Evaluation of Seal Coating Treatments to Manage Temporary Pavement Paint Markings during Highway Construction

Abstract

Pavement markings are the most widely used road traffic control device. However, such markings have a finite lifespan due to normal wear and tear of the road. They must be eventually removed and subsequently replaced. During highway construction, the use and subsequent removal of temporary pavement markings are common necessities. Current methods to remove markings have often been unsatisfactory, leaving pavement scars that can be mistaken for lines. Instead of removing existing markings, this paper presents seal coating treatments as a means of obscuring temporary pavement paint markings. These treatments would not adversely affect the pavement and would not leave any trace of the marking. Two experimental seal coating methods, modified slurry-seal coat and modified sand-seal coat, were developed and evaluated. The modified slurry-seal coat treatment adequately covered the pavement markings and attained satisfactory friction test results. However, the modified sand-seal coat treatment provided exceptional performance with regard to friction, coverage, and durability, proving to be a practical and successful method for covering temporary pavement paint markings. Cost analysis results indicated that the modified sand-seal coating could be installed at less cost than that incurred in current removable tape covering and mechanical painted traffic line removing methods. Finally, a draft specification for covering existing pavement markings with a sand-seal coat was developed, and the research team recommends the adoption of the modified sand-seal coat treatment as an optional method for the removal of temporary pavement paint markings.