EN 933-5-1998 pdf download.Tests for gornetrical properties of aggregates Part 5: Determination of percentage of crushed and broken surfaces in coarse aggregate particles.
This European Standard specifics a method for the determination of the percentage of particles with crushed and broken surfaces in a sample of natural coarse aggregate. It applies to gravel or mixed aggregate containing gravel.
The test method specified in this l,art of this European Standard is applicable to particle size fractions dJ1) where 1), ≤ 63 mm and d,  4 mm.
Fl) NOTE 1 For aggregate sizes with I)> 63 mm and/or d < 4 mm the test may he carried out on particle size fracuons dii), where 1).63mmindd,24mm,
NOTE 2 For cuarso aggregate between 4 mm and 20 mm the percentage of crushed or broken surfaces is linked to the flow coefficient and can therefore be used in association with the test method spvvdied in EN 933-6. (]
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references, the latest edition of the publication referred to applies.
prEN 932-2, Tests for general properties of aggregates — Part 2: Methods for reducing laboratory samples. prEN 932-5, Tests for general properties of aggregates Part 5: Common equipment and calibration. EN 933-1, Tests for geomet neal properties of aggregates — Part I: Determination of particle size distribution — Sieving method.
EN 933-2. Tests for geomet neal properties of aggregates — Part 2: Determination of particle size distribution — Test sieves, nominal size of apertures.
3 Definitions
For the purposes of this standard, the following definitions apply.
3.1
aggregate size
a designation of aggregate in terms of lower (d) and upper (0) sieve sizes
NOTF, This designation accepts the presence of some particles which will be retained on the upper sieve (oversize) and some which will pass the lower sieve (undersize).
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particle size fraction dID, fraction of an aggregate passing the larger (0,) of two sieves and retained on the smaller (d)
3.3
test portion
the sample used as a whole in a single test
3.4
constant mass
successive weightings after drying at least I h apart not differing by more than 0,1 %
totally rounded particle
particle with more than 90 % of its surface rounded (tr)
3.9
crushed or broken surfaces
facets of a particle of gravel produced by crushing or broken by natural forces and bounded by sharp edges. Ii If both the surface and the edges of a particle of crushed or broken gravel are worn or weathered then it shall be considered as rounded for the purposes of this test method. (!J
4 Principle
The test consists of sortmg particles by hand. from a test, portion of coarse aggregates into:
— crushed or broken particles, including totally crushed or broken particles;
— rounded particles. including totally rounded particles.
The mass of each of these groups is determined and expressed as a percentage of the test portion mass.
Totally crushed or broken particles and totally rounded particles are then sorted by hand from crushed or broken particles and rounded particles and the mass of these groups is determined and expressed as a percentage of the test portion mass.
5 Apparatus
Unless otherwise stated, all apparatus shall conform to the general requirements of prEN 932.5.
5.1 Test sieves, of nominal size of apertures conforming with EN 933-2.
5.2 Tightly fitting pan and lid, for the sieves.
5.3 Ventilated oven, thermostaticafly controlled to maintain a temperature of (110± 5) °C or equipment for drying the aggregate which does not cause any particle size breakdown.
5.4 Balance or scale, of suitable capacity. readable to ±0.1 % of the mass to be weighed.
5.5 Trays.
5.6 Brushes.
5.7 Sieving machine, optional.
6 Preparation of test portion
The sample shall be reduced in accordance with the requirements of prEN 932.2.
Dry the sample at (110 ± 5) DC La constant mass, Weigh and record the mass as M0
Sieve on appropriate test sieves agitating with sufficient vigour to ensure complete separation of particles greater than 4 mm. Discard the particles retained on the 63 mm test sieve and those passing the 4 mm test sieve.
If necessary further reduce the sample in accordance with prEN 932.2 to produce a test Portion. Record the mass of the test portion as M1. The mass of the test portion shall be as specified in Table 1.EN 933-5-1998 pdf download.