Analysing truck harsh braking incidents to study roundabout accident risk

Abstract

In order to reduce accident risk, highway authorities prioritise maintenance budgets partly based upon previous accident history. However, as accident rates have continued to fall, this approach has become problematic as accident 'black spots' have been treated and the number of accidents at any individual site has fallen, making previous accident history a less reliable indicator of future accident risk. Another way of identifying sites of higher accident risk might be to identify near-miss accidents (where an accident nearly happened but was avoided). The principal aim of this paper is to analyze potentially unsafe truck driving conditions from counts of Harsh Braking Incidents (HBIs) at roundabouts and compare the results to similar, previous studies of accident numbers at the same sites, to explore if HBIs can be studied as a surrogate for accidents. This is achieved by processing truck telematics data with geo-referenced incidents of harsh braking. Models are then developed to characterise the relationships between truck HBIs and geometric and traffic variables. These HBIs are likely to occur more often than accidents and may, therefore, be useful in identifying sites with high accident risk. Based on the results of this study, it can be concluded that HBIs are influenced by traffic and geometric variables in a similar way to accidents; therefore they may be useful in considering accident risk at roundabouts. They are a source of higher volumes of data than accidents, which is important in considering changes or trends in accident risk over time. The results showed that random-parameters count data models provide better goodness of fit compared to fixed-parameters models and more variables were found to be significant, giving a better prediction of events.

A Simulation Study of Passing Drivers' Responses to the Automated Truck-Mounted Attenuator System in Road Maintenance

“…In this study, fps is 60, and α h = 10.648 mph/s chosen according to [16]. The number of brakes and harsh brakes can be counted respectively using {B j }.…”

Quantifying the effect of roadway, driver, vehicle, and location characteristics on the frequency of longitudinal and lateral accelerations

“…There is consensus that driving within the acceleration values of ±0.05g is considered steady state driving (Ozaki 1993;Ali et al 2019). However, various studies have used different thresholds for classifying harsh acceleration events (Kamla, Parry, and Dawson 2019). A threshold of around 0.5g has often been used in transportation studies to classify harsh braking and lateral accelerations events.…”

“…The positive correlation between crash and harsh acceleration rates has been shown for both longitudinal as well as lateral acceleration events (Simons-Morton et al 2012). However, when trying to explore these correlations, varied acceleration thresholds have been used to define harsh acceleration events and a consistent methodology does not exist (Kamla, Parry, and Dawson 2019). Moreover, most studies analyzing harsh acceleration events do not simultaneously control for the various factors that could be affecting driver acceleration behavior such as roadway properties, driver demographics, vehicle characteristics, and environmental features.…”

Correlating Hard-Braking Activity with Crash Occurrences on Interstate Construction Projects in Indiana

“…Using simulated driving environments, hard-braking by distracted motorists was found to have significant impacts on following vehicles in traffic, increasing the risk of a rear-end collision (Haque and Washington 2015). Investigations into the use of harsh braking incidents as a surrogate for truck crash counts using truck telematics data have shown promise in identifying potential hot spots with high crash risk (Kamla et al 2019). A 6-month study of drivers in Georgia traveling on freeways, arterials, and local roads found that those involved in a crash incident tend to more frequently hard brake (8.8 ft/s 2 ) than those not involved in crashes (Jun et al 2007).…”