Author: Gary S. SpringPublisher:
ISBN:
Category : Traffic signs and signals
Languages : en
Pages : 126
Book Description
An Evaluation of Signalized Intersection Capacity Methods
Author: Gary S. SpringPublisher:
ISBN:
Category : Traffic signs and signals
Languages : en
Pages : 126
Book Description
Review and Evaluation of Methods for Analyzing Capacity at Signalized Intersections
Author: E. D. ArnoldPublisher:
ISBN:
Category : Electronic traffic controls
Languages : en
Pages : 40
Book Description
VDOT's current policy is to use and accept from others the 1994 Highway Capacity Manual (HCM) as the basis for capacity analysis on Virginia's streets and highways. VDOT uses the latest version of the Highway Capacity Software (HCS). Software programs replicating the 1994 HCM may be used by others submitting work to VDOT for review; however, all input data and assumptions must be provided, and VDOT may use the HCS to check the submitted analysis. The analysis may be rejected if different results are obtained. To recommend appropriate revisions to this policy, this study evaluated computer software other than HCS that can be used in the analysis of signalized intersections, determining which programs provide acceptable results. The study then evaluated the results from simulation models to determine when and how to use this output in the analysis of signalized intersections. The study recommended that, in addition to HCS, VDOT use and accept from others SIGNAL94 and HCM/Cinema, or TRAF/NETSIM for capacity analysis at isolated intersections. CINCH, however, should not be used or accepted. For congested, oversaturated intersections, TRAF/NETSIM should be the preferred analysis type. Estimates of queue length at isolated signalized intersections should be derived from SIGNAL94, HCM/Cinema, or TRAF/NETSIM. For non-isolated intersections where queuing and spillback are a potential problem, simulation analysis with TRAF/NETSIM should be used instead of capacity analysis to determine the operational characteristics of the corridor.
Capacity of Signalized Intersections
Author: Eugene F. ReillyPublisher:
ISBN:
Category : Roads
Languages : en
Pages : 80
Book Description
Comparative Analysis of Signalized Intersection
Author: Adolf D. MayPublisher:
ISBN:
Category : Highway capacity
Languages : en
Pages : 10
Book Description
CALSIG: an Analysis and Design Procedure for Signalized Intersections
Author: Michael James CassidyPublisher:
ISBN:
Category : CALSIG (Computer file)
Languages : en
Pages : 134
Book Description
Evaluation of Factors Affecting Signalized Intersection Capacity
Author: Clay Palmer McBrienPublisher:
ISBN:
Category : Roads
Languages : en
Pages : 280
Book Description
Signalized Intersection Capacity Data Collection
Author: Operation, Analysis, and Design of Signalized Intersections
Author: Michael KytePublisher: Createspace Independent Publishing Platform
ISBN: 9781500204365
Category : Roads
Languages : en
Pages : 0
Book Description
Before they begin their university studies, most students have experience with traffic signals, as drivers, pedestrians and bicycle riders. One of the tasks of the introductory course in transportation engineering is to portray the traffic signal control system in a way that connects with these experiences. The challenge is to reveal the system in a simple enough way to allow the student "in the door," but to include enough complexity so that this process of learning about signalized intersections is both challenging and rewarding. We have approached the process of developing this module with the following guidelines: * Focusing on the automobile user and pretimed signal operation allows the student to learn about fundamental principles of a signalized intersection, while laying the foundation for future courses that address other users (pedestrians, bicycle riders, public transit operators) and more advanced traffic control schemes such as actuated control, coordinated signal systems, and adaptive control. * Queuing models are presented as a way of learning about the fundamentals of traffic flow at a signalized intersection. A graphical approach is taken so that students can see how flow profile diagrams, cumulative vehicle diagrams, and queue accumulation polygons are powerful representations of the operation and performance of a signalized intersection. * Only those equations that students can apply with some degree of understanding are presented. For example, the uniform delay equation is developed and used as a means of representing intersection performance. However, the second and third terms of the Highway Capacity Manual delay equation are not included, as students will have no basis for understanding the foundation of these terms. * Learning objectives are clearly stated at the beginning of each section so that the student knows what is to come. At the end of each section, the learning objectives are reiterated along with a set of concepts that students should understand once they complete the work in the section. * Over 70 figures are included in the module. We believe that graphically illustrating basic concepts is an important way for students to learn, particularly for queuing model concepts and the development of the change and clearance timing intervals. * Over 50 computational problems and two field exercises are provided to give students the chance to test their understanding of the material. The sequence in which concepts are presented in this module, and the way in which more complex ideas build on the more fundamental ones, was based on our study of student learning in the introductory course. The development of each concept leads to an element in the culminating activity: the design and evaluation of a signal timing plan in section 9. For example, to complete step 1 of the design process, the student must learn about the sequencing and control of movements, presented in section 3 of this module. But to determine split times, step 6 of the design process, four concepts must be learned including flow (section 2), sequencing and control of movements (section 3), sufficiency of capacity (section 6), and cycle length and splits (section 8). Depending on the pace desired by the instructor, this material can be covered in 9 to 12 class periods.
In-service Evaluation of a Detection-control System for High-speed Signalized Intersections
Author: Karl ZimmermanPublisher:
ISBN:
Category : Electronic traffic controls
Languages : en
Pages : 52
Book Description
Traffic engineers are often faced with operational and safety challenges at rural, high-speed signalized intersections. Vehicle-actuated control, combined with multiple advance detectors, is often used to improve operations and safety. However, this type of detection and control has not always resulted in a significant number of crashes. Crashes sometimes continue to occur at high-speed intersections, and delays to traffic movements can be unnecessarily long. An innovative detection-control system was developed for the Texas Department of Transportation to minimize both delay and crash frequency at rural intersections. This system was subsequently implemented at several intersections in Texas and its safety and operational benefits were evaluated. This report documents the findings and conclusions reached as a result of a three-year implementation project. The Detection-Control System was installed at each of eight intersections in Texas during the three-year period. Five of the intersections were suitable for a before-after study of safety and operational data. An evaluation of the before-after data indicated that the Detection-Control System was able to reduce delay by 14 percent, stop frequency by 9 percent, red-light violations by 58 percent, heavy-vehicle red-light violations by 80 percent, and severe crash frequency by 39 percent.
Traffic Operations at Intersections
Author: Rod TroutbeckPublisher:
ISBN:
Category :
Languages : en
Pages : 250
Book Description
Traffic Operations at Intersections: Learning and Applying the Models and Methods of the Highway Capacity Manual Chapters on all-way stop-controlled intersections, two-way stop-controlled intersections, and signalized intersections Designed for practicing transportation engineers and university seniors and graduate students 11 simplified scenarios to open-up your understanding of the HCM 43 example calculations that are fully worked out and explained in detail 7 computational engines that allow you to see inside and then apply the models 138 figures to clearly illustrate concepts Additional problems online The models of the Highway Capacity Manual (HCM) are often the engineer's choice to analyze intersection performance. These models are complex, and nearly all transportation engineers use software implementations of these models to conduct their analyses. Software applications are powerful tools that help engineers solve problems. But these applications also serve as barriers to the understanding of the complex models embedded in the software. Our major objective in writing this book is to transform the "black box" of the HCM intersection models, and their software implementations, into a "clear box" that allows the engineer to better understand how these models work. We do this through the idea of the "simplified scenario." The eleven scenarios that we present are based on conditions greatly simplified from what you would normally see in the field. By focusing on one concept at a time, in the context of these simplified conditions, you will better understand the fundamentals of the HCM intersection models. You will then be able to apply these models to more complex intersections with skill, confidence, and insight.