University of Nebraska, Lincoln; NE DOT
Center lines, Deterioration, Fatigue (Physiological condition), Field tests, Head on collisions, Pavement performance, Rumble strips
Centerline rumble strips are primarily installed on the centerline of undivided two-lane and two-way roadways to alert drivers who are moving out of their intended travel lane. The main purpose of the centerline rumble strips is to reduce cross-over crashes such as head-on crashes, opposite-direction sideswipe crashes, and front-to-side crashes, which are usually caused by inattentive, distracted, drowsy, or fatigued drivers. Despite the safety benefit, several pavement performance concerns associated with the centerline rumble strips have been reported (Torbic 2009). In particular, the centerline rumble strips milled over or adjacent to the centerline joint (even if it is hardly distinguishable), which is a damage-sensitive region of pavement, can increase or accelerate deterioration and degradation of the pavement structure. It also requires more maintenance and attention due to potential safety concerns. To reduce pavement damage, the centerline rumble strips design has been modified from a single strip over the centerline joint to dual strips straddling the joint in our state. The modified design could decrease pavement damage; however, there is still a pressing need to improve the centerline rumble strips design. To maximize the safety benefits of the centerline rumble strips and minimize pavement damage, a series of research activities needs to be performed. Firstly, configurations and dimensions of the centerline rumble strips built or tested by other states need to be collected. Surveying the corresponding lane widths required or suggested by other Departments of Transportation (DOTs) is also necessary. This will result in findings that can be used to improve the current dual rumble strips so as to satisfy expected structural performance as well as roadway safety requirements. Then, the proposed centerline rumble strips design will be evaluated and compared with the current design through structural model simulations and actual field tests. With the limited time and scope of this stage, this proposal primarily intends to first, collect data and practices from other states in order to recommend modifications to our current rumble strip design, and second, evaluate the recommended design through model simulations that compare the newly proposed design with current rumble strip design practices. Field test evaluation of the modified design can then be planned in a follow-up research effort.