Effects of major-road vehicle speed and driver age and gender on left-turn gap acceptance

This paper attempts to identify factors that may influence the gap acceptance behavior of drivers who turn left from the major road at unsignalized intersections. Drivers’ accepted and rejected gaps as well as their age and gender were collected at six unsignalized intersections with both two and four lanes on the major road, with and without the presence of a Left-Turn Lane (LTL), and with both high and low Speed Limits (SLs). Whether or not a driver accepts a given gap was considered as a binary decision and correlated logit models were used to estimate the probability of accepting a gap. Models with different factors were tested and the best model was selected by the quasi-likelihood information criterion. The gap duration, the number of rejected gaps, the mean and total time interval of the rejected gaps and the gender of the driver were all significant in explaining the variation of the gap acceptance probability, whereas the number of lanes of the major road, the presence of LTL, the SL and the driver’s age category were not. Gap acceptance probability functions were determined based on the best model, including both the factors of the number of rejected gaps and the mean time interval of the rejected gaps. As the values of these two factors increase, the probability of accepting a given gap rises up. The developed model can be further applied in practice to improve the analysis of traffic operations and capacity at unsignalized intersections.

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Sight Distance for Stop-Controlled Intersections Based on Gap Acceptance

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1701-05 ◽

2000 ◽

Vol 1701 (1) ◽

pp. 32-41 ◽

Cited By ~ 6

Author(s):

Douglas W. Harwood ◽

John M. Mason ◽

Robert E. Brydia

Keyword(s):

Travel Time ◽

Field Studies ◽

Major Road ◽

Gap Acceptance ◽

Road Vehicle ◽

Sight Distance ◽

Minor Road ◽

Distance Model ◽

Design Speed ◽

A Minor

The current AASHTO policy for sight distance at Stop-controlled intersections is based on a model of the acceleration performance of a minor-road vehicle turning left or right onto a major road and the deceleration performance of the following major road vehicle. An alternative intersection sight distance model based on gap acceptance is developed and quantified. Field studies that were performed to determine the critical gaps appropriate for use in sight distance design are described. It is recommended that the sight distance along the major road for a passenger car at a Stop-controlled intersection should be based on a distance equal to 7.5 s of travel time at the design speed of the major road. Longer sight distances are recommended for minor-road approaches that have sufficient truck volumes to warrant consideration of a truck as the design vehicle.

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Evaluation of dynamic passing gap acceptance on two-lane highways using field data

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2016-0572 ◽

2017 ◽

Vol 44 (11) ◽

pp. 871-880 ◽

Cited By ~ 6

Author(s):

Udai Hassein ◽

Maksym Diachuk ◽

Said Easa

Keyword(s):

Regression Models ◽

Field Data ◽

Field Studies ◽

Gap Acceptance ◽

Data Logger ◽

Driver Behaviour ◽

Age And Gender ◽

Time To Collision ◽

And Gender ◽

Acceptance Model

Gap availability is an important element of safe passing on two-lane highways. Time gaps are used to determine passing behaviour based on human factors. In this paper, the decision whether to accept or reject an available passing gap is modelled using logistic regression technique that included driver characteristics (age and experience) and the gap size. Field studies were conducted to collect experimental data regarding passing driver behaviour. The data were collected using dual camera Car DVRs and a GPS data logger device that records the instantaneous speed and position of the three vehicles involved in the passing maneuver: passing vehicle, impeding vehicle, and opposing vehicle. Regression models that include driver age and gender (required as input to the gap acceptance model) were established for initial passing time, starting gap, ending gap, and time to collision. The gap acceptance model was implemented in Simulink and the results revealed that driver characteristics significantly affect gap acceptance decisions.

