Eight experimental bead types in addition to Kentucky's currently used bead were applied with standard striping equipment at a field test location. Reflectivity measurements using a portable retroreflectometer were conducted, along with visual observations, to rate each bead type. The objective was to determine whether any of the experimental beads was superior to the currently used bead, and if so, would they be economically feasible for widespread use. The differences in bead types involved gradation, refractive index, and surface coating. Based on performance and economic considerations, it was recommended that Kentucky change its bead gradation specifications to correspond to that for the fine-gradation bead used in this study. The bead type termed "finegradation" in this study did not involve an unusally finely graded bead. It was considered a fine-gradation bead in comparison to Kentucky's currently used bead which has a higher percentage of large beads (beads retained on the No. 30 sieve). No changes in the presently used refractive index or surface coating were recommended.
Digital Object Identifier
Agent, Kenneth R. and Pigman, Jerry G., "Performance Evaluation of Experimental Paint-Stripe Beads" (1983). Kentucky Transportation Center Research Report. 1396.