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The aggregates used in the production of concrete are inert granular materials such as gravel, crushed stone, sand, slag, recycled concrete, and geosynthetic aggregates. The aggregates may be natural, manufactured, or recycled.

This article is in continuation of the article: Geometrical Requirement of Aggregates as per European Standards [PDF].

In this article, we discuss the physical requirement of the aggregates such as resistance to fragmentation, wear, polishing, abrasion, particle density, bulk density, and durability used in the production of concrete as per the European Standards (EN – 12620).

1. Resistance to Fragmentation of Coarse Aggregate

The resistance to fragmentation shall be determined with the Los Angeles test method as a reference in terms of the Los Angeles coefficient, as specified in EN 1097-2:1998, clause 5.

The obtained Los Angeles coefficient shall be declared in accordance with the relevant category specified in Table 12, according to the particular application or end-use.

Table 12 – Categories for maximum values of Los Angeles coefficients

Categories for maximum values of Los Angeles coefficients

Where required, the impact value determined in accordance with EN 1097-2:1998, clause 6, shall be declared in accordance with the relevant category specified in Table 13 according to the particular application or end-use.

Table 13: Categories for maximum values of resistance to impact

Catergories for maximum values of resitance to impact

2. Resistance to Wear of Coarse Aggregate

The resistance to wear of coarse aggregate shall be determined in accordance with EN 1097-1. The micro-deval coefficient shall be declared in accordance with the relevant categories specified in Table 14, according to the particular application or end-use.

Table 14: Categories of maximum values of resistance to wear

Categories of maximum values of resistance to wear

3. Resistance to Polishing

The resistance to polishing of coarse aggregate to be used for surface courses (polished stone value-PSV) shall be determined in accordance with EN 1097-8. The resistance to polishing shall be declared in accordance with the relevant category specified in Table 15.

Table 15 – Categories for minimum values of resistance to polishing

Categories for minimum values of resistance to polishing

4. Resistance to Surface Abrasion

The resistance to surface abrasion (aggregate abrasion value – AAV), shall be determined in accordance with EN 1097-8:1999, annex A. The resistance to surface abrasion shall be declared in accordance with the relevant category specified in Table 16.

Table 16: Categories for maximum values of resistance to surface abrasion

When required the resistance to surface abrasion (aggregate abrasion value - AAV), shall be determined in accordance with EN 1097-8:1999, annex A.  The resistance to surface abrasion shall be declared in accordance with the relevant category specified in Table 16.  Table 16  Categories for maximum values of resistance to surface abrasion

5. Resistance to Abrasion from Studded Tires

The resistance to abrasion from studded tires (Nordic abrasion value- An), shall be determined in accordance with EN 1097-9. Resistance to abrasion from studded tires shall be declared in accordance with the relevant category specified in Table 17.

Table 17 – Categories for maximum values of resistance to abrasion from studded tires

Categories for maximum values of resistance to abrasion from studded tyres

6. Particle Density and Water Absorption

The particle density and water absorption shall be determined in accordance with EN 1097-6, and the results declared on request stating the means of determination and the calculations used.

7. Bulk Density

When required, the bulk density shall be determined in accordance with EN 1097-3, and the results declared on request.

8. Durability

8.1 Freeze and Thaw Resistance of Coarse Aggregate

The aggregates used in the environment subjected to freezing and thawing shall be tested in accordance with EN 1367-1 or EN 1367-2, respectively, in accordance with the relevant category specified in Table 18 or Table 19.

Table 18: Categories of maximum values of freeze-thaw resistance.

Catergories of maximum values of freeze-thaw resistance.

Table 19: Categories of maximum Magnesium sulfate soundness

Catergories of maximum Magnesium sulfate soundness

8.2 Volume Stability – Drying Shrinkage

In case where disruptive shrinkage cracking of concrete occurs due to the properties of the aggregate, the drying shrinkage associated with aggregates to be used in structural concrete shall, when required, not exceed 0,075 % when tested in accordance with EN 1367-4 and the results declared.

8.3 Alkali-Silica Reactivity

When required, the alkali-silica reactivity of aggregates shall be assessed in accordance with the provisions valid in the place of use, and the results declared.

1. What is the importance of aggregates in concrete?

The properties of concrete such as workability, durability, strength, weight, and, shrinkage are governed by the properties (composition, shape, and size) of aggregate used in the concrete.

2. Which size of coarse aggregate is commonly used in the production of concrete?

Commonly, aggregate passing the sieve of 20mm and retaining the sieve of 12.5mm is preferred for the production of concrete.

Read More
1. Geometrical Requirement of Aggregates as per European Standards
2. Aggregates for Concrete as per American Standards – ASTM

Fasi Ur Rahman

Fasi Ur Rahman

EDITOR
Fasi is a Civil Engineer associated with Project Management Consultant for Tumkur Smart City Project in Karnataka, India. He is the author, editor, and partner at theconstructor.org

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