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Delays to road traffic at an intersection

Journal of Applied Probability ◽

10.2307/3211861 ◽

1964 ◽

Vol 1 (2) ◽

pp. 297-310 ◽

Cited By ~ 20

Author(s):

G. F. Yeo ◽

B. Weesakul

Keyword(s):

Road Traffic ◽

Partial Solution ◽

Major Road ◽

Gap Acceptance ◽

Road Vehicle ◽

Mean Delay ◽

Minor Road ◽

The Mean ◽

Stationary Waiting Time ◽

A Minor

A model for road traffic delays at intersections is considered where vehicles arriving, possibly in bunches, in a Poisson process in a one way minor road yield right of way to traffic, which forms alternate bunches and gaps, in a major road. The gap acceptance times are random variables, and depend on whether or not a minor road vehicle is immediately following another minor road vehicle into the intersection or not.The transforms of the stationary waiting time and queue size distributions, and the mean stationary delay, for minor road vehicles are obtained by substitution of determined service time distributions into results for a generalisation of the M/G/1 queueing system. Some numerical results are given to illustrate the increase in the mean delay for variable gap acceptance times for a Borel-Tanner distribution of major road traffic, and a partial solution is given for a two way major road.

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Effect of Offset between Opposing Left-Turn Lanes on Driver Performance

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198196152300108 ◽

1996 ◽

Vol 1523 (1) ◽

pp. 61-72 ◽

Cited By ~ 3

Author(s):

Mohammed S. Tarawneh ◽

Patrick T. Mccoy

Keyword(s):

Age Groups ◽

Older Drivers ◽

Age And Gender ◽

Left Turn ◽

Sight Distance ◽

Driver Performance ◽

Driving Conditions ◽

Left Turns ◽

And Gender

The objective of the research described here was to study the effects of the offset between opposing left-turn lanes on the turning performance of drivers with respect to driver age and gender. Left-turn performance of 100 subjects within three age groups (25–45, 65–74, and 75+ years old) was evaluated under normal driving conditions at four intersections of different left-turn offset configurations. The results indicate that driver performance can be adversely affected by offsets that are much less (i.e., more negative) than the negative 0.9-m offset. Such large negative offsets significantly increase the size of the critical gaps of drivers turning left and also seem to increase the likelihood of conflicts between left turns and opposing through traffic. Large negative offsets may be particularly troublesome for older drivers and women drivers, who are less likely to position their vehicles within the intersection to see beyond vehicles in the opposing left-turn lane. Surprisingly, driver perceptions of the level of comfort and degree of difficulty were not found to improve with the increased sight distance provided by larger (i.e., more positive) offsets. The 1.8-m positive offset was associated with a lower level of comfort and a higher degree of difficulty perceived by drivers making left turns than the 0.9-m negative offset, which provided less sight distance. This may have been because the 0.9-m negative offset is much more common than the 1.8-m positive offset.

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Delays to road traffic at an intersection

Journal of Applied Probability ◽

10.1017/s0021900200108411 ◽

1964 ◽

Vol 1 (02) ◽

pp. 297-310 ◽

Cited By ~ 3

Author(s):

G. F. Yeo ◽

B. Weesakul

Keyword(s):

Road Traffic ◽

Partial Solution ◽

Major Road ◽

Gap Acceptance ◽

Road Vehicle ◽

Mean Delay ◽

Minor Road ◽

The Mean ◽

Stationary Waiting Time ◽

A Minor

A model for road traffic delays at intersections is considered where vehicles arriving, possibly in bunches, in a Poisson process in a one way minor road yield right of way to traffic, which forms alternate bunches and gaps, in a major road. The gap acceptance times are random variables, and depend on whether or not a minor road vehicle is immediately following another minor road vehicle into the intersection or not. The transforms of the stationary waiting time and queue size distributions, and the mean stationary delay, for minor road vehicles are obtained by substitution of determined service time distributions into results for a generalisation of the M/G/1 queueing system. Some numerical results are given to illustrate the increase in the mean delay for variable gap acceptance times for a Borel-Tanner distribution of major road traffic, and a partial solution is given for a two way major road.

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