Pub. 1 2018-2019 Issue 2

You could bring out the big guns and remove and replace the pavement. However, according to the American Road and Transportation Builder’s Assocation, the average cost for milling and resurfacing a four-lane road is $1.2 million per lanemile. 1 Of course, you only have a small window of opportunity for major construction the likes of a remove and replace, and asphalt is only available during certain months of the year. Asphaltic overlays or skin patching may only delay the inevitable, resulting in reflection cracking, which soon places you right back at square one. But there is another option, a budget-conscious, long-term solution called mastic. While mastic asphalt has been in use since 1837 as a building material, the term mastic has recently been applied to a relatively new asphalt-based, polymer-modified pavement preservation product. 2 In fact, there was quite a buzz about mastic materials echoing through the conven- tion halls at UAPA’s annual conference this past February What is Mastic? Pavement mastic is a hot-applied, asphalt-basedmerger of bitumen, poly- mers, and aggregate. This particular preservation material combines the flexibility and moisture sealing capa- bility of sealant with the load-bear- ing capacity of pavement. Versatile, cost-conscious materials, mastics are suited for wide cracking, fatigue cracking (alligatored areas), cupping, shallow depressions, utility cuts and trenches, raveling, deteriorating shoul- ders and seams, and overlay or seal coating preparation. Applying Mastic Unlike crack sealant, however, applying mastic requires the use of amasticmelter, which has a hydraulic agitator to keep the aggregate suspended in the binder. Because they are specialized pieces of industrial equipment, mastic melters are only available to be purchased from a small number of manufacturers, such as Crafco andMarathon. Contractors and municipalities canbuy their ownmachine or seek rental opportunities with mastic suppliers and melter dealers. Mastic preservation materials: Deliver greater flexibility than surround- ing pavement.  Impede further pavement deterioration.  Retard reflection cracking.  Adhere to surrounding pavement.  Seal out moisture.  Are self-leveling.  Require no compaction.  Can be applied in winter conditions. Tips for Working with Mastic:  Clean and dry the breach to improve material adhesion.  n Follow the manufacturer’s heating instructions and avoid overheating, which canproduce a less homogenous material and reduce performance.  Smooth and level material while still hot, as mastics are stiffer and less manipulable when cooled.  Cycle tools to ensure they remain hot for optimal material manipulation.  Do not heat finishing tools above the maximum safe heating temperature of the product.  Skid resistance, appearance, and time-to traffic may be improved by spreading additional aggregate, known as “topping stone,” onto the surface of the mastic material before it cools and hardens. Untreated, large or extensive crack- ing will eventually lead to the dreaded pothole, so maintaining pavement with a mastic product is imperative to avoid- ing the liability that comes with larger voids and severely deteriorating road- ways. Eventually, with thermal expan- sion and contraction cycles and water penetration into the base, even those potholes will get out of hand. Then, the department in charge may be left with little choice but to repave, and federal, state, and municipal budgets may not be able to keep up. Modern crack sealants provide con- tractors, state and local agencies, and municipalities with a solid first line of defense (as well as a budget-saving alternative to repaving). But, even in the event that some of those pesky cracks manage to get out of hand, new, hot-applied, asphalt-based mastic products provide a viable, effective backup plan. 3 Even in the event that some of those pesky cracks manage to get out of hand, new, hot-applied, asphalt-based mastic products provide a viable, effective backup plan. 2 “A Short History of Mastic Asphalt,”Mastic Asphalt Council, accessed July 3, 2018, http://masticasphaltcouncil.co.uk/news/a-short-history-of-mastic-asphalt/ 1 “HowMuchDoes It Cost to Build aMile of Road?”, AmericanRoad and TransportationBuilder’s Assocation. Accessed July 3, 2018, https://www.artba.org/about/faq/ 25