ASTM D4791

ASTM D4791 – Standard Test Method for Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse Aggregate

Description:

Significance and Use

5.1 The particle shape of coarse aggregates influences the properties of some construction materials and may affect their placement and consolidation.

5.2 This test method provides a means for checking compliance with specifications that limit such particles or to determine the relative shape characteristics of coarse aggregates.

Scope

1.1 This test method covers the determination of the percentages of flat particles, elongated particles, or flat and elongated particles in coarse aggregates. Two procedures, Method A and Method B, are presented in this standard. Method A is a reflection of the original procedure as developed prior to Superpave and is intended for all non-Superpave applications. Method B is a comparison of the maximum particle dimension to the minimum particle dimension and is intended for use with Superpave specifications.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.2.1 Exception (regarding sieves, per Specification E11)—The values stated in SI units shall be considered standard for the dimensions of the wire cloth openings and the diameter of the wires used in the wire cloth. When sieve mesh sizes are referenced, the alternate inch-pound designations are provided for information purposes and enclosed in parentheses.