U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Center line, edge line, and shoulder rumble strips are extremely effective in reducing severe roadway departure crashes at a low cost. Rumble strips use both noise and vibration to alert the driver that he or she is leaving the travel path. There are many pavement-related variables that play an important role in the successful implementation of rumble strips, such as condition, age, type, thickness, location of longitudinal joints, and the type of milling equipment used for installation.
|State||Required Pavement Thickness for Rumble Strip Implementation by State|
|Pennsylvania||Less than 1 year old â€“ 1.5"
Older â€“ greater than 2.5"
Joints are an inherent weak spot in the pavement, but due to construction practices they are often the ideal location for rumble strips. Milling rumble strips into longitudinal joints was a concern expressed by many among the pavement community during the early stages of rumble strip implementation. As agencies have experimented with rumble strip installations, practitioners have generally found that longitudinal joints in good to fair condition can have rumble strips milled into them without accelerating deterioration.
Although the location of longitudinal joints is not typically a factor in determining whether or not rumble strips should be installed, various practices are used by a few States to avoid cutting rumble strips directly into the joint, such as:
Milled rumble strips are installed with a rotary cutting head that can be adjusted for the desired dimensions and spacing.
There are a few issues to consider at the beginning of construction to ensure a successful installation:
Installation of raised rumble strips depends on the product used. The product will determine the dimensions, but the proper location in relation to the pavement markings must still be considered. Ensuring proper adhesion to the pavement is also critical to the performance. For products that are installed within the pavement marking, spacing and coverage should be verified.
Milled rumble strips typically require little to no maintenance. Some agencies have used asphalt fog seals where rumble strips are milled into joints; however, most States do not perform any preventative maintenance treatments on their rumble strips. When pavement markings will be placed within the rumble strips, the marking material may seal the joint, making the fog seal superfluous. In addition, fog seals have proved to be incompatible with the thermoplastic material sometimes used for pavement markings.
The following resources provide more details related to rumble strip use and design: