Impact of Crack Sealant on Pavement Skid Resistance

Crack sealing is often a cost-effective preventive maintenance strategy for prolonging pavement service life when applied to pavements in relatively good condition. Crack sealing is generally ineffective for extending the life of heavily cracked pavements. However, crack sealing is often applied to pavements with extensive cracking. The application of crack sealing to pavements with extensive cracking can pose a skid resistance hazard. This study investigates the relationship between the amount and distribution of crack sealant application and pavement skid resistance. Locked-Wheel Skid Tester (LWST) testing was conducted on several pavement projects in North Carolina, United States, with varying amounts and patterns of crack sealant. Images of the locations of LWST testing were obtained and processed to determine the percentage of the pavement surface area covered by crack sealant. A relationship between the percentage of the wheel path covered by crack sealant and LWST results was established that demonstrates the application of high amounts of crack sealant to the wheel path can pose safety hazards. The effect of crack sealant on pavement skid resistance is a function of the existing pavement’s frictional characteristics. The results of this study highlight the need for the development of crack sealant specification provisions to avoid the loss of skid resistance.