Contrast pavement markings are a means to improve the daytime visibility of the markings by providing better contrast with the pavement surface. This research used online surveys completed by State Departments of Transportation (DOTs) and each district of the Texas Department of Transportation (TxDOT) to document the state-of-the-practice with respect to contrast pavement markings. A laptop survey including video of a real roadway with simulated contrast markings was conducted to determine driver understanding and preference with respect to contrast markings. Contrast markings were found to be used in 64 percent of the districts in Texas and in 64 percent of the responding states. The most frequently used contrast marking design is the bordered design where a white marking is highlighted with black markings along the longitudinal sides. While driver preference suggests that the lag design (black marking placed after the white marking) is less preferred to the bordered design, the lag design is normally much less expensive. The bordered design is currently provided with tape products, which have a high initial cost, therefore a non-tape marking alternative of the lag design is also recommended as a low-cost alternative. The study showed that some drivers do not understand the meaning of the contrast markings. Therefore the use of only the bordered and lag designs are recommended to limit the number of contrast marking designs in hopes to minimize driver confusion.
Abstract