Task Force Report on ASTM D 2419: Sand Equivalent Value of Soils and Fine Aggregate, Prepared for ASTM Subcommittee D 04.51

Abstract

Abstract This interlaboratory study compared ASTM D 2419 test results using three different sample preparation techniques. Established preparation Procedures A and B were compared against a new proposed Procedure C, currently being used by the Georgia Department of Transportation (DOT). Sand equivalent (SE) testing was done at eight different laboratories, and the data were analyzed by ASTM Practice for Conducting an Interlaboratory Test Program to Determine the Precision of Test Methods (E 691) computer program, Interlaboratory Data Analysis Software. Results of this study conclude that the proposed Procedure C gives essentially the same results as Procedure A and is easier and less cumbersome to perform. Results also showed that there is no reason to differentiate between SE values above or below 80 when applying a precision statement. The second part of this study compared SE results from tests using minus No. 4 (4.75-mm) material against tests using minus No. 10 (2.0 mm). It was felt that SE testing with larger top-size particles, particularly with flat or elongated aggregates, tends to trap plastic fines and gives poorer results than tests run with smaller top-size particles. This study shows that tests using minus No. 10 (2.0-mm) material gives more consistent results than using minus No. 4 (4.75 mm).