board 3 Highway Capacity Source: Google Earth Pro © 2017, Southern Alberta Institute of Technology 4 Highway Capacity Source: Google Earth Pro © 2017, Southern Alberta Institute of Technology 5 Highway Capacity © 2017, Southern Alberta Institute of Technology Source: Google Earth Pro 6 Highway Capacity Source: Google Earth Pro © 2017, Southern Alberta Institute of Technology 7 Highway Capacity Source: Google Earth Pro © 2017, Southern Alberta Institute of Technology 8 Highway Capacity © 2017, Southern Alberta Institute of Technology 9 Source: Google Earth Pro Highway Capacity © 2017, Southern Alberta Institute of Technology Source: Google Earth Pro 10 Highway Capacity © 2017, Southern Alberta Institute of Technology Source: Google Earth Pro 11 Highway Capacity © 2017, Southern Alberta Institute of Technology Source: Google Earth Pro 12 Highway Capacity © 2017, Southern Alberta Institute of Technology 13 Source: https://toronto.citynews.ca/2023/03/28/401-north-america-busiest-highway/ Highway Capacity Longest Highways in the World ◦ https://blog.rentalmoose.com/longest-road-in-the-world/ Straightest Highway in the World ◦ https://www.dangerousroads.org/around-the-world/our-lists/3759-the-10-longest-straight- roads-in-the- world.html#:~:text=Highway%2010%20(Saudi%20Arabia)%3A,158%20miles)%20stretch %20of%20straightness Windiest Highways in the World ◦ http://www.theworldgeography.com/2012/03/12-of-most-winding-roads-around-world.html © 2017, Southern Alberta Institute of Technology 14 Highway Capacity Capacity is the maximum number of vehicles we can put on a road and still maintain steady flow. What is steady flow? ◦ On a Highway? ◦ On a City Street? https://www.youtube.com/watch?v=yITr127KZtQ&ab_channel=euverus https://www.youtube.com/watch?v=1ZupwFOhjl4&ab_channel=AmazingNewLife https://www.youtube.com/watch?v=UEIn8GJIg0E https://traffic-simulation.de/ © 2017, Southern Alberta Institute of Technology 15 Highway Capacity Why does traffic slow down? Traffic Snake / Shockwave https://www.youtube.com/watch?v=6ZC9h8jgSj4 https://www.youtube.com/watch?v=iHzzSao6ypE https://en.wikipedia.org/wiki/Traffic_congestion © 2017, Southern Alberta Institute of Technology 16 Highway Capacity Passenger Car unit equivalents ◦ Passenger cars, vans and pick-up trucks 1.0 ◦ Single unit trucks 1.5 ◦ Multi-unit trucks 2.5 ◦ Multi-unit tricks heavily loaded 3.0 ◦ Buses 2.0 ◦ Articulated buses or streetcars 2.5 ◦ Motorcycles 0.5 ◦ Bicycles 0.2 to 1 ◦ Pick-up trucks and vans 0.9 https://www.tac-atc.ca/sites/tac-atc.ca/files/site/doc/resources/report-capacityguide.pdf Page 3-15 © 2017, Southern Alberta Institute of Technology 17 Highway Capacity We need a way to describe how good or bad a facility is LOS ◦ Level of Service – A grading system used to describe a facility ◦ A – As good as it gets, drivers love these roads ◦ B – Reasonably good, maneuverability slightly impacted ◦ C – Stable Flow, It is not perfect, but the driver can live with it, maneuverability greatly impacted ◦ D – Approaching unstable flow, slower speeds and very little maneuverability ◦ E – Unsatisfactory drivers feel unsafe and confined by the traffic flow around them ◦ F – Failure of roadway (gridlock) to allow transport of vehicles © 2017, Southern Alberta Institute of Technology 18 Signalized Intersection Capacity LOS ◦ Level of Service – A grading system used to describe a facility ◦ A – Almost no signal phase is utilized by traffic. Very seldom does any vehicle wait longer than one signal ◦ B – An occasional signal cycle is fully utilized ◦ C – Stable flow, more frequent fully utilized signal phases, more restricted and occasionally may have to wait for more than one phase ◦ D – Increased restrictions and instability of flow. Substantial delays ◦ E – Capacity is reached, long queues of vehicles waiting for several signal cycles ◦ F – Full Saturation https://www.tac-atc.ca/sites/tac-atc.ca/files/site/doc/resources/report-capacityguide.pdf Page 4-100 © 2017, Southern Alberta Institute of Technology 19 Capacity Winter saturation is 5-20% lower Slopes of more than 2% cause issues Parking and Pedestrians Transit Stops lower capacity © 2017, Southern Alberta Institute of Technology 20 Highway Capacity LOS is based on Driver Satisfaction ◦ Engineers cannot measure driver satisfaction  Stopping a driver to ask if they are happy, makes them unhappy  May over-exaggerate a situation ◦ Engineers cannot quantify comfort, so they use criteria that are measurable These criteria are calibrated with the number of vehicles and the speed using the facility This gives an easily measurable quantity, which is ultimately used in evaluation © 2017, Southern Alberta Institute of Technology 21 Highway Capacity LOS is based on these measurable quantities: ◦ Freeway segments are judged on the density of traffic on the road ◦ Intersections (Signalized and Unsignalized) are judged on how much time you are delayed when traversing that intersection ◦ 2-Lane Highways are judged in terms of the percent of the time that drivers are forced to follow a slower-moving vehicle and the speed you are forced to drive (sometimes) © 2017, Southern Alberta Institute of Technology 22 Highway Capacity LOS A ◦ How does this Level of Service look to these 3 Groups? - Driver  - Enforcement  - Operations   Driver – Person driving the vehicle  Enforcement – Police and any agency in charge of safety on the road  Operations – Government and any agency responsible for providing and maintaining the roadway © 2017, Southern Alberta Institute of Technology 23 Highway Capacity LOS C ◦ How does this Level of Service look to these 3 Groups? - Driver  - Enforcement  - Operations   Driver – Person driving the vehicle  Enforcement – Police and any agency in charge of safety on the road  Operations – Government and any agency responsible for providing and maintaining the roadway © 2017, Southern Alberta Institute of Technology 24 Highway Capacity LOS E ◦ How does this Level of Service look to these 3 Groups? - Driver  - Enforcement  - Operations   Driver – Person driving the vehicle  Enforcement – Police and any agency in charge of safety on the road  Operations – Government and any agency responsible for providing and maintaining the roadway © 2017, Southern Alberta Institute of Technology 25 Highway Capacity LOS F ◦ How does this Level of Service look to these 3 Groups? - Driver  - Enforcement  - Operations   Driver – Person driving the vehicle  Enforcement – Police and any agency in charge of safety on the road  Operations – Government and any agency responsible for providing and maintaining the roadway © 2017, Southern Alberta Institute of Technology 26 Highway Capacity LOS Driver Enforcement Operations A  /  C    E  /  F    There is no ‘Right’ answer to ‘what is the best LOS’ each group involved has their own view. © 2017, Southern Alberta Institute of Technology 27 Highway Capacity How much flow are we designing this road for? Traffic will vary throughout the day, but we are only interested in 2 time periods. And only 1 really matters. © 2017, Southern Alberta Institute of Technology 28 Highway Capacity DHV = 836 * 4 = 3344 [What we design road for] PHF = PHV/DHV = 3255/3344 * 100% = 97.3% © 2017, Southern Alberta Institute of Technology 29 Highway Capacity AADT – Average Annual Daily Traffic ASDT – Average Summer Daily Traffic AWDT – Average Winter Daily Traffic ◦ Another way to quantify traffic volume is by counting the average traffic volume in a day Alberta Transportation Volume Counts © 2017, Southern Alberta Institute of Technology 30 Highway Capacity A Rural Alberta highway has an annual traffic volume of 5,698,300 cars. What is the daily volume? AADT = 15,611.8 veh © 2017, Southern Alberta Institute of Technology 31 Highway Capacity Trans-City highways and Recreational routes do not exhibit the peak travel we see on Urban Roads. We need a different method of establishing a design flow. Count the traffic in each hour over a year, then sort the flows from highest to lowest. Pick the nth busiest hour as your design flow. Alberta used to design to the 30th highest hour, to save money they now design to the 100th highest hour. © 2017, Southern Alberta Institute of Technology 32 Highway Capacity DHV = k x AADT DHV = Design Hour Volume In Alberta k=0.12 (100th rank hour) k=0.15 (30th rank hour) AADT = 5,698,300/365 = 15,611.8 veh DHV= 0.12(15611.8) = 1873.4 vph © 2017, Southern Alberta Institute of Technology 33 Highway Capacity If traffic remained constant, we would never need to upgrade a facility, but traffic tends to increase with population. © 2017, Southern Alberta Institute of Technology 34 Highway Capacity © 2017, Southern Alberta Institute of Technology 35 Highway Capacity © 2017, Southern Alberta Institute of Technology 36 Highway Capacity Linear Growth : Increase of “x” cars per year Compound : Increase of “x%” cars per year Until you study an area for an extended period, you do not know if the growth is Linear or Compound. Traffic = Traffic + Growth * Years = 1046 + 155 *(2005-1986) = 3991 Example 4.3: In 1986 there were: 1046 vph using a roadway. The traffic is expected to increase by: 155 vph/year. How many cars would we expect on the road in year 2005? (Assuming Linier Growth) Try Again (Round to an integer) © 2017, Southern Alberta Institute of Technology 37 Highway Capacity Compound Growth Example 4.4: In 1986 there were: 1046 vph using a roadway. The traffic is expected to increase by: 6.20% /year. How many cars would we expect on the road in year 2005? (Assuming Compound Growth) Try Again (Round to an integer) © 2017, Southern Alberta Institute of Technology 38 Highway Capacity Passenger Car Equivalence ◦ Not all vehicles on a roadway are cars. Large slow vehicles such as tractor trailer trucks take up much more of the roadway than a passenger car, however we convert all vehicles into passenger car equivalences. Design Life (Typically 20 years) The time a facility should last before it needs serious upgrades. Terrain Type ◦ Level: Trucks can Maintain Highway Speeds ◦ Rolling: Trucks slow down on hills but do not drop to low speeds ◦ Mountainous: Trucks slow down to a crawl and stay at that speed for extended periods © 2017, Southern Alberta Institute of Technology 39 2 Lane Highway What makes a 2-Lane Highway Special? ◦ Passing in Oncoming lanes IS required ◦ 80% of all roads are 2-Lane ◦ Most are used for access and capacity is not an issue ◦ Many roads this is still a consideration, Bragg Creek, Trans-Canada ◦ Need a way to quantify a good and bad road ◦ Highway Capacity Manual © 2017, Southern Alberta Institute of Technology 40 2 Lane Highway © 2017, Southern Alberta Institute of Technology 41 2 Lane Highway Level of Service is set by driver contentment ◦ Engineering Perspective  Drivers are inconsistent, and may exaggerate  Difficult to measure drivers' feelings ◦ Instead, Engineers base LOS on 2 factors;  Average Driving Speed (ATS)  Percent time spent following (3 sec headway) PTSF ◦ When drivers expect to travel at high speeds, we call that a Class I roadway © 2017, Southern Alberta Institute of Technology 42 2 Lane Highway Figure 1: LOS Criteria for 2 Lane Highways in Class I Table 1: LOS Criteria for 2 Lane Highways in Class I © 2017, Southern Alberta Institute of Technology 43 2 Lane Highway Speed is not always a required criteria for all roadways ◦ Scenic and Recreational Routes  Drivers do not expect to move at high speeds, they are more tolerant of following other vehicles, but don’t like to do so for long periods Table 2: LOS Criteria for 2 Lane Highways in Class II © 2017, Southern Alberta Institute of Technology 44 2 Lane Highway For the following highways, the Class, Average Travel Speed and percent time Following have been calculated. For each roadway determine the LOS Average % Time Spent Class LOS Travel Speed Following I 104.0 70.1 I 91.9 96.0 I 72.3 74.4 I 88.9 91.8 I 109.0 34.9 II 99.9 65.4 II 102.0 98.9 II 94.1 46.2 © 2017, Southern Alberta Institute of Technology 45 2 Lane Highway The best way to find the ATS and PTSF is to go out to the highway and measure them. But this is not always possible. © 2017, Southern Alberta Institute of Technology 46 2 Lane Highway Capacity is the maximum number of vehicles that can traverse a roadway at stable flow Capacity on a 2 Lane Highway is 3200 pc/h in both directions or 1700 pc/h in the busy direction Traffic Volumes can exceed this but flow becomes unstable Capacity is always given in passenger cars per hour, if the traffic stream is made up of other vehicle types (trucks, busses, RVs) they have to be converted to cars © 2017, Southern Alberta Institute of Technology 47 2 Lane Highway Passenger car equivalents for the following roadways are given along with the directional split. Are they LOS F? Directional VPS LOS F? (Y/N) Split 2343 75:25 2345 55:45 2842 65:35 2845 50:50 © 2017, Southern Alberta Institute of Technology 48 2 Lane Highway FFS – Speed at which the average driver who is not encumbered by other traffic will drive ◦ Factors affecting Free Flow Speed  Posted Speed  Fear of Prosecution – will make drivers stick to the posted speed (+ 10-20 km/h)  Posted speeds are usually 10-20 km/h below design speed  Enforcement – The more police there are, the more likely drivers will drive the speed limit © 2017, Southern Alberta Institute of Technology 51 2 Lane Highway Determine the Free Flow Speed (FFS) of a roadway ◦ FFS of existing roadways is done by field studies. However the method for collecting the data should be done without the driver's knowledge, and should be a different method than used by law enforcement ◦ Pavement mounted vehicle detection is the best method, or overhead video ◦ Free-flow speed is the mean speed of passenger cars measured under low to moderate flows (up to 200 pc/h) © 2017, Southern Alberta Institute of Technology 52 2 Lane Highway Estimation Guidelines ◦ Field measurements are the best way to determine FFS but they are not always possible  Designing a new roadway  Planning upgrades to an existing roadway  Planning for future traffic growth  Study does not need the level of accuracy a speed study would provide  Not enough money in budget to do a study © 2017, Southern Alberta Institute of Technology 53 2 Lane Highway Estimates of BFFS can be developed based on speed data and local knowledge of operating conditions on similar facilities. The design speed and posted speed limit of the facility may be considered in determining the BFFS; however, the design speeds and speed limits for many facilities are not based on current operating conditions © 2017, Southern Alberta Institute of Technology 55 2 Lane Highway Lane and Shoulder Width ◦ When drivers experience a road condition that makes them uncomfortable, there is a natural tendency to compensate by slowing down ◦ Driving on narrow lanes or when roadside obstructions are too close make a driver uncomfortable ◦ Ideally, all lanes will be 3.6m wide, and the shoulder 1.8m wide ◦ AT current Standards are a 3.7m wide lane, with 3.0m shoulders © 2017, Southern Alberta Institute of Technology 56 2 Lane Highway Access Points – Along a roadway, driveways and intersections will slowdown the mainstream traffic Turn movements off the highway and entering traffic accelerating up to highway speeds cause this Table 4: Adjustment (FA) for `s © 2017, Southern Alberta Institute of Technology 57 2 Lane Highway Determine Demand Flow Rate ◦ In the previous module we learned how to estimate traffic volumes, either from growth patterns or the gravity model. This volume does not take into account factors such as;  Traffic Composition (Trucks take more room than cars)  Not all roadways are level, hills slow people down The Average Travel Speed formula assumes the traffic volume is all passenger cars on level terrain. We have to convert the Design Hour Volume into Passenger Car Equivalents © 2017, Southern Alberta Institute of Technology 58 2 Lane Highway PHF – As defined in the Module Basic Principals of Highway Capacity Analysis ◦ Most 2-Lane highways located near cities will be judged using the peak hour volumes, and most highways in the rural setting will use rank hour volumes ◦ If the roadway being evaluated is a rural road, and rank hour volume was used to establish the design hour volume, use PHF = 1 © 2017, Southern Alberta Institute of Technology 60 2 Lane Highway Grade Adjustment Factor ◦ When hills are encountered the traffic stream will slowdown. This effect is more pronounced with heavy traffic, but it still happens even if the entire traffic composition is passenger vehicles Table 5: Grade Adjustment Factor (FGS) ◦ NOTE: There is a problem with this method. We need the VPS to select a value for FGS, but we need FGS to calculate VPS. © 2017, Southern Alberta Institute of Technology 61 2 Lane Highway Vehicle Composition: Ideally, we would like all of the vehicles on the road to be passenger vehicles, including cars, light trucks and motorcycles If there are trucks, busses and RV’s (Heavy Vehicles) in the traffic stream, they will decrease the maximum capacity for various reasons ◦ A truck takes up more length than a car does ◦ Trucks tend to slow down while climbing hills ◦ Typically, you will see a gap in the traffic stream in front of trucks and RV’s © 2017, Southern Alberta Institute of Technology 63 2 Lane Highway ◦ Accounting for heavy vehicles is a two-step process ◦ Convert the heavy vehicles into passenger car equivalents. That is, for each truck, we determine the number of passenger vehicles it is replacing. Table 6 Passenger Car Equivalencies for Heavy Vehicles ◦ Once the heavy traffic volume is converted into equivalent passenger vehicles, that number is converted into a single reduction to the maximum capacity. © 2017, Southern Alberta Institute of Technology 64 2 Lane Highway Adjustments to Average Travel speed caused by No Passing Zones Lack of Passing lanes reduce our ability to get past slower moving vehicles, reducing the overall speed of the roadway For passing to be allowed the sight distances must be over 300m The average percentage of no-passing zones in both directions is used for the analysis of two-way flow No-passing zones typically range from 20-50% of a rural two-lane highway. Values approaching 100% can be found on sections of winding, mountainous roads © 2017, Southern Alberta Institute of Technology 66 2 Lane Highway Table 7: Adjustment (FNP) for Effect of No passing zones on Average Travel Speed © 2017, Southern Alberta Institute of Technology 67 2 Lane Highway Check Capacity ◦ Prior to determining the level of service, we have to check the passenger car equivalents volumes to make sure the capacity of the roadway has not been exceeded ◦ We have calculated the demand flow rate two times, once for speed (EQN 3) and once for percent time following (EQN 8) ◦ If the greater of those two is over 3200 vph, then the level of service is F ◦ If the directional split is not even (50:50), the demand flow rate on the busier side of the road should not exceed 1700 vph. If it does the level of service is F © 2017, Southern Alberta Institute of Technology 76 2 Lane Highway Specific Grade ◦ The method of calculating the traffic flow is called the General Terrain Methodology because we combine the terrain into 2 broad categories of Level or Rolling ◦ If a large portion of a roadway has a specific grade for an extended length (1km or more) it is more accurate to use the Specific Grade Methodology. Each direction is evaluated separately (going up a hill will have a lower LOS then coming down) in that set of calculations ◦ This method of calculating the service flow is more accurate than the general terrain method, but it is more complicated and is not presented in this module ◦ For more information on the Specific Grade Method of calculating the service volume, look to the “Highway Capacity Manual Chapter 20” © 2017, Southern Alberta Institute of Technology 77 2 Lane Highway Some of the other treatments for a 2-Lane roadway are; ◦ Realignment of the Highway ◦ Paved shoulders over 0.6m wide ◦ 3-lane roadway with reversible center lanes ◦ Left turn bays at busy intersections ◦ Climbing and Passing lanes ◦ Turnouts ◦ Short sections of a 4-lane roadway © 2017, Southern Alberta Institute of Technology 78 Freeway / Expressway © 2017, Southern Alberta Institute of Technology 79 Freeway / Expressway © 2017, Southern Alberta Institute of Technology 80 Freeway / Expressway Freeways ◦ Not Like 2 Lane Roads because you can pass ◦ Not Like Expressways because of Intersections Expressways ◦ Free Flowing ◦ No Intersections ◦ No Stopping High Volume and High Cost © 2017, Southern Alberta Institute of Technology 81 Freeway / Expressway Freeways are typically broken up into 3 separate parts: ◦ Ramps ◦ Weave Area ◦ Basic Freeway Segments Weave Basic Freeway Ramp Area Ramp Segment © 2017, Southern Alberta Institute of Technology 82 Freeway / Expressway Ramps are the sections of the freeway where oncoming traffic enters the freeway or off- loading traffic leaves the freeway The weave area is the region where drivers are forced to change lanes to exit the highway, or are to enter into the traffic stream A basic freeway segment is a section of the freeway where influences from the ramps and weaving are minimal The design of each part is handled separately © 2017, Southern Alberta Institute of Technology 83 Freeway / Expressway Weaving KILLED the cloverleaf. Too many potential points of impact © 2017, Southern Alberta Institute of Technology 84 Freeway / Expressway How many conflict points are there? © 2017, Southern Alberta Institute of Technology 85 Freeway / Expressway Partial Cloverleaf https://en.wikipedia.org/wiki/Partial_cloverleaf_interchange#/media/File:Derry_and_407.jpg © 2017, Southern Alberta Institute of Technology 86 Freeway / Expressway Directional Interchanges - $$$$$ © 2017, Southern Alberta Institute of Technology 87 Freeway / Expressway The quest continues… © 2017, Southern Alberta Institute of Technology 88 Freeway / Expressway 140 Free Flow Dot Speed Speeds Drop 70 mph (120 km/h) 1300 Pc/hr/Ln 120 65 mph (110 km/h) Average Speed of Ideal Traffic Stream (km/h) 1450 100 60 mph (100 km/h) 55 mph (90 km/h) 1600 LOS A B C D 1750 80 E Average Travel LOS = r F Speed Level of r 𝒑 Service Flow Density 0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 Design Hour Volume (PC/hr/Ln) © 2017, Southern Alberta Institute of Technology 89 Freeway / Expressway Just like a 2-Lane Highway – Driver perspective is used to establish various Levels of Service Again, driver contentment is difficult to measure. Therefore, engineers use traffic density to measure the LOS © 2017, Southern Alberta Institute of Technology 90 Freeway / Expressway Reduction due to a mixed traffic stream ◦ Heavy Vehi

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