00494757

Component

http://onlinepubs.trb.org...trr/1989/1230/1230-005.pdf

https://scholar.google.co...rien&publication_year=1989

Embedment characteristics of drop-on moistureproofed and uncoated glass spheres and their subsequent retroreflectivity were evaluated subjectively in various types of hot-applied thermoplastic traffic markings by illuminating test panels in a dark room. In all of the hot-applied thermoplastic traffic marking types tested, uncoated drop-on spheres were generally overembedded because of positive wetting of the spheres by the thermoplastic traffic marking, and their retroreflectivity varied. The use of moistureproofed drop-on spheres in various thermoplastic traffic marking types resulted in optimal bead embedment with subsequent excellent retroreflectivity. The optimal rate of glass sphere application in all of the thermoplastic marking types was found to be 10 lb of moistureproofed glass spheres per 100 sq ft -- this rate enhanced retroreflectivity, bead embedment, and coverage. The retroreflectivity of the standard gradation of glass spheres may be enhanced in all of the thermoplastic types by increasing the percentage of spheres retained on U.S. sieves 30, 40, and 50 and by increasing the overall rounds from 70 to 80 percent.

This paper appears in Transportation Research Record No. 1230, Work-Zone Traffic Control and Tests of Delineation Material. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

01414222

p. 37-44

1989

Transportation Research Record

030904961X

Figures (3) ; Photos (13) ; References (4) ; Tables (5)

Anchoring; Glass beads; Retroreflectivity; Road markings; Testing; Thermoplastic materials; Waterproofing

Application rate; Embedment

Highways; Operations and Traffic Management; I73: Traffic Control

TRIS, TRB, ATRI

Jun 30 1990 12:00AM

• CHARACTERISTICS OF CONSTRUCTION-ZONE ACCIDENTS
• DURABILITY TESTING FOR RETROREFLECTIVE SHEETINGS
• IN-SERVICE EVALUATION OF THERMOPLASTIC AND TAPE PAVEMENT MARKINGS USING A PORTABLE RETROREFLECTOMETER
• LARGE GLASS BEADS FOR PAVEMENT MARKINGS
• RESEARCH ON RAISED PAVEMENT MARKERS
• TRAFFIC CONTROL FOR SHORT-DURATION MAINTENANCE OPERATIONS ON FOUR-LANE DIVIDED HIGHWAYS
• WORK-ZONE TRAFFIC CONTROL CONCEPTS AND TERMINOLOGY