National Concrete Pavement Technology Center

Project description

Centerline and shoulder rumble and mumble strips have long served as a safety treatment tool to alert motorists to realign their vehicles to the driving lane. As part of the 2018 Midwest and Southeast Pavement Preservation Research Survey, rumble strip preservation was identified a research need. Many rumble and rumble strips are installed as part of contract overlay projects where pavement thicknesses can be as thin as 1 inch. Rumbles are then ground into the new overlay effectively reducing the thickness in the grounded areas to ½” or less. In addition as a result the ground pavement area making up the rumble strip generally displays premature deterioration and requires ongoing maintenance to keep the roadway free of pot holes. The purpose of this research is five fold: (1) Threshold for minimum thickness of pavement or pavement overlay for rumble and mumble strips to be milled; (2) Threshold for the age of pavement or pavement overlay for rumble and mumble strips to be milled; (3) Effects of preservation strategies on pavement markings that are maintained or preserved on rumble and mumble strips; (4) Effects of sealers, rejuvenators and other preservation strategies on the performance of rumble and mumble strips; and (5) Strategies to maintain and preserve rumble and mumble strips to meet the design life of the pavement or pavement overlay. Much of the research done on the topic references the performance of rumble strips on how they perform their function in keeping motorists in their driving lane. More research is needed to determine the effects of rumble strips on older pavements and thin lift pavement overlays and offer solutions to owner agencies on how to maintain and preserve them for the life of the pavement. The objective of this research is to develop a guide to maintain and preserve rumble and mumble strips that last as long as the main line pavement where they were installed.