🛣️ Determination of the compressive strength of specimens of hydraulically bound mixtures (bases, improved subgrade layers, cement-stabilized soils) — cylindrical or cubical specimens manufactured in the laboratory or taken as cores, compressed uniaxially without packing with a load increase giving failure within 30–120 s; Rc = F/Ac in N/mm², assessment of the type of failure, PN-EN 13286-41

Construction PN-EN 13286-41

Overview

WHAT THE STANDARD COVERS. Scope from the PKN catalogue card of PN-EