Pub. 2 2019-2020 Issue 2

29 QUALITY IN PRESERVATION NOMINEE: PROJECT LOCATION: Stansbury Park, Utah PROJECT START: February 2019 PROJECT COMPLETION: August 2019 STANSBURY PARK 2019 SCRUB SEAL PROJECT TOOELE COUNTY W e placed scrub seals on several collector and local streets In Stansbury Park, Utah. These roads were good candidates for a scrub seal based on our condition inventory and the results of a geotechnical evaluation. We removed and replaced small sections of pavement that were displaying structural distress. The pavement sections were moderately to highly cracked but had ade- quate structural capacity. The project is in an urban setting in a subdivision with curb and gutter. It was the first time we had completed a scrub seal. A few years ago, we heard a speaker from Western Emulsion discuss scrub seal projects completed in California. We attended a UAPA lunch on a Geneva Rock scrub seal project for UDOT between Hurricane and St George. Based on their success and specifications from Peak Asphalt, we felt comfortable completing this project. This scrub seal application bridged the gap between a chip seal and performing a mill and fill asphalt overlay. The expectation is that by applying a rejuvenating emulsion followed by a scrub broom employing a simultaneous apply and scrub method, one can eliminate mass cracking and improve the quality and durability on roadways in high distress. The use of lightweight aggregate from Utelite and a smaller type “A” 3/8” chip gradation on the road surface produced a relatively smooth surface; local bicycle riders commented on the improved surface texture over a natural type “C”½” aggregate chip seal. The cracks were sealed, the color is black or dark grey, and the texture is uniform. The project was an overall success, but we learned a few things; for example, the application rate needs to be adjusted depending on howmany cracks are in each section of the road. Keeping emulsion off concrete waterways and curb and gutter requires a skillful distributor truck operator. The correct roads were selected, and we followed best practices. We pro- tected the asphalt surface from water infiltration and oxidization. The skid resist- ance and aesthetics were improved, and the cost was less than half the price of a mill and fill asphalt overlay. We expect to extend the life of these distressed road- ways by roughly 7-10 years. There were no accidents and no viable reports of damage. The traffic control plan was completed in-house by certified traffic control managers. Certified technicians placed the correct signs, and certified flaggers controlled the traffic. We used elec- tronic message boards placed on the roads in advance to alert the public to the possible delays during the project. 3