Examining the Effectiveness of Preventive Pavement Treatments in Freeze Climatic Regions Using the LTPP Database

Abstract

Preventive pavement maintenance treatments remain essential in prolonging the lifespan and ride quality of pavements, but their performance could vary depending on the environmental and climatic conditions. The purpose of this study is to evaluate both the short- and the long-term performance effectiveness of slurry seal, chip seal, crack seal, and asphalt thin overlay in the wet freeze and the dry freeze regions of the United States and Canada using the long-term pavement performance program (LTPP) database. Performance jump and weighted distress were used as measures of effectiveness for longitudinal cracking (nonwheel path), transverse cracking, fatigue cracking, rutting, and International Roughness Index. A generalized least square regression and post hoc Dunnett’s test were used for the statistical analysis. The results show that climate (dry freeze and wet freeze) significantly influenced the short-term performance of treatments regarding longitudinal cracking and transverse cracking, but this factor did not significantly impact the long-term performance of any of the treatments. Asphalt thin overlay was the most effective for both the short- and long-term treatment of all the pavement distresses under study. Aside asphalt thin overlay, slurry seal and chip seal were effective for treating short-term fatigue cracking and longitudinal cracking. Chip seal was only effective in the long-term treatment of longitudinal cracking and fatigue cracking. Higher pretreatment roughness significantly increased the chances of posttreatment pavement roughness and transverse cracking. Higher truck traffic loading also led to higher rutting in pavements. The results here provide insights to pavement maintenance professionals in the industry on the selection of the most appropriate treatments for pavement sections in these freeze regions.