⛰️ Aggregate sand equivalent

Construction PN-EN 933-8

Overview

STATUS (as of 06.11.2026). PN-EN 933-8+A1:2015-07 — English version, published on 22.07.2015, implements EN 933-8:2012+A1:2015 [IDT]; it replaced PN-EN 933-8:2012 (English version). The PKN card has no withdrawal note — the standard is current. It is a complete consolidated document of the 2012 edition with Amendment A1 approved by CEN on 19.04.2015.

SCOPE (clause 1). The standard describes the reference method — for type testing and in case of dispute — for determining the sand equivalent value of the 0/2 mm fraction in fine aggregates or all-in aggregates (0/4 mm fraction — Annex A). For other purposes, in particular factory production control, other methods may be used provided that an appropriate working relationship with the reference method has been established. Fines are the fraction passing the 0.063 mm sieve (3.1).

PRINCIPLE (clause 4). A 0/2 mm test specimen with a fines content of at most 10 % (natural or after grading curve adjustment) and a small quantity of washing and flocculating solution are poured into a graduated cylinder and agitated to loosen the clay coatings from the coarser particles. The aggregate is then irrigated with additional solution, forcing the fine particles into suspension. After a fixed time, the sand equivalent value SE(10) is calculated as the height of sediment expressed as a percentage of the total height of sediment and suspension in the cylinder. The foreword of the 2012 edition explains that it differs from the 1999 edition in that the fines content of the 0/2 mm fraction is limited to 10 %.

REAGENTS (clause 5). Concentrated solution: (219 ± 2) g of crystalline calcium chloride CaCl₂·6H₂O (equivalent to 111 g of anhydrous CaCl₂) is dissolved in (350 ± 50) ml of distilled or demineralised water, cooled and filtered if necessary, (480 ± 5) g of glycerine (99 % glycerol) and (12.5 ± 0.5) g of formaldehyde solution, 40 % by volume, are added, and the solution is diluted with water to 1 l. It is recommended to store it protected from light in flasks containing (125 ± 1) ml. Sodium hypochlorite with 2.6 % active chlorine can be used instead of formaldehyde, but formaldehyde is used in case of dispute. Washing and flocculating solution: (125 ± 1) ml of concentrated solution diluted with water to (5.00 ± 0.01) l; it is not used more than 28 days after preparation or if it is cloudy or contains a precipitate or mould.

APPARATUS (clause 6). Two graduated cylinders of glass or clear plastic: inside diameter (32.0 ± 0.5) mm, height (430.00 ± 0.25) mm, marks at (100.00 ± 0.25) mm and (380.00 ± 0.25) mm from the base. Test plunger: rod (440.00 ± 0.25) mm, end piece (25.0 ± 0.1) mm in diameter with three guides, collar (10.0 ± 0.1) mm with a locking screw and a slot for a rule, mass of the assembly excluding the collar (1.00 ± 0.01) kg, immersed parts of non-corrodible metal. Stop clock readable to 1 s, 500 mm rule graduated in millimetres, 0.063 mm and 2 mm sieves according to EN 933-2, washing tube with an outside diameter of (6.0 ± 0.5) mm with a tap and two (1 ± 0.1) mm holes in the tip, 5 l flask with a siphon about 1 m above the bench, tube about 1.5 m long, funnel.

PROCEDURE — SECOND SOURCE. Clauses 7–9 of the standard (preparation of test specimens, filling, shaking, washing, measurements, calculation) are outside the available text. The operating instructions of a sand equivalent apparatus manufacturer (ELE International, 2016) describe the procedure as follows: solution to the 10 cm mark, test portion poured in with a funnel, 10 min rest, 90 shaking cycles in 30 s (by hand with a stroke of about 20 cm, or with a mechanical shaker), irrigation with the tube from the bottom until the level reaches the 38 cm mark, 20 min rest without vibration, reading of the suspension height H, lowering of the plunger onto the sediment and reading of the sediment height h; value = 100 · h / H. These instructions call for the mean of at least three determinations, whereas the standard provides two cylinders — the number of determinations and permitted differences are taken from the standard.

WHAT WE DO NOT GIVE HERE. Test portion mass, time tolerances, rounding and precision — they are in clauses 7–9 of the standard, outside the available text. Requirements for the sand equivalent value for particular uses of aggregates — they are not in the test standard.

Method principle

A test specimen of the 0/2 mm fraction (fines content at most 10 %) with a small quantity of washing and flocculating solution (calcium chloride, glycerine, formaldehyde) is placed in a graduated cylinder and agitated to loosen the clay coatings from the particles, then irrigated with solution from the bottom, forcing the fine particles into suspension. After a fixed settling time, the total height of sediment and suspension and the height of the sediment alone (with a plunger of 1 kg mass) are measured. The sand equivalent value SE(10) is the height of sediment expressed as a percentage of the total height.

Applications

• Reference method for type testing and in case of dispute — 0/2 mm fraction of fine aggregates or all-in aggregates (clause 1)
• 0/4 mm fraction — according to Annex A of the standard (clause 1)
• Factory production control — other methods too, if their relationship with the reference method has been established (clause 1)
• Assessment of fines in aggregates alongside the methylene blue test (EN 933-9) — EN 933 series (foreword)

Key parameters

Standard

Standard number

PN-EN 933-8+A1:2015-07 (English version; adopts EN 933-8:2012+A1:2015 [IDT])

Title (PL)

Badania geometrycznych właściwości kruszyw — Część 8: Ocena zawartości drobnych cząstek — Badanie wskaźnika piaskowego

Title (EN)

Tests for geometrical properties of aggregates — Part 8: Assessment of fines — Sand equivalent test

Step-by-step procedure

1. Concentrated solution

   Dissolve (219 ± 2) g of CaCl₂·6H₂O in (350 ± 50) ml of water, cool and filter if necessary; add (480 ± 5) g of glycerine and (12.5 ± 0.5) g of formaldehyde solution, dilute with water to 1 l and mix (5.1).

2. Washing and flocculating solution

   Dilute (125 ± 1) ml of concentrated solution with water to (5.00 ± 0.01) l; do not use after 28 days or if cloudy or containing a precipitate (5.2).

3. Test specimen

   Prepare a 0/2 mm test specimen with a fines content of at most 10 % in accordance with clause 7 of the standard (reduction according to EN 932-2, sieving according to EN 933-1).

4. Filling the cylinder

   Pour solution to the 100 mm mark and add the test specimen with the funnel (clause 8; apparatus manufacturer instructions).

5. Rest and shaking

   According to the apparatus manufacturer instructions: 10 min rest, then 90 shaking cycles in 30 s (by hand or with a shaker).

6. Irrigation

   Irrigate the sediment from the bottom with the washing tube until the solution level reaches the 380 mm mark (clause 8; apparatus manufacturer instructions).

7. Sedimentation and readings

   According to the apparatus manufacturer instructions: after 20 min without vibration read the total height of sediment and suspension, lower the plunger onto the sediment and read the sediment height.

8. Calculation

   SE(10) = height of sediment / total height of sediment and suspension × 100 (clause 4); expression of the result and number of determinations according to clause 9 of the standard.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Formaldehyde solution — harmonised CLP classification including H350 (may cause cancer), H330 (fatal if inhaled), H314, H317, H341; prepare the concentrated solution under an extraction hood wearing gloves and goggles
• Calcium chloride — H319 (causes serious eye irritation, harmonised CLP classification)
• The standard contains no other safety requirements; working rules are set by the laboratory on the basis of a risk assessment

Frequently asked questions