Date of this Version
Kim, Y-R; You, T; Rilett,L.R. "Design and Evaluation of Modified Centerline Rumble Strips" (2017) Nebraska Department of Roads Research Report
A centerline rumble strip (CLRS) is primarily installed on the centerline of undivided two-lane and two-way roadways to alert drivers that they are moving out of their intended travel lane. The main purpose of CLRSs is to reduce crossover collisions typically caused by inattentive, distracted, drowsy, or fatigued drivers. Despite the safety benefits, CLRSs that were milled over or adjacent to the centerline joint may increase or accelerate the deterioration and degradation of the pavement structure, which has been observed in Nebraska pavements. In this research project, new (or modified) CLRS designs were sought to reduce pavement damage, while satisfying the safety purpose of CLRSs. A literature review including a survey of the CLRS design practices in different states and discussions with the project technical advisory committee (TAC) members resulted in three proposed modified CLRS designs. Then, the current (8”-4”-8” with 0.5” depth) and modified designs (6”-6”-6” with 0.5” depth, 5”-7”-5” with 0.375” depth, and 6”-8”-6” with 0.5” depth) were evaluated using finite element pavement modeling and simulations to assess the stress and damage potential of pavements associated with the different CLRS designs. Two primary types of pavements in Nebraska (i.e., composite pavements and concrete pavements) were considered. Model simulation results demonstrated that pavements with CLRSs showed higher stress than pavements without CLRSs. In addition, each CLRS design induced different stress distributions (and damage potential) due to different tire-pavement contact. The highest stress typically occurred at the corner/edge of the CLRS, and the current CLRS design (i.e., 8”-4”-8” with 0.5” depth) produced higher stress (or damage potential) than the modified designs in both types of pavements. A comparison of the three modified CLRS designs in this study showed that one modified design (6”-6”-6” with 0.5” depth) generally yielded the lowest stress. This research provides preliminary insights into how a modified CLRS design can reduce the pavement damage, while the findings should be validated through field testing in a follow-up effort.