🧱 Cement Strength

Construction PN-EN 196-1

Overview

STATUS (as of 02.11.2026). PN-EN 196-1:2016-07 — Polish version, published 12.01.2018, implements EN 196-1:2016 [IDT]; it replaced PN-EN 196-1:2006. The card has no withdrawal note — the standard is current; in the catalogue of European standards (iTeh), EN 196-1:2016 is at stage 90.92 — after review it was decided to revise it. Compared with the 2005 edition, the 2016 edition updated the normative references, the precision data for compressive strength (repeatability and reproducibility also at 2 and 7 days) and the mixing procedure (an indication of the maximum time for adding the constituents to the bowl).

SCOPE (clause 1). The standard describes the determination of the compressive and, optionally, the flexural strength of cement mortar. It applies to common cements and to other cements and materials whose standards call up this method; it may not apply to some cements, e.g. with a very short initial setting time. The method is used for assessing whether the compressive strength of cement conforms to its specification, and for validation testing of CEN standard sand and alternative compaction equipment. The standard describes the reference equipment and procedure; alternatives may be used after validation in accordance with its provisions, but in a dispute only the reference ones are used.

PRINCIPLE (clause 3). Prisms 40 mm × 40 mm × 160 mm are cast from plastic mortar of one part by mass of cement, three parts by mass of CEN standard sand and one half part of water (w/c 0.50). CEN standard sands from various sources and countries may be used provided they give results that do not differ significantly from those obtained with the CEN reference sand (clause 11). In the reference procedure, the mortar is mixed mechanically and compacted in a mould on a jolting apparatus. The specimens are stored in the mould in a moist atmosphere for 24 h and, after demoulding, in water until testing. At the required age, the prisms are broken in flexure (determining the flexural strength where required) or by other means that do not harm the halves, and each half is tested in compression.

LABORATORY (4.1). Room for preparing specimens: (20 ± 2) °C, relative humidity of at least 50 %. Moist air room or large cabinet for storing specimens in moulds: (20.0 ± 1.0) °C, humidity of at least 90 %. Water in the curing containers: (20.0 ± 1.0) °C, containers and grates of material that does not react with cement. The air temperature and humidity in the laboratory and the water temperature are recorded at least once a day during working hours, and the temperature and humidity of the moist air room or cabinet at least every 4 h. Cement, sand, water and apparatus are at (20 ± 2) °C.

APPARATUS (4.3–4.5; other equipment — according to a laboratory instruction of the Rzeszów University of Technology). Wire cloth sieves with apertures of 2.00; 1.60; 1.00; 0.50; 0.16 and 0.08 mm. Mixer with a stainless steel bowl of about 5 l and a blade in planetary movement, with a gap of (3 ± 1) mm between blade and bowl; speeds: low — (140 ± 5) min⁻¹ rotation and (62 ± 5) min⁻¹ planetary movement, high — (285 ± 10) and (125 ± 10) min⁻¹. Steel mould with three compartments, internal dimensions of a compartment: length (160 ± 1) mm, width (40.0 ± 0.2) mm, depth (40.1 ± 0.1) mm, internal faces with a hardness of at least HV 200 (HV 400 recommended), with a baseplate, a hopper, two spreaders and a straightedge; the outer joints of the mould are sealed and the internal faces coated with a thin film of mould oil (mineral oils have been found suitable). According to the Rzeszów University of Technology instruction, the jolting apparatus gives 1 jolt per second and 60 jolts per layer with a lift of (15 ± 0.3) mm, the flexural device has supports (100 ± 0.5) mm apart and the compression press a jig with 40 mm × 40 mm platens; the force is measured with an error of not more than 1 %, masses are weighed to 1 g and water is measured to 1 ml.

MORTAR AND PRISMS (according to the Rzeszów University of Technology instruction). Per mould: (450 ± 2) g of cement, (1350 ± 5) g of standard sand (usually in bags of 1350 g) and (225 ± 1) ml of water. Water is poured into the bowl, cement is added and mixed for 30 s at low speed, sand is added during the next 30 s, mixing continues for 30 s at high speed, during a 90 s stop the mortar is scraped from the walls to the centre of the bowl, and mixing continues for another 60 s at high speed. The mould with its hopper is fixed to the jolting apparatus, filled in two layers (the first about 300 g per compartment), each compacted with 60 jolts; the surplus is removed with the straightedge in a sawing motion and the surface is smoothed. The mould, covered with a glass or steel plate, is stored horizontally in the moist air room; the prisms are demoulded after 20–24 h (for testing at 24 h — not more than 20 min before testing), marked and placed on a grate in water at (20.0 ± 1.0) °C, with spacing between prisms, from the walls and from the water surface greater than 5 mm.

TESTING AND RESULT (according to the Rzeszów University of Technology instruction). A prism taken out of the water and dried is placed on its side on the supports and loaded at mid-span with a force increase of (50 ± 10) N/s until fracture; Rf = 1.5 · Ff · l / b³ (l — distance between supports, b — side of the section). The halves are compressed between 40 mm × 40 mm platens with a force increase of (2400 ± 200) N/s until failure; Rc = Fc / 1600 (Fc in N, result in MPa). The result is the mean of six compressive strength values from three prisms; if one of them differs from the mean by more than 10 %, it is discarded and the mean of five is calculated, and if one of these five again differs by more than 10 %, the whole result is discarded. Results are given to 0.1 MPa.

