The Marathon County Highway Department in central Wisconsin is hard at work maintaining over 600 miles of highways. Their commitment to a safe and high-quality transportation system has led them to leverage innovative asphalt products and technologies to achieve roadway longevity.
The county planned improvement and resurfacing of County Trunk Highway (CTH) KK between Rib Mountain and Mosinee just south of Wausau in late summer of 2024. They also planned to install both centerline and shoulder rumble strips as safety tools throughout the project due to heavy traffic and use by bicyclists. With such a high-profile project at hand, county personnel are eager to ensure this investment stands the test of time.
The Joint Problem
Historically, the longitudinal construction joints and rumble strips are the first parts of a pavement to fail. Water permeates the tiny air voids at joints, causing cracking and delamination of the surface. This is exacerbated in cold climates with prevalent freeze-thaw cycles. In many cases, longitudinal joints, especially with rumble strips on top, only last 4-5 years before requiring maintenance.
The Joint Solution
To avoid the age-old issue of longitudinal joint deterioration, for the first time, Marathon County elected to include a void reducing asphalt membrane (VRAM) in the plans for the refreshed CTH KK. With a VRAM under the centerline rumble strip, this highway’s longitudinal joint will have a chance of lasting far more than 15 years, extending the life of the entire pavement and saving lifecycle costs.
Project Details
- Owner: Marathon County Highway Department
- Prime Paving Contractor: Marathon County Highway Department
- Mix produced by American Asphalt (a Mathy Company)
- Support of material transfer vehicle (MTV) provided by American Asphalt
- VRAM Applicator: Evergreen Roadworks (ProTack)
- Location: County Trunk Highway KK, Marathon County, Wisconsin
- VRAM Application: September 9, 2024
VRAM Application
At 6 am on September 9, applicator Evergreen Roadworks sprayed VRAM on a milled surface at the location of the future centerline joint targeting a rate of 0.95 lb/ft for an 18” width. Over the course of the morning, about 6 miles of VRAM was sprayed. Paving began shortly after the VRAM application.
Personnel onsite included Dan Swiertz from Asphalt Materials Inc. (AMI) Specialty Products and Ken Schakelman and Greg Schnell from AMI’s Wisconsin location, H.G. Meigs. They were joined onsite by Marathon County’s Deputy Director Kevin Lang.
Evergreen Roadworks (ProTack) applies J-Band®, the premier VRAM
Paving Observations
In addition to VRAM, the project plans called for milling off the existing surface, wedging/reprofiling where necessary and overlaying with 2” of WisDOT 4 MT (Medium Traffic) hot mix. The plans included 17’ lane widths to accommodate shoulder rumble strips.
Paving took place over the next week, heading south from CTH N. Prior to paving, the milled surface and the VRAM were tacked using SS-1h emulsion. The paving train consisted of a material transfer vehicle (MTV) feeding a county-operated paver, followed by a vibratory breakdown roller and static steel drum finish roller.
The heat of the HMA lift and the pressure of the vibratory rollers cause VRAM to migrate upward, filling air voids in the pavement. This provides better relative density and cracking resistance in the area around the joint.
Sinusoidal geometry rumble strips were milled into the surface over the centerline and shoulder. This took place on September 18 with striping on September 20. Follow-up pictures were provided by Jesse Werner of HG Meigs on September 26.
This freshly completed project on CTH KK is set up for safety and longevity. With rumble strips, Marathon County has significantly reduced the risk of lane departure crashes. However, this county highway department has not forgotten the impact rumble strips can have on mixture performance and joint deterioration. By reinforcing the centerline with VRAM, they are deferring the costs and risks of centerline maintenance, saving time, money and lives.
Final surface with rumble strips and striping
Resources
Are you curious if a VRAM could save time, money and lives on your roadways? Try our ROI Calculator or reach out to our team here.
Editor’s Note:
J-Band®, the premier VRAM, was created in the labs of the Heritage Research Group (HRG) and is a product of Asphalt Materials, Inc. (AMI).
