Study of a Glass Bead Gun Angle When Applying Glass Beads on Waterborne Paint

摘要

Retroreflectivity of pavement markings is an important measure of their nightime effectiveness. In Pennsylvania, retroreflectivity is achieved by placement of spherical glass beads in the pavement marking paint using a bead on waterborne paint to determine which angle(s) result in optimal nighttime visbility from a paint truck moving at various speeds. A variety of laboratory and field experiments were conducted to evaluate pavement marking performance, induding digital image processing, scanning electrod microscopy, high-speed video imagery, and detection distance measurements from research participants, and retroreflectivity measurements. The laboratory tests were subjected to accelerated wear and weather exposure. The results indicate that the 12 mph truck application speed and -20 degree bead gun angle provides the optimal nighttime visibility based on the laboratory and field evaluations performed in the present study.