Analysis of Sight Distance, Crash Rate, and Operating Speed Relationships for Low-Volume Single-Lane Roundabouts in the United States

Zirkel, Brian; Park, Sehhoon; McFadden, John; Angelastro, Michael; McCarthy, Leslie Myers

doi:10.1061/(asce)te.1943-5436.0000532

Cited by 17 publications

(12 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Fitzpatrick et al [15] analyzed the rationality of the basic assumptions for vehicle deceleration in the merging areas and the applicability of the deceleration rate in current design standards in U.S. Taking roundabouts as the research object, Zirkel et al [16] discussed the effect of 85 th percentile speed distribution and sight distance of the drivers on crash rates for lowvolume single-lane roundabouts. Perco et al [17] established an operating speed model for the merging area and diverging area of two types of interchanges by using the data obtained from radar guns.…”

Section: Helix Ramps Helix Brodgesmentioning

confidence: 99%

Speed Behavior of Passenger Car on Helical Ramps and Helical Bridges in Mountain Riverside City

Jin

Liu

et al. 2018

Journal of Advanced Transportation

View full text Add to dashboard Cite

Helix alignment can allow for a rapid change in road elevation in size-constrained spaces, and it is becoming increasingly popular in interchange design throughout the world. However, driving patterns and vehicle operating characteristics have not been clearly defined on helical ramps. This work conducted field driving tests on four helical ramps located in Chongqing, China. The trajectory, speed, and acceleration of vehicles under normal driving conditions were collected. Thus speed characteristics and speed patterns on helical ramps, as well as their affecting factors, were obtained and analyzed. The findings in this study can provide basic data referencing for designers and engineers, to help them understand how a multilayered helical ramp works, thus to essentially improve the safety level of helix ramps. Moreover, our findings allow bridge designers to understand whether the actual vehicle operating conditions acted in accordance with their expected design requirements, i.e., whether the expected design requirements are achieved.

show abstract

Section: Helix Ramps Helix Brodgesmentioning

confidence: 99%

Speed Behavior of Passenger Car on Helical Ramps and Helical Bridges in Mountain Riverside City

Jin

Liu

et al. 2018

Journal of Advanced Transportation

View full text Add to dashboard Cite

show abstract

“…Each method, when formulated, has to consider some aspects of roundabout circulation in comparison to others (geometric elements, vehicular flow, and user behavior) (Vaiana et al 2013). Zirkel et al (2013) explores the relationship between sight distance parameters, crash rates, and operating speeds at low-volume single-lane roundabouts in the United States. The understanding of the interaction of design, operations, and crash performance is a step forward in the development and application of performance-based standards for roundabouts.…”

Section: Research On the Operation Of Roundabouts Basedmentioning

confidence: 99%

“…The understanding of the interaction of design, operations, and crash performance is a step forward in the development and application of performance-based standards for roundabouts. The specific objective of this paper (Zirkel et al 2013) is to quantify the relationship between crash rates, sight distance parameters, and operating speeds to present an approach to establishing performance-based standards that highway practitioners could adopt in roundabout design.…”

Section: Research On the Operation Of Roundabouts Basedmentioning

confidence: 99%

Research on the operation of roundabouts based on the sustainable development principles

Sivilevičius

Paliulis

Klibavičius

et al. 2015

The Baltic Journal of Road and Bridge Engineering

View full text Add to dashboard Cite

The main elements of urban transport infrastructure include: the street network with intersections, bridges, viaducts, flyovers, vehicular traffic tunnels. Unsignalized four-leg intersections and roundabouts is the largest “saturated transport flow” of the street network. Roundabouts which were designed as far back as 1970–1980 were well-functioning when the car ownership level was 180–200 veh/1000 inhabitants. Currently, when the level of car ownership comes to 520–560 veh/1000 inhabitants, unsignalized roundabouts operate in the “oversaturated flows” regime. The research results of the Vilnius Gediminas Technical University and other universities showed that when designing new or reconstructing existing intersections the indicators of territorial planning, transport planning, environmental protection, traffic safety should be considered. As a common indicator for assessing all other indicators a monetization (estimation in monetary terms) should be used. When preparing projects for intersection reconstruction it is recommended to apply a new method of intersection analysis and evaluation based on the principles of sustainable development of urban transport infrastructure.

show abstract

“…Driving speed serves as the most representative variable due to a clear correlation between drivers' perception of the road and behavior change [13][14][15][16]. Meanwhile, studies which adopted sight distance as the input of the speed prediction model found that the index is highly correlated to driver's operating speed, as well as driving safety [17][18][19].…”

Section: Introductionmentioning

confidence: 99%

Speed Distribution Prediction of Freight Vehicles on Mountainous Freeway Using Deep Learning Methods

Chen

2020

Journal of Advanced Transportation

View full text Add to dashboard Cite

Driving speed is one of the most critical indicators in safety evaluation and network monitoring in freight transportation. Speed prediction model serves as the most efficient method to obtain the data of driving speed. Current speed prediction models mostly focus on operating speed, which is hard to reveal the overall condition of driving speed on the road section. Meanwhile, the models were mostly developed based on the regression method, which is inconsistent with natural driving process. Recurrent neural network (RNN) is a distinctive type of deep learning method to capture the temporary dependency in behavioral research. The aim of this paper is to apply the deep learning method to predict the general condition of driving speed in consideration of the road geometry and the temporal evolutions. 3D mobile mapping was applied to obtain road geometry information with high precision, and driving simulation experiment was then conducted with the help of the road geometry data. Driving speed was characterized by the bimodal Gauss mixture model. RNN and its variants including long short-term memory (LSTM) and RNN and gated recurrent units (GRUs) were utilized to predict speed distribution in a spatial-temporal dimension with KL divergence being the loss function. The result proved the applicability of the model in speed distribution prediction of freight vehicles, while LSTM holds the best performance with the length of input sequence being 400 m. The result can be related to the threshold of drivers’ information processing on mountainous freeway. Multiple linear regression models were constructed to be a contrast with the LSTM model, and the results showed that LSTM was superior to regression models in terms of the model accuracy and interpretability of the driving process and the formation of vehicle speed. This study may help to understand speed change behavior of freight vehicles on mountainous freeways, while providing the feasible method for safety evaluation or network efficiency analysis.

show abstract

Analysis of Sight Distance, Crash Rate, and Operating Speed Relationships for Low-Volume Single-Lane Roundabouts in the United States

Cited by 17 publications

References 2 publications

Speed Behavior of Passenger Car on Helical Ramps and Helical Bridges in Mountain Riverside City

Speed Behavior of Passenger Car on Helical Ramps and Helical Bridges in Mountain Riverside City

Research on the operation of roundabouts based on the sustainable development principles

Speed Distribution Prediction of Freight Vehicles on Mountainous Freeway Using Deep Learning Methods

Contact Info

Product

Resources

About