Assessing Pavement Crash Susceptibility for Consideration in Pavement Management Decisions

Traffic crashes remain a major threat to road safety, with many crash-related casualties and large economic losses occurring every year. Generally, crashes are complex events involving interactions between a wide range of factors, including those related to the driver, vehicle, roadway, traffic, and weather at the time and place of the crash. Whereas numerous road safety studies investigated the contribution of various factors to crash frequency and severity, a better understanding of the combined effect of pavement condition on crash occurrence is needed to assist pavement managers identify appropriate pavement safety improvement projects. Pavement surface condition factors are of particular interest to highway agencies because they fall directly within their control and can be addressed through maintenance and rehabilitation (M&R) projects. This study introduces crash susceptibility as a new parameter useful for incorporating safety in pavement management decisions. In this study, crash susceptibility is defined as the probability of a crash occurring on any given pavement segment within a given year. Logistic regression was employed to estimate the likelihood of crash occurrence on asphalt concrete pavement (ACP) with and without surface treatment (ST) or seal coat as a function of the pavement condition (roughness, macrotexture, skid resistance, and distresses), while considering traffic volume, road geometrics, and environmental conditions. This study utilized three years (fiscal years 2021–2023) of crash, pavement condition, and site condition data from Texas. The results show that for both asphalt pavement types, increased roughness contributes to higher crash susceptibility, whereas increased skid resistance contributes to lower crash susceptibility. However, the effects of these pavement conditions are more significant on pavements without ST or SC. This study also shows that higher macrotexture is associated with a reduction in crash susceptibility for pavements without ST or SC. Of the individual pavement distresses examined, only potholes show a significant increase in crash susceptibility, and this effect is observed only for pavements with ST or SC. Other pavement distresses, including rut depth, raveling, flushing, cracking, failures, and distress score, were found to have no significant impact on crash susceptibility. Highway agencies can use this study to assess the influence of pavement surface conditions on crash susceptibility and to support data-driven decisions for roadway maintenance and safety improvements.