REQUIREMENTS FOR CEMENT (PN-EN 197-1:2012 — according to a document by a cement producer). Standard strength at 28 days: class 32.5 — from 32.5 MPa to 52.5 MPa, class 42.5 — from 42.5 MPa to 62.5 MPa, class 52.5 — at least 52.5 MPa. Early strength (at least): 32.5 L — 12.0 MPa at 7 days, 32.5 N — 16.0 MPa at 7 days, 32.5 R — 10.0 MPa at 2 days; 42.5 L — 16.0 MPa at 7 days, 42.5 N — 10.0 MPa at 2 days, 42.5 R — 20.0 MPa at 2 days; 52.5 L — 10.0 MPa at 2 days, 52.5 N — 20.0 MPa at 2 days, 52.5 R — 30.0 MPa at 2 days. The letter L (low early strength) applies only to blast furnace cement CEM III, N — ordinary, R — high early strength. PN-EN 197-1:2012 (Polish version, published 14.10.2013, implements EN 197-1:2011) — card without a withdrawal note.

WHAT WE DO NOT GIVE HERE. The requirements of the standard for the jolting apparatus, flexural device, compression machine with jig, balance and timer (4.6–4.11), the requirements for CEN standard sand, cement and water (clause 5), the tolerances on the age of specimens (8.4), the precision data (10.2.3) and the validation of sand and alternative equipment (clause 11) — the available text of the standard ends at 4.5; the mixing, moulding and testing procedure is given according to a university instruction based on this standard.

Method principle

From standard mortar (450 g cement, 1350 g CEN standard sand, 225 g water; w/c 0.50), mixed mechanically according to a fixed programme and compacted on a jolting apparatus in a three-compartment mould, three prisms 40 mm × 40 mm × 160 mm are made. They are stored in the mould in moist air at (20.0 ± 1.0) °C for 24 h and, after demoulding, in water at (20.0 ± 1.0) °C. At the required age they are broken in flexure on supports 100 mm apart (force increase (50 ± 10) N/s; Rf = 1.5 · Ff · l / b³), and the halves are compressed between 40 mm × 40 mm platens (force increase (2400 ± 200) N/s; Rc = Fc / 1600). The result is the mean of six compressive strength values.

Applications

• Assessment of the conformity of the compressive strength of cement with its specification (scope of the standard)
• Common cements according to EN 197-1 — classes 32.5, 42.5 and 52.5 with early strength L, N or R
• Other cements and materials whose standards call up EN 196-1
• Validation of CEN standard sand and alternative compaction equipment (clause 11)
• Disputes — settled only with the reference equipment and procedure

Key parameters

Standard

Standard number

PN-EN 196-1:2016-07

Title (PL)

Metody badania cementu — Część 1: Oznaczanie wytrzymałości

Title (EN)

Methods of testing cement — Part 1: Determination of strength

Step-by-step procedure

1. Conditions and materials

   Laboratory at (20 ± 2) °C, humidity of at least 50 %; cement, sand, water and apparatus at (20 ± 2) °C. Weigh (450 ± 2) g of cement and (1350 ± 5) g of sand, measure (225 ± 1) ml of water (4.1; university instruction).

   🌡 Temperature: 20 ± 2 °C

2. Preparing the mould

   Clean the mould, assemble it with the baseplate, seal the outer joints, coat the internal faces with a thin film of mould oil; fix the mould with its hopper to the jolting apparatus (4.5; university instruction).

3. Mixing

   Pour in the water, add the cement; mix for 30 s at low speed, add the sand during the next 30 s, mix for 30 s at high speed, during a 90 s stop scrape the mortar from the walls to the centre of the bowl, mix for 60 s at high speed (university instruction; mixer — 4.4).

4. Moulding

   Fill the compartments with the first layer (about 300 g per compartment), spread and compact with 60 jolts; add the second layer and again compact with 60 jolts. Remove the hopper, strike off the surplus with the straightedge in a sawing motion, smooth the surface (university instruction).

5. Storage in the mould

   Store the mould, covered with a glass or steel plate, horizontally in the moist air room at (20.0 ± 1.0) °C and a humidity of at least 90 % (4.1, clause 3; university instruction).

   🌡 Temperature: 20.0 ± 1.0 °C

6. Demoulding

   Demould after 20–24 h (prisms for testing at 24 h — not more than 20 min before testing) and mark them permanently (university instruction).

7. Curing in water

   Place the prisms on a grate in water at (20.0 ± 1.0) °C, with spacing between prisms, from the walls and from the water surface greater than 5 mm; keep in water until testing (4.1; university instruction).

   🌡 Temperature: 20.0 ± 1.0 °C

8. Flexure

   At the required age take out a prism, dry it, place it on its side on supports 100 mm apart and load at mid-span with a force increase of (50 ± 10) N/s until fracture; Rf = 1.5 · Ff · l / b³ (university instruction).

9. Compression

   Place the halves between 40 mm × 40 mm platens (the surface smoothed with the straightedge — vertical) and compress with a force increase of (2400 ± 200) N/s until failure; Rc = Fc / 1600 (university instruction).

10. Result

    Mean of six compressive strength values; discard a value differing from the mean by more than 10 % and calculate the mean of five, and with a second such value discard the whole result. Give the results to 0.1 MPa (university instruction).

11. Assessment

    Compare the result with the specification of the cement — for EN 197-1 with the standard strength at 28 days and the early strength at 2 or 7 days according to the class (32.5 / 42.5 / 52.5 with the letter L, N or R).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• The available text of the standard contains no safety requirements — rules for working with cement (according to its safety data sheet) and with the press are set by the laboratory on the basis of a risk assessment

Frequently asked questions