ASTM C131/C131M-20 PDF

Full title and description

ASTM C131/C131M‑20 — Standard Test Method for Resistance to Degradation of Small‑Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine. This test method specifies the Los Angeles abrasion (LA abrasion) procedure used to assess the resistance of small‑size coarse aggregates (maximum size less than 37.5 mm / 1½ in.) to abrasion and impact during handling and use in construction materials.

Abstract

Provides the procedure, apparatus description, sample preparation, test conditions, calculation of percent loss, and reporting requirements for determining aggregate resistance to degradation using the Los Angeles testing machine. The test is widely used as an indicator of relative aggregate toughness and suitability for certain pavement and concrete applications; results are comparative and must be interpreted in the context of aggregate type and end use.

General information

• Status: Published / Active.
• Publication date: 15 February 2020 (designation C131/C131M‑20).
• Publisher: ASTM International.
• ICS / categories: 91.100.30 — Concrete and concrete products (aggregates testing).
• Edition / version: C131/C131M‑20 (2020 revision of the C131 series).
• Number of pages: 5 pages (standard text).

Scope

This test method covers the procedure for testing coarse aggregate with a maximum particle size smaller than 37.5 mm (1½ in.) for resistance to degradation by abrasion and impact in the Los Angeles machine. It defines the test charge, machine operation, revolutions, and calculation of percent loss; coarse aggregates larger than 19.0 mm (¾ in.) are also addressed by related Test Method C535, so material in the overlapping size range may be tested by either method.

Key topics and requirements

• Los Angeles machine apparatus description (drum, shelf plate, standard charge of steel balls and aggregate) and proper maintenance.
• Sample preparation and gradings for small‑size coarse aggregate, including drying to substantially constant mass before testing.
• Test conditions: specified charge, machine speed and number of drum revolutions (commonly 500 revolutions at ~30–33 rpm in practice), and procedures for sieving and determining percent loss.
• Calculation and reporting of percent loss (mass loss expressed as percent of original sample mass) and required report elements.
• Unit conventions: values stated in SI units are standard; inch‑pound units are provided for information.
• Notes on interpretation: results are comparative and depend on aggregate mineralogy and source; specification limits should be set with care.

Typical use and users

Used by construction materials laboratories, aggregate producers, quality control personnel, highway agencies, pavement engineers, and concrete technologists to evaluate the abrasion and impact resistance of small‑size coarse aggregates for use in asphalt, concrete, and other construction applications. Training and eLearning on proper execution of C131 are offered for laboratory staff and technicians.

Related standards

Closely related standards and test methods include ASTM C535 (LA abrasion for larger coarse aggregates), AASHTO T96 (equivalent Los Angeles abrasion test procedure used by highway agencies), and regional standards such as EN 1097‑2; equipment and test practice references may also appear in national agency documents.

Keywords

Los Angeles abrasion, LA abrasion, aggregate abrasion, coarse aggregate, percent loss, Los Angeles machine, C131, C131M, AASHTO T96, C535, aggregate toughness, abrasion resistance.

FAQ

Q: What is this standard?

A: ASTM C131/C131M‑20 is the ASTM test method for measuring the resistance to degradation of small‑size coarse aggregate by abrasion and impact using the Los Angeles machine.

Q: What does it cover?

A: It covers apparatus, sample preparation, test procedure (machine charge, revolutions, sieving), calculation of percent loss, and reporting requirements for aggregates with maximum size less than 37.5 mm (1½ in.).

Q: Who typically uses it?

A: Aggregate suppliers, materials testing laboratories, transportation and highway agencies, pavement and concrete engineers, and laboratory technicians responsible for quality control and specifications.

Q: Is it current or superseded?

A: The designation C131/C131M‑20 indicates the 2020 revision; as published it is an active ASTM test method. Users should check for any subsequent revisions or work items that may be in progress. (Revision activity and work items related to C131/C131M have been initiated in the ASTM C09 subcommittee in recent years.)

Q: Is it part of a series?

A: Yes — C131 belongs to the series of ASTM aggregate test methods. It is paired operationally with C535 for larger sizes and is often referenced alongside agency procedures such as AASHTO T96.

Q: What are the key keywords?

A: Los Angeles abrasion, aggregate, abrasion resistance, percent loss, LA machine, coarse aggregate testing, C131, C131M, abrasion and impact.