Since 2002, J-Band has been setting a new standard across many states as a proven approach that protects centerline joints from premature failure. Asphalt Material’s J-Band product is a void reducing asphalt membrane (VRAM). This particular project took place in May of 2021 in central Indiana between the towns of Rushville on the west end and Glenwood on the east end.
The J-Band application began early in the morning with material being placed on a newly milled surface with a painted guideline. The specification called for 1.51 lb/ft of VRAM at 18” wide per the InDOT Special Provision for 2” Surface Course 3, 70, 9.5mm HMA. Temperatures recorded at the start of application were noted as ambient 63°F; existing milled surface 73°F. Temperatures in the afternoon would climb to 85°F ambient under cloudy skies and 117°F on the milled surface.
The width of the VRAM application was 18”. The crews were brooming the centerline to provide a clean surface for application. The first application yield check showed 1.20 lb/ft. A second check taken within 500 feet of the first one showed a yield of 1.50 lb/ft. Our application yield check showed 1.38 lb/ft as we applied 18,020 pounds over 13,055 feet.
Depending on the specifications in each state, there may be an upper limit on temperature. In addition, width and application rates are also specified. Measures should be taken in all cases to ensure compliance with specifications.
Shortly after the VRAM was applied, paving began. Hot mix asphalt (HMA) was consistently at 285°F. The ambient temperature was 68°F and the existing milled surface was 72°F. These would steadily rise to 86°F ambient and 117° F on the surface during the day. Paving speed was 22 fpm to start and maintained throughout the day. When the third roller was added it would make 5 passes in static only. VRAM was migrating 5/8” to ¾” into the mat prior to rolling. After rolling a strong presence of shadow could be seen on the surface where VRAM was placed underneath.
Photos from the project can be viewed below.
In every state except Illinois, the product is specified as VRAM or Void Reducing Asphalt Membrane. However, in Illinois the product is specified as LJS or Longitudinal Joint Sealant. The VRAM product from Asphalt Materials is called J-Band and was created in the labs of The Heritage Research Group. Also, depending on the situation VRAM can be sprayed at different width’s. This article notes 18” which is a typical application width for centerline applications.
J-Band® is a product of Asphalt Materials, Inc. and was created in the labs of The Heritage Research Group.