ASTM D7971-20 PDF Download
Standard EN
Standard Guide for Measuring Roundness of Glass Spheres Using a Flowing Stream Digital Image Analyzer
Also Known As:
The ASTM D7971-20 standard addresses the importance of measuring the roundness of glass beads in pavement marking systems. The roundness of these beads significantly affects the retroreflective efficiency of the pavement marking system.
This guide specifically focuses on characterizing the roundness of glass beads for compliance testing against standard specifications for glass beads in pavement marking applications. It does not cover potential industrial applications beyond the measurement of roundness of glass beads for pavement markings.
The guide outlines the determination of roundness using a flowing stream digital analyzer. The typical gradations for pavement marking systems are defined in ranges from Type 0 through 5 in AASHTO M247. The guide also provides options for presenting the roundness data in different formats to meet the requirements of the agency pavement marking material specifications. The standard format for presenting the roundness data is usually as Percent True Spheres relative to a series of standard ASTM sieve sizes.
| Descriptors | roundness, gradation, flowing stream digital image analyzers, pavement marking materials, glass spheres,Glass Products,Pavement Marking Materials,Physical Process,Physical Properties,Process Stream Analyzers |
| ICS Codes | 93.080.20 - Road construction materials |
| Language(s) | English |
| File Size | 122.9 KB |
