Preserving a Scenic Cape Cod Road

In 2007 Aggregate Industries developed an innovative new product designed to use warm mix technology by incorporating Sasobit wax in their liquid asphalt binders that would enable the company to enter the pavement maintenance market, which primarily consists of products such as chip seal, micro-pavements, and slurry seals which typically do not yield any structural improvement to the existing paved roadway surface.

Thin Lift benefits

Aggregate Industries Thin Lift surfacing solution is a hot mix asphalt surfacing material that was developed in conjunction with a leading university specializing in asphalt technology research.

The product is capable of fulfilling the same applications as chip seal, micro-pavements or slurry seals but does so in a more cost-effective fashion.

In addition, the product can incorporate warm mix technology which affords it some specific benefits unique to this particular product. Those include:

• Minimal road preparation prior to installation
• Utilization of a polymer modified asphalt binder which ensures good performance at both low and high temperature conditions and greater rut resistance
• Quicker opening to traffic, which reduces public inconvenience
• Greater integrity then alternative maintenance products currently available as a result of the aggregate composition of the material
• The ability to cover greater roadway surface with less material, significantly reducing job costs
• Ability to incorporate higher percentages of Recycled Asphalt Pavement (RAP)
• Minimal smoke emissions from manufacturing
• Reduced emissions and energy costs

The product developed by Aggregate Industries serves as an extremely robust alternative to typical roadway maintenance products and applications where traditional HMA overlays may not be necessary. It is most effective on residential and secondary roadways where moderate to well traveled usage is customary.

Road tested

Aggregate Industries demonstrated the product in Wellesley, MA. The project was the result of a search conducted by Department of Public Works Director Michael Pakstis for an alternative pavement material.

Pakstis' desire for an alternative maintenance product was prompted by residents that were unhappy with the loose stone and rough texture of their roadways that were the result of the chip seals which the town applied as a maintenance treatment.

After consulting with Aggregate Industries, the asphalt producer agreed to demo the product on the busy recycling center access road in Wellesley.

The roadway receives 1,200 residential cars a day and up to 2,400 cars on a weekend in addition to trucks that haul in construction and demolition debris. This traffic pattern made it a perfect roadway to demo the thin lift product.

Aggregate used a 7/8-inch-thick course of the mix, a dense-graded material containing 30% RAP and a proprietary warm-mix formulation. The results of the demonstration validated the product's performance, and it has since been added to the local specifications for asphalt maintenance treatments.

Receiving national attention

Aggregate Industries proved it is willing to stand behind the product when it lobbied the National Park Service and the Federal Highway Administration to re-open the specifications for a major job in Cape Cod. The job, which had been spec'd for 60,000 square yards of slurry seal, was switched to incorporate AI's thin lift product after the company made a value engineering case for substitution.

With the help of Lawrence-Lynch Corp., the project general contractor, the company once again proved their product provided greater value for the cost. Consequently, Aggregate Industries was awarded a contract to supply 3,000+ tons of the thin lift product for the Marconi & Marconi Beach Road project in Wellfleet.

Mike Norton, project manager for Lawrence-Lynch, says placement of the warm mix thin lift on the Marconi & Marconi Beach Road project was similar to working with a hot mix design.