Similar International Standards
ASTM C136 / C136M-19ASTM International (US)
HighCurrent
Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates
Covers the determination of particle size distribution of aggregates by sieving.
ASTM D4791-19ASTM International (US)
MediumCurrent
Standard Test Method for Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse Aggregate
Covers determination of flat/elongated particles, analogous to IS code's flakiness/elongation.
BS EN 933-1:2012BSI (UK) / CEN (Europe)
HighCurrent
Tests for geometrical properties of aggregates - Part 1: Determination of particle size distribution - Sieving method
Specifies the reference method for determining the particle size distribution of aggregates.
BS EN 933-3:2012BSI (UK) / CEN (Europe)
HighCurrent
Tests for geometrical properties of aggregates - Part 3: Determination of particle shape - Flakiness index
Specifies the procedure for determining the flakiness index of coarse aggregates.
Key Differences
≠The definition of flakiness and elongation differs. IS 2386 defines a flaky particle as one whose least dimension is less than 0.6 times its mean dimension, and an elongated particle as one whose greatest dimension is more than 1.8 times its mean dimension. In contrast, ASTM D4791 defines these based on a ratio of dimensions (e.g., length to width) where the ratio itself (e.g., 2:1, 3:1) is specified by the user, not fixed in the standard.
≠IS 2386-1 includes a test method for 'Angularity Number,' which determines the angularity of an aggregate based on the percentage of voids in a compacted sample. This specific test is not commonly found in primary ASTM or EN standards, which use other methods like 'Uncompacted Void Content' (ASTM C1252) or 'Flow Coefficient' (EN 933-6) to characterize particle shape and texture.
≠While both IS and ASTM/EN standards use a series of sieves, the standard designated sieve sizes are different. IS 2386 uses a series like 80, 40, 20, 10, 4.75 mm, whereas ASTM C136 uses a series based on inches and their metric equivalents, such as 75 mm (3"), 37.5 mm (1-1/2"), 19.0 mm (3/4"), 9.5 mm (3/8"), and 4.75 mm (No. 4).
≠BS EN 933-4 uses a 'Shape Index' test, which is different from the 'Elongation Index' test in IS 2386. The Shape Index is calculated for individual particles using a caliper and is the ratio of length to thickness, whereas the Elongation Index in IS 2386 is determined in bulk by gauging particles against a length gauge set to 1.8 times the mean dimension of the aggregate fraction.
Key Similarities
≈The fundamental principle of sieve analysis is identical across IS 2386, ASTM C136, and BS EN 933-1: a known mass of aggregate is passed through a nest of sieves with progressively smaller openings, and the mass retained on each sieve is weighed to determine the particle size distribution.
≈All standards (IS 2386, ASTM C136, BS EN 933-1) recognize the 4.75 mm sieve (or its equivalent, the No. 4 sieve in ASTM) as the dividing line between coarse and fine aggregate.
≈The objective of the particle shape tests is the same. IS 2386 (Flakiness/Elongation), ASTM D4791 (Flat/Elongated), and BS EN 933-3 (Flakiness) all aim to quantify and limit the percentage of poorly shaped particles that can negatively impact concrete workability, consolidation, and strength.
≈All standards mandate rigorous sample preparation procedures, requiring that the test sample be representative of the bulk material and be reduced to a testing size using standardized methods like quartering or a mechanical sample splitter to avoid bias.
≈The concept and calculation method for Fineness Modulus of fine aggregate, as a sum of cumulative percentages retained on a specified set of sieves divided by 100, is a common feature in both IS 2386 and ASTM C136, serving as an index of the fineness of the material.