Determination and Utilization of Dilemma Zone Length and Location for Safety Assessment of Rural High-Speed Signalized Intersections

2020 ◽  
Vol 2674 (4) ◽  
pp. 272-280
Author(s):  
Min-Wook Kang ◽  
Moynur Rahman ◽  
Joyoung Lee
Keyword(s):  
High Speed ◽  
Red Light ◽  
Signalized Intersections ◽  
Percentage Error ◽  
Traffic Operations ◽  
Safety Level ◽  
Zone Length ◽  
Dilemma Zone ◽  
Intersection Safety ◽  
Traffic Conflicts

The objective of the present study is to see how the dilemma zone length and location are related to intersection safety at rural high-speed signalized intersections. For that, dilemma zones at 30 rural signalized intersection approaches where similar traffic operations and land-use conditions are present were identified, and traffic conflicts associated with the dilemma zones were investigated. Drivers’ stop or go behaviors as well as vehicle dynamics (e.g., vehicle speeds and locations) during the yellow and red clearance intervals were collected and analyzed to determine the dilemma zone length and location of each site. Red-light running violations and vehicles’ abrupt stops were also collected to investigate the relationship between such conflicts and dilemma zone length and location. As a result, two dilemma zone conflict models were developed. The analysis results show that the conflict models are accurate enough to predict the safety level of high-speed signalized intersections using the two dilemma zone variables. Results show that the chance of intersection angle conflicts increases if the dilemma zone is located farther from the intersection stop bar. Results also show that there would be a high chance of rear-end conflicts if the dilemma zone length is longer. The models were validated with additional datasets, and acceptable root means square error and mean absolute percentage error values were obtained as a result.

Performance of Advance Warning for End of Green System for High-Speed Signalized Intersections

2005 ◽  
Vol 1925 (1) ◽  
pp. 176-184 ◽  
Author(s):  
Srinivasa R. Sunkari ◽  
Carroll J. Messer ◽  
Hassan Charara
Keyword(s):  
High Speed ◽  
Red Light ◽  
Signalized Intersections ◽  
Traffic Signal ◽  
Traffic Operations ◽  
Dilemma Zone ◽  
Green Approach ◽  
High Speeds ◽  
Approach Speed ◽  
Green System

A major difficulty with traffic signal operation on high-speed approaches is the dilemma faced by approaching motorists when the downstream signal turns yellow. Should the motorists stop or proceed through the intersection? Crashes that may occur at these intersections result in excessive property damage and personal injury because of the high speeds involved. The Texas Transportation Institute has developed a new system named the Advance Warning for End of Green System (AWEGS) for application at high-speed signalized intersections. Typically, dilemma zone detection strategy is based on a certain approach speed (typically the 85th percentile). AWEGS provides protection for the majority of motorists who are not covered by the dilemma zone treatment. AWEGS provides advance warning to motorists by using signs mounted on the roadside. These signs (Be Prepared To Stop When Flashing) would flash a beacon about 5 to 6 s before the onset of the yellow signal for high-speed approaches. Similar systems have been implemented in Canada and in a few U.S. states that use the trailing-green approach, which results in loss of dilemma zone protection every cycle. AWEGS, however, is almost completely independent of the traffic signal controller, and hence the signal controller would continue to provide the dilemma zone protection for which it was designed. The system was implemented at two sites in Waco and Brenham, Texas. Results of AWEGS implementation illustrated an improvement in traffic operations. AWEGS consistently enhanced the dilemma zone protection at intersections and reduced red light running by about 40%.

scholarly journals Modeling and Application of Pedestrian Safety Conflict Index at Signalized Intersections

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Wei Cheng ◽  
Ning Zhang ◽  
Wei Li ◽  
Jianfeng Xi
Keyword(s):  
Safety Evaluation ◽  
Pedestrian Safety ◽  
Evaluation Study ◽  
Signalized Intersections ◽  
Safety Level ◽  
Intersection Safety ◽  
Road Users ◽  
Traffic Conflict ◽  
Vulnerable Road Users ◽  
The City

Traffic conflict between turning vehicles and pedestrians is the leading cause of pedestrian fatalities at signalized intersections. In order to provide a solution for evaluating intersection safety for vulnerable road users, this paper first determines the most important factors in analyzing pedestrian-vehicle conflict and puts forward a pedestrian safety conflict index (SCI) model to establish a quantitative standard for safety evaluation of two- or multiphase intersections. A safety level system is then designed based on SCI to help categorize and describe the safety condition of intersections applicable to the model. Finally, the SCI model is applied to the evaluation of two intersections in the city of Changchun, the result of which complies with expectation, indicating the model’s potential in providing an improved approach for pedestrian-vehicle conflict evaluation study.

