Friction Performance Models for Network-Level Pavement Friction Management

Reliable pavement friction performance models are crucial for effective pavement management, affecting both the safety and maintenance costs. Existing models face challenges, including their reliance on laboratory test data, which is not always accessible at the network level, and their inability to capture potential increases in pavement friction shortly after construction or maintenance. To address these issues, this study proposed an exponential decay model that accounts for such potential friction increases as well as exploiting variables that are easily accessible at the network level within a state department of transportation’s pavement management system. Two sets of models were developed: (i) a statewide model for use in areas with limited data availability and (ii) regional models that incorporate adjustment factors for regional conditions. Both model types were validated against actual field measurements, demonstrating acceptable goodness-of-fit for pavement management application. The models showed that increased annual average daily traffic accelerated friction decay, whereas higher truck traffic percentages and higher temperatures were associated with higher terminal coefficients of friction. Conversely, higher precipitation increased the difference between terminal and initial coefficients of friction. Among pavement types, jointed concrete pavements maintained a stable coefficient of friction longer than continuously reinforced concrete pavements and both thick and thin asphalt concrete pavements. This study enhances pavement friction management by providing models that accurately reflect field conditions and regional variations. These models are essential for optimal long-term pavement management, such as the development of 4- and 10-year management plans.