NCHRP 743 Predicting the Initial Retroreflectivity of Pavement Markings from Glass Bead Quality Accession Number: 01475102 Blurb URL: Record URL: Availability: Transportation Research Board Business Office 500 Fifth Street, NW Washington, DC 20001 USA Order URL: Find a library where document is available URL: Abstract: This report describes a proposed laboratory test method to predict the initial retroreflectivity of pavement markings in the field based on the quality of the applied glass beads. Thus, the report will be of immediate interest to state materials and maintenance engineers with responsibility for specification and placement of pavement marking materials. The project team conducted a combined laboratory and field experiment to develop, verify, and validate the proposed test method. The laboratory experiment addressed the characterization of glass beads and identified a drawdown test as a promising method to relate the laboratory retroreflectivity of glass beads to initial pavement marking retroreflectivity. The field experiment successfully verified and validated the laboratory results through a series of pilot- and full-scale pavement marking applications. Finally, the variability of the drawdown test method was estimated through a modified interlaboratory study. The study included five laboratories, which used the same set of beads and the same paint to conduct the drawdown test independently. Analysis of the results demonstrated that the test method is repeatable and reproducible. The report fully documents the research; a proposed laboratory test method in AASHTO standard format is presented in Chapter 5: Findings and Recommendations. In addition, the report includes Appendix A: Explanation for Statistical Graphing. Numbers: Project 04-38
NCHRP 743 Predicting the Initial Retroreflectivity of Pavement Markings from Glass Bead Quality Accession Number: 01475102 Blurb URL: Record URL: Availability: Transportation Research Board Business Office 500 Fifth Street, NW Washington, DC 20001 USA Order URL: Find a library where document is available URL: Abstract: This report describes a proposed laboratory test method to predict the initial retroreflectivity of pavement markings in the field based on the quality of the applied glass beads. Thus, the report will be of immediate interest to state materials and maintenance engineers with responsibility for specification and placement of pavement marking materials. The project team conducted a combined laboratory and field experiment to develop, verify, and validate the proposed test method. The laboratory experiment addressed the characterization of glass beads and identified a drawdown test as a promising method to relate the laboratory retroreflectivity of glass beads to initial pavement marking retroreflectivity. The field experiment successfully verified and validated the laboratory results through a series of pilot- and full-scale pavement marking applications. Finally, the variability of the drawdown test method was estimated through a modified interlaboratory study. The study included five laboratories, which used the same set of beads and the same paint to conduct the drawdown test independently. Analysis of the results demonstrated that the test method is repeatable and reproducible. The report fully documents the research; a proposed laboratory test method in AASHTO standard format is presented in Chapter 5: Findings and Recommendations. In addition, the report includes Appendix A: Explanation for Statistical Graphing. Numbers: Project 04-38
NCHRP-600-808-Report.docx