⛰️ Sieve Analysis of Aggregate

Construction PN-EN 933-1

Overview

STATUS (as of 28.10.2026). PN-EN 933-1:2012 — English version, published 19.03.2012, implements EN 933-1:2012 [IDT]; it replaced PN-EN 933-1:2000 and PN-EN 933-1:2000/A1:2006 (Polish versions). The standard is current — no withdrawal note.

SCOPE (clause 1). The standard describes the reference method — washing and dry sieving — used for type testing and in case of dispute. For other purposes, in particular factory production control, other methods may be used provided that their relationship with the reference method has been established. The method applies to all aggregates, including lightweight aggregates, up to 90 mm nominal size, except fillers — their grading is determined according to PN-EN 933-10 (air jet sieving). Aggregates free from particles that cause agglomeration may be dry sieved without washing.

PRINCIPLE (clause 4). The material is divided into several particle size classes on a set of sieves of decreasing aperture sizes. The number of sieves and their aperture sizes are chosen according to the nature of the sample and the accuracy required — the standard does not impose a single set. When washing could change the physical properties of a lightweight aggregate, only dry sieving is used. The masses retained on the sieves are related to the initial dry mass of the sample.

SIEVES (5.1 and 7.2). Nominal aperture sizes according to PN-EN 933-2, sieves conforming to ISO 3310-1 and ISO 3310-2. PN-EN 933-2 gives apertures from 0.063 to 125 mm: below 4 mm — metal wire cloth sieves, from 4 mm — perforated metal plate with square holes. The 0.063 mm sieve must be included in the column even after washing, because washing does not always remove all fines.

TEST PORTION MASS (clause 6, Table 1). The minimum mass of the test portion depends on the aggregate size D: 80 kg for D = 90 mm, 10 kg for 32 mm, 2.6 kg for 16 mm, 0.6 kg for 8 mm and 0.2 kg for D ≤ 4 mm; for other sizes below 90 mm the mass may be interpolated with M = (D/10)² kg. For lightweight aggregates according to PN-EN 13055 the volume column applies (from 0.3 l for D ≤ 4 mm to 2.1 l for D = 32 mm), and for aggregates with particle density above 3.00 Mg/m³ the mass is corrected by the density ratio. A smaller test portion may reduce precision — its size is then given in the test report. Sample reduction should yield a test portion larger than the minimum, not one of an exact predetermined size.

DRYING (3.3, clause 6, 7.1). The test portion and the residue after washing are dried at (110 ± 5) °C to constant mass, i.e. until successive weighings at least 1 h apart do not differ by more than 0.1 %. The laboratory may determine the drying time needed to reach constant mass for a given type and size of sample and oven. When drying at 110 °C binds particles so that they cannot be separated, the procedure of normative Annex B is used; for all-in aggregates with D ≥ 31.5 mm the procedure of Annex A may be used.

END OF SIEVING AND SIEVE OVERLOADING (7.2). Sieving is considered complete when further sieving does not change the mass retained on any sieve by more than 1.0 %; depending on the aggregate it may be considered complete when the mass does not change by more than 1.0 % within 1 min. The standard does not specify a shaker time: the effectiveness of mechanical sieving depends on the aggregate type, the sieving time, the sieve loading and the amplitude and frequency of the motion, so the time has to be chosen. The mass of normal-weight aggregate retained on a sieve should not exceed A × √d / 200 grams (A — sieve area in mm², d — aperture size in mm).

VALIDITY AND PRECISION (8.2 and 8.3). If the sum of the masses retained on the sieves (Ri) and of the material in the pan (P) differs by more than 1 % from mass M2 — the dried residue after washing — the test is repeated. For sieves from 0.063 to 4 mm the standard gives repeatability r1 = 0.042·√[X·(100 − X)] and reproducibility R1 = 0.086·√[X·(100 − X)], where X is the mean cumulative percentage passing the sieve; the data come from an interlaboratory test on 0/0.4 and 0/2 mm sands (17 laboratories from 9 countries). Precision strongly depends on sieve loading — overloaded sieves degrade it.

ASSESSMENT OF THE RESULT. The test standard contains no requirements. Categories of grading and fines content (e.g. Gc85/20 for coarse aggregate, GF85 for fine aggregate, GA85 for all-in aggregate, f for fines) are set by product standards — PN-EN 12620 (aggregates for concrete), PN-EN 13043 (aggregates for bituminous mixtures and surface treatments), PN-EN 13242 (aggregates for unbound and hydraulically bound materials) — and the manufacturer declares them in the declaration of performance.

WHAT WE DO NOT GIVE HERE. The procedures of Annex A (all-in aggregates, D ≥ 31.5 mm) and Annex B (aggregates unsuitable for oven drying) — we only know their purpose and clause titles. The standard does not give durations of the individual steps and we do not state them here.

Method principle

A test portion with a mass not less than in Table 1 is dried at (110 ± 5) °C to constant mass and weighed (M1). It is then covered with water, the fines are brought into suspension and the portion is washed on a 0.063 mm sieve protected by a guard sieve until the water passing the sieve is clear; the residue is dried to constant mass and weighed (M2). Lightweight aggregates whose properties are changed by water are dry sieved without washing; aggregates without agglomerating particles may be sieved this way.

