, Professor, Civil, Environmental and Geo-Engineering
Randal Barnes, Associate Professor, Civil, Environmental and Geo-Engineering
Ride quality is one of the most important indicators of pavement condition; poor ride quality causes complaints from the traveling public and often triggers pavement rehabilitation. Negative changes in ride quality have traditionally been attributed to increases in pavement surface distress due to repeated heavy axle loading and material surface deterioration due to weather exposure. The effects of other environmental factors, such as frost heave, have not been sufficiently studied. The objective of this research was to evaluate the contribution of frost heave to seasonal and long-term changes in the ride quality of roads in Minnesota using pin elevation measurements and pavement performance data from the MnROAD testing facility. This project considered both asphalt and concrete pavements, and evaluated the ability of various design features to mitigate climatic effects. Elevations of frost pins embedded in MnROAD test sections were measured over a four-year period, and pin elevation changes were analyzed to show the amount of frost heave and degree of frost heave uniformity within a cell. Various plots were made to show the elevation change and interquartile range of the pins over time. Statistical approaches such as visual analyses, student hypothesis testing, and ANOVA analysis were used to evaluate the effect of pavement design features on frost heave and roughness. Ultimately, the effects of frost heave on ride quality deterioration for flexible and rigid pavements could not be confirmed or statistically rejected in this study. Since no firm conclusions could be made from the data concerning a seasonal effect on IRI measurements, no seasonal adjustment factor for IRI measurement was recommended for use in a pavement management system.