ASTM D4791-19 PDF Download

ASTM D4791-19 is a standard test method that is used to determine the percentages of flat particles, elongated particles, or flat and elongated particles in coarse aggregates. This standard is important because the shape of coarse aggregates can impact the properties and placement of construction materials.

The test method provides a means for checking compliance with specifications that limit the presence of these particles or for determining the relative shape characteristics of coarse aggregates. There are two procedures presented in the standard: Method A and Method B. Method A is the original procedure developed prior to Superpave and is suitable for all non-Superpave applications. Method B, on the other hand, compares the maximum particle dimension to the minimum particle dimension and is intended for use with Superpave specifications.

Additionally, the standard specifies that the values stated in SI units should be considered standard for the dimensions of the wire cloth openings and the diameter of the wires used in the wire cloth. However, the inch-pound designations are also provided for information purposes.