The dried material is sieved on a column of sieves of decreasing aperture size with pan and lid, manually or mechanically, and then with each sieve separately, until further sieving does not change the retained mass by more than 1.0 %. The material retained on the sieves (Ri) and in the pan (P) is weighed; the results are the cumulative percentages of M1 passing each sieve and the fines content f = [(M1 − M2) + P] / M1 × 100. The test is repeated if the sum of Ri and P differs from M2 by more than 1 %.

Applications

• Type testing and settling disputes on the grading of aggregates — PN-EN 933-1 is the reference method
• Factory production control of aggregates — with this method or another one whose relationship with the reference method has been established
• Grading and fines content declared for aggregates for concrete, bituminous mixtures and unbound materials — categories from PN-EN 12620, PN-EN 13043 and PN-EN 13242 (e.g. Gc85/20, GF85, GA85)
• Lightweight aggregates according to PN-EN 13055 — test portion from the volume column; without washing when water changes their properties

Key parameters

Standard

Standard number

PN-EN 933-1:2012

Title (PL)

Badania geometrycznych właściwości kruszyw — Część 1: Oznaczanie składu ziarnowego — Metoda przesiewania

Title (EN)

Tests for geometrical properties of aggregates — Part 1: Determination of particle size distribution — Sieving method

Step-by-step procedure

1. Reducing the laboratory sample

   Sampling — according to PN-EN 932-1. The laboratory sample is reduced according to PN-EN 932-2 to the required number of test portions; each has a mass not less than in Table 1 (not adjusted exactly to a predetermined value). Samples with a large amount of fines may be moistened before reduction to limit segregation and loss of dust (clause 6).

2. Drying and weighing the test portion

   Dry at (110 ± 5) °C to constant mass, cool, weigh to ±0.1 % of the test portion mass and record mass M1. When drying at 110 °C binds the particles — apply the procedure of Annex B of the standard (clause 6).

   🌡 Temperature: 110 ± 5 °C

3. Covering with water and dispersing the fines

   Cover the test portion in a container with water and agitate vigorously enough to separate the fines completely and bring them into suspension. Keeping the portion under water for 24 h helps to break down lumps; a dispersing agent may be added (7.1). Lightweight aggregates whose properties are changed by water are dry sieved, without steps 3–5; aggregates without agglomerating particles may be sieved this way (clause 1, Note 2).

4. Washing on the 0.063 mm sieve with a guard sieve

   Wet both sides of the 0.063 mm sieve reserved for this test only and fit a guard sieve (e.g. 1 mm or 2 mm) on top. Pour the contents of the container onto the top sieve and continue washing until the water passing the 0.063 mm sieve is clear. Do not overload, overflow or damage the sieves; with some aggregates only the suspended fines are poured first and the coarse residue is washed further in the container (7.1).

5. Drying the residue after washing

   Dry the residue on the 0.063 mm sieve at (110 ± 5) °C to constant mass, cool, weigh and record mass M2 (7.1).

   🌡 Temperature: 110 ± 5 °C

6. Sieving on the column

   Pour the washed and dried material (or the dry test portion) into the column of sieves arranged from the top in order of decreasing aperture sizes, with pan and lid; the 0.063 mm sieve must be in the column. Shake the column manually or mechanically, then remove the sieves one by one, starting with the largest aperture, and shake each by hand with pan and lid, transferring everything that passes onto the next sieve (7.2).

7. Checking overloading and the end of sieving

   The mass of normal-weight aggregate on a sieve should not exceed A × √d / 200 g; if overloaded, sieve the fraction in portions or reduce the part passing the next larger sieve and allow for it in the calculations. Sieving ends when further sieving does not change the mass on any sieve by more than 1.0 % (depending on the aggregate — within 1 min). For lightweight aggregates no more than one layer of particles should remain on a sieve (7.2).

8. Weighing the retained material

   Weigh the material retained on the sieve with the largest aperture (R1), on the following sieves (R2 … Rn) and in the pan (P) (7.3).

9. Calculation and validity of the result

   Calculate the material retained on each sieve as a percentage of M1, and the cumulative percentage passing — for each sieve down to 0.063 mm exclusive. Fines content: f = [(M1 − M2) + P] / M1 × 100; for dry sieving f = 100 · P / M1. If the sum of Ri and P differs from M2 by more than 1 %, repeat the test (clause 8).

10. Test report

    State at least: reference to the standard, identification of the sample and of the laboratory, sample reception date, method (washing and sieving or dry sieving) and the cumulative percentages passing — for the 0.063 mm sieve to 0.1, for the other sieves to a whole number. A graph (Annex D), the sample source and description of the material, and the reduction procedure are optional data (clause 9).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• The standard contains no safety requirements — protective measures are set by the laboratory on the basis of a risk assessment
• The oven runs at (110 ± 5) °C — remove trays and samples with heat-protective gloves
• Samples can be heavy: the minimum mass is 10 kg for D = 32 mm and 80 kg for D = 90 mm (Table 1) — this must be taken into account when moving them and choosing equipment
• Dry sieving generates dust — sieve with pan and lid and clean the sieves without spreading dust

Frequently asked questions