scholarly journals Using Cellular Automata to Investigate Pedestrian Conflicts with Vehicles in Crosswalk at Signalized Intersection

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Xiaomeng Li ◽  
Xuedong Yan ◽  
Xingang Li ◽  
Jiangfeng Wang
Keyword(s):  
Cellular Automata ◽  
Signalized Intersections ◽  
Influential Factors ◽  
Urban Traffic ◽  
Signalized Intersection ◽  
Signal Timing ◽  
Cellular Automata Model ◽  
Intersection Safety ◽  
Traffic Conflicts ◽  
Simulation Results

The operational efficiency and safety of pedestrian flows at intersections is an important aspect of urban traffic. Particularly, conflicts between pedestrians and vehicles in crosswalk are one of the most influential factors for intersection safety. This paper presents a cellular automata model that simulates pedestrian and vehicle crossing behaviors at signalized intersections. Through the simulation, we investigate the effects of different pedestrian signal timing and crosswalk widths on the crosswalk capacity, the number of traffic conflicts between pedestrians and vehicles, and pedestrian delay due to the conflicts. The simulation results indicate that the cellular automata is an effective simulation platform for investigating complex pedestrian-related traffic phenomenon at signalized intersections.

Fuzzy sets to describe driver behavior in the dilemma zone of high-speed signalized intersections

2012 ◽  
Vol 15 (2) ◽  
pp. 132-143 ◽  
Author(s):  
David S. Hurwitz ◽  
Haizhong Wang ◽  
Michael A. Knodler ◽  
Daiheng Ni ◽  
Derek Moore
Keyword(s):  
Fuzzy Sets ◽  
High Speed ◽  
Driver Behavior ◽  
Signalized Intersections ◽  
Dilemma Zone

scholarly journals Investigating Different Types of Red-Light Running Behaviors among Urban e-Bike Rider Mixed Groups

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Fan Zhang ◽  
Chenchen Kuai ◽  
Huitao Lv ◽  
Wenhao Li
Keyword(s):  
Traffic Safety ◽  
Traffic Accidents ◽  
Unobserved Heterogeneity ◽  
Red Light ◽  
Multinomial Logit Model ◽  
Time Of Day ◽  
Signalized Intersections ◽  
Traffic Light ◽  
Safety Level ◽  
Red Light Running

The red-light running (RLR) behaviors of urban mixed e-bike groups (delivery and ordinary e-bike) have become the main cause of traffic accidents at signalized intersections. The primary purpose of this study is to identify influencing factors of e-bike riders’ RLR behaviors, focusing on the role of delivery e-bike riders in mixed e-bike rider groups. Crossing behaviors of 4,180 e-bike samples (2006 delivery e-bikes and 2174 ordinary e-bikes) at signalized intersections are observed in Xi’an, China. The random parameter multinomial logit model is employed to capture the unobserved heterogeneous effects, and the effects of interaction terms are also considered. The results indicate that delivery e-bike riders are more likely to run red lights than ordinary e-bike riders. E-bike type, riders’ age, waiting position, traffic volume, traffic light type, and time of day are associated with crossing behaviors in urban mixed e-bike groups. In addition, the variable of traffic light status is found to account for unobserved heterogeneity. Findings are indicative to the development of effective implications in improving e-bikes’ traffic safety level at signalized intersections.

System Integration and Field Tests for Developing In-Vehicle Dilemma Zone Warning System

2003 ◽  
Vol 1826 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Young-Jun Moon ◽  
Jooil Lee ◽  
Yukyung Park
Keyword(s):  
System Integration ◽  
Red Light ◽  
Field Tests ◽  
Warning System ◽  
Field Testing ◽  
Signalized Intersections ◽  
Dilemma Zone ◽  
Stopping Distance ◽  
Real Traffic ◽  
Warning Device

The basis for system integration and field testing was developed for assessing a dilemma zone warning system for signalized intersections. The system consists of hardware (an in-vehicle warning device, roadside antenna, and traffic signal controller) and software to operate and test the integrated component warning and communications systems. Field tests were conducted in real traffic situations to test the system’s warning initiation time from the signal controller, the activation and duration of the visual and audible signals, and the warning delay, on the basis of relationships between distance variables that include the safe stopping distance and the location of roadside antenna. Findings from the field tests at two signalized intersections indicated that the system could be implemented at signalized intersections to eliminate the dilemma zone, relative to approach speeds, and to reduce red-light violations and intersection collisions by means of an in-vehicle warning device.

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