Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Study On Left Turn Safety And Gap Acceptance At Unsignalized Intersections PDF full book. Access full book title Study On Left Turn Safety And Gap Acceptance At Unsignalized Intersections.
| Author | : Hongmei Zhou |
| Publisher | : |
| Total Pages | : 206 |
| Release | : 2009 |
| Genre | : |
| ISBN | : |
| Author | : |
| Publisher | : |
| Total Pages | : 80 |
| Release | : 2004 |
| Genre | : Left-turn lanes |
| ISBN | : |
It is generally accepted that the level of service (LOS) at intersections significantly affects the overall LOS of the road system. It is also known that the LOS at an intersection can be adversely affected by frequently allowing left-turning vehicles to block through traffic. In addition, crash rates tend to be higher at intersections than on through sections of a road. The separation of left-turning vehicles from through traffic is therefore an important condition for the safe and effective operation of intersections. Existing guidelines for installing left-turn lanes have several limitations. They are mainly based on the traffic volumes at the intersection, and they use deterministic models with fixed gap acceptance and/or left-turn maneuver times. In addition, the guidelines for left-turn lanes for unsignalized intersections and signalized intersections must be specific for the type of intersection. In this study, new left-turn guidelines for both unsignalized and signalized intersections were developed on the basis of well-validated event-based simulation programs. Guidelines for unsignalized intersections were based on the percentage of left turns blocking through vehicles, whereas the guidelines for signalized intersections were developed using a minimum left-turn volume of either 85% left-turn capacity or LOS E delay (55 seconds/vehicle). In addition to the general guidelines, a prioritization tool that can be used to prioritize candidate intersections was developed. The prioritization tool accounts for both operational and safety aspects.
| Author | : Kay Fitzpatrick |
| Publisher | : Transportation Research Board |
| Total Pages | : 62 |
| Release | : 2013 |
| Genre | : Left-turn lanes |
| ISBN | : 0309258987 |
"TRB's National Cooperative Highway Research Program (NCHRP) Report 745: Left-Turn Accommodations at Unsignalized Intersections presents guidance for the selection and design of left-turn accommodations at unsignalized intersections. The report includes 11 case studies of typical situations that illustrate the use of the guidance." -- publisher's description.
| Author | : ITE (Institute of Transportation Engineers) |
| Publisher | : John Wiley & Sons |
| Total Pages | : 688 |
| Release | : 2016-01-26 |
| Genre | : Technology & Engineering |
| ISBN | : 1118762304 |
Get a complete look into modern traffic engineering solutions Traffic Engineering Handbook, Seventh Edition is a newly revised text that builds upon the reputation as the go-to source of essential traffic engineering solutions that this book has maintained for the past 70 years. The updated content reflects changes in key industry standards, and shines a spotlight on the needs of all users, the design of context-sensitive roadways, and the development of more sustainable transportation solutions. Additionally, this resource features a new organizational structure that promotes a more functionally-driven, multimodal approach to planning, designing, and implementing transportation solutions. A branch of civil engineering, traffic engineering concerns the safe and efficient movement of people and goods along roadways. Traffic flow, road geometry, sidewalks, crosswalks, cycle facilities, shared lane markings, traffic signs, traffic lights, and more—all of these elements must be considered when designing public and private sector transportation solutions. Explore the fundamental concepts of traffic engineering as they relate to operation, design, and management Access updated content that reflects changes in key industry-leading resources, such as the Highway Capacity Manual (HCM), Manual on Uniform Traffic Control Devices (MUTCD), AASSHTO Policy on Geometric Design, Highway Safety Manual (HSM), and Americans with Disabilities Act Understand the current state of the traffic engineering field Leverage revised information that homes in on the key topics most relevant to traffic engineering in today's world, such as context-sensitive roadways and sustainable transportation solutions Traffic Engineering Handbook, Seventh Edition is an essential text for public and private sector transportation practitioners, transportation decision makers, public officials, and even upper-level undergraduate and graduate students who are studying transportation engineering.
