Pavement Condition Index Model for Mechanistic–Empirical Design of Airport Concrete Pavements Considering Environmental Effects

Abstract

A transfer function is the main model of a design program that correlates mechanistically calculated damage to a pavement with the actual field distress. In this study, a pavement condition index (PCI) model that reflects environmental and traffic loads was developed as a transfer function for a design program for airport concrete pavements. Seven runways from five airports in Korea, for which design data were available, were selected as target runways, and their design, traffic, and weather data were collected. The minimum tensile stress of the slab generated by environmental loads and the maximum tensile stress induced by combined environmental and traffic loads were calculated by conducting a three-dimensional finite element analysis. The cumulative fatigue damage to the target runways was calculated by substituting the climatic conditions and traffic volume into the fatigue model, which considered the minimum and maximum tensile stresses. The PCI, which was uniformly and varyingly distributed according to pavement age, was adopted as the indicator of actual field distress, whereas the previously used structural condition index was mostly 100 because no structural distress occurred, regardless of the pavement age. The PCI model was established via multi-regression analysis to predict field PCIs using mechanistically calculated cumulative fatigue damage and pavement age as independent variables. The actual and predicted PCIs of the target airports were compared to validate the PCI model.