ISO 20290-2:2019

Aggregates for concrete - Test methods for mechanical and physical properties - Part 2: Method for determination of resistance to fragmentation by Los Angeles Test (LA-Test)

This document describes the Los Angeles test, for determining the resistance to fragmentation of coarse aggregates.

Granulats pour béton — Méthodes d'essai relatives aux propriétés mécaniques et physiques — Partie 2: Partie 2: Méthode de détermination de la résistance à la fragmentation par l'essai Los Angeles

General Information

• Status: Published
• Publication Date: 19-Nov-2019
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: ISO/TC 71/SC 1 - Test methods for concrete
• Drafting Committee: ISO/TC 71/SC 1/WG 4 - Test methods for aggregates
• Current Stage: 9093 - International Standard confirmed
• Start Date: 10-Nov-2025
• Completion Date: 13-Dec-2025

Relations

• Revises: ISO 6783:1982 - Coarse aggregates for concrete - Determination of particle density and water absorption - Hydrostatic balance method
• Effective Date: 11-Oct-2014
• Revises: ISO 6274:1982 - Concrete - Sieve analysis of aggregates
• Effective Date: 11-Oct-2014
• Revises: ISO 6782:1982 - Aggregates for concrete - Determination of bulk density
• Effective Date: 11-Oct-2014
• Revises: ISO 7033:1987 - Fine and coarse aggregates for concrete - Determination of the particle mass-per-volume and water absorption - Pycnometer method
• Effective Date: 11-Oct-2014

Overview

ISO 20290-2:2019 specifies the Los Angeles (LA) test method for determining the resistance to fragmentation of coarse aggregates. The standard describes sampling considerations, required apparatus (including the Los Angeles drum and ball load), test portion preparation, the test procedure, calculation of the Los Angeles coefficient (LA) and minimum reporting requirements. This method is widely used in aggregate quality control for concrete, pavements and other civil engineering applications.

Key Topics

• Scope and purpose: Applies to coarse aggregates intended for concrete and allied uses to quantify fragmentation resistance.
• Apparatus: Los Angeles drum (711 ± 5 mm internal diameter, 508 ± 5 mm length), spherical steel balls (11 balls, 45–49 mm diameter; total ~4 690–4 860 g), ventilated oven, sieves conforming to ISO 565, balance with 0.1% accuracy, tray and revolution counter.
• Test portion and grading: Test portion mass (5 000 ± 5 g) prepared from material passing 20 mm and retained on 10 mm sieve, with specified intermediate grading (e.g., 60–70% passing 12.5 mm or 30–40% passing 11.2 mm). Annex A and B provide procedures for larger sizes and alternative narrow-range classifications.
• Procedure: Load the balls and test portion into the drum, seal the opening, and rotate at 30–33 rpm for 500 revolutions (1 000 revolutions and adjusted ball load for larger sizes per Annex A). Recover and sieve the test product, retain material on the 1.6/1.7 mm sieve and dry to constant mass.
• Calculation: The Los Angeles coefficient is calculated from the retained mass (m) using LA = (5000 − m) / 50 (reported to the nearest whole number). For larger aggregates in Annex A the formula is LA = (10000 − m) / 100.
• Test report: Must confirm compliance with ISO 20290-2 and include sample origin, size fractions used, and the LA coefficient.

Applications

• Quality control for concrete aggregates: Use LA values to screen aggregates for susceptibility to mechanical breakdown under action similar to mixing, handling and trafficking.
• Pavement and road construction: Inform selection of coarse aggregates where fragmentation resistance affects durability and skid resistance.
• Material specification and acceptance: Provide a reproducible metric (LA coefficient) for contracts, tender documents and compliance testing.

Related Standards

• ISO 565 - Test sieves (referenced for sieve aperture sizes).
• Other parts of the ISO 20290 series - consult the ISO catalogue for related test methods for mechanical and physical properties of aggregates.

This summary emphasizes the practical steps, apparatus and reporting requirements in ISO 20290-2:2019 for the Los Angeles test. For full normative details, including tolerances, annex procedures for larger sizes, and exact apparatus dimensions, refer to the official ISO 20290-2:2019 document.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 20290-2
First edition
2019-11
Aggregates for concrete — Test
methods for mechanical and physical
properties —
Part 2:
Method for determination of
resistance to fragmentation by Los
Angeles Test (LA-Test)
Granulats pour béton — Méthodes d'essai relatives aux propriétés
mécaniques et physiques —
Partie 2: Partie 2: Méthode de détermination de la résistance à la
fragmentation par l'essai Los Angeles
Reference number
©
ISO 2019
© ISO 2019
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Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Sampling . 2
5 Apparatus . 2
6 Determination of resistance to fragmentation by the Los Angeles test method .3
6.1 Principle . 3
6.2 Preparation of test portion . 3
6.3 Test procedure . 4
6.4 Calculation and expression of results. 4
6.5 Test report . 4
Annex A (normative) Determination of the resistance to fragmentation of aggregates for
larger size aggregates . 5
Annex B (normative) Alternative narrow range classifications for the Los Angeles test .6
Foreword
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bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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electrotechnical standardization.
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described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
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World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 71, Concrete, reinforced concrete and pre-
stressed concrete, Subcommittee SC 1, Test methods for concrete.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
A list of all parts in the ISO 20290 series can be found on the ISO website.
iv © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 20290-2:2019(E)
Aggregates for concrete — Test methods for mechanical
and physical properties —
Part 2:
Method for determination of resistance to fragmentation
by Los Angeles Test (LA-Test)
1 Scope
This document describes the Los Angeles test, for determining the resistance to fragmentation of
coarse aggregates.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 565, Test sieves — Metal wire cloth, perforated metal plate and electroformed sheet — Nominal sizes
of openings
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
Los Angeles coefficient
LA
percentage of the test portion (3.1) passing a pre-determined sieve after completion of the test
3.2
test portion
sample used as a whole in a single test
3.3
laboratory sample
reduced sample derived from a bulk sample for laboratory testing
3.4
constant mass
series of successive weighings after drying at least 1 h apart not differing by more than 0,1 %
Note 1 to entry: In many cases, constant mass can be achieved after a test portion (3.1) has been dried for a
pre-determined period in a specified oven (see 5.1.3) at (105 ± 5) °C. Test laboratories may determine the time
required to achieve constant mass for specific types and sizes of sample dependent on the drying capacity of the
oven used.
4 Sampling
The sample used for the test (the laboratory sample) may be taken in accordance with the procedure
described in the relevant national standards.
5 Apparatus
5.1 General
5.1.1 Test sieves, conforming to ISO 565 or relevant national standards with aperture sizes as 1,6 mm,
10 mm, 11,2 mm (or 12,5 mm), 14 mm and 20 mm.
5.1.2 Balance, capable of weighing the test portion to an accuracy of 0,1 % of the mass of the test
portion.
5.1.3 Ventilated oven, controlled to maintain a temperature of (105 ± 5) °C.
5.1.4 Equipment, for reducing the laboratory sample to a test portion. National standards may be
referred.
5.2 Los Angeles test machine — Figure 1 shows a typical Los Angeles machine.
Key
d internal diameter (711 ± 5) mm
l internal length (508 ± 5) mm
1 shelf
...