| Author | : L. K. Staplin |
| Publisher | : |
| Total Pages | : 96 |
| Release | : 2001 |
| Genre | : |
| ISBN | : |
| Author | : C. N. Kloeden |
| Publisher | : |
| Total Pages | : 54 |
| Release | : 2001 |
| Genre | : Automobiles |
| ISBN | : |
| Author | : Sahar Nabaee |
| Publisher | : |
| Total Pages | : 71 |
| Release | : 2011 |
| Genre | : |
| ISBN | : |
Gap acceptance behavior is critical to the safety and operational performance of unsignalized intersections. The complex nature of the human behavior and its dependence on various socioeconomic and environmental parameters makes it challenging for transportation professionals to assess the performance of such intersections. To investigate the behavioral patterns of drivers at unsignalized intersections, a novel procedure was developed and validated for the accurate observation of naturalistic gap acceptance behavior. Specifically, the authors examined two-way stop-controlled (TWSC) intersections with a two way left turn lane (TWLTL) on the major road. After examining the critical gap and identifying behavioral changes caused by waiting time, time of day, presence of passengers, and presence of queue, the authors further investigated the relationship between waiting time and gap acceptance and analyzed the variations in waiting time for right and left turn maneuvers. The results of this study reinforce the notion that driver behavior is affected by external factors such as waiting time, time of day, presence of passengers, presence of queue, etc. and should continue to be investigated in localities across the country.
| Author | : Douglas W. Harwood |
| Publisher | : |
| Total Pages | : 204 |
| Release | : 2002 |
| Genre | : Roads |
| ISBN | : |
This report presents the results of research that performed a well-designed before-after evaluation of the safety effects of providing left- and right-turn lanes for at-grade intersections. Geometric design, traffic control, traffic volume, and traffic accident data were gathered for a total of 280 improved intersections, as well as 300 similar intersections that were not improved during the study period. The types of improvement projects evaluated included installation of added left-turn lanes, added right-turn lanes, and extension of the length of existing left- or right-turn lanes. An observational before-after evaluation of these projects was performed using several alternative evaluation approaches. The three contrasting approaches to before-after evaluation used were the yoked comparison or matched-pair approach, the comparison group approach, and the Empirical Bayes approach. The research not only evaluated the safety effectiveness of left- and right-turn lane improvements, but also compared the performance of these three alternative approaches in making such evaluations. The research developed quantitative safety effectiveness measures for installation design improvements involving added left-turn lanes and added right-turn lanes. The research concluded that the Empirical Bayes method provided the most accurate and reliable results. Further use of this method is recommended.
| Author | : Lee August Rodegerdts |
| Publisher | : Transportation Research Board |
| Total Pages | : 407 |
| Release | : 2010 |
| Genre | : Technology & Engineering |
| ISBN | : 0309155118 |
TRB's National Cooperative Highway Research Program (NCHRP) Report 672: Roundabouts: An Informational Guide - Second Edition explores the planning, design, construction, maintenance, and operation of roundabouts. The report also addresses issues that may be useful in helping to explain the trade-offs associated with roundabouts. This report updates the U.S. Federal Highway Administration's Roundabouts: An Informational Guide, based on experience gained in the United States since that guide was published in 2000.
| Author | : Marco Guerrieri |
| Publisher | : Springer Nature |
| Total Pages | : 196 |
| Release | : 2020-12-14 |
| Genre | : Technology & Engineering |
| ISBN | : 3030607232 |
This book covers a selection of fundamental topics of traffic engineering useful for highways facilities design and control. The treatment is concise but it does not neglect to examine the most recent and crucial theoretical aspects which are at the root of numerous highway engineering applications, like, for instance, the essential aspects of highways traffic stream reliability calculation and automated highway systems control. In order to make these topics easy to follow, several illustrative worked examples of applications are provided in great detail. An intuitive and discursive, rather than formal, style has been adopted throughout the contents. As such, the book offers up-to-date and practical knowledge on several aspects of traffic engineering, which is of interest to a wide audience including students, researchers as well as transportation planners, public transport specialists, city planners and decision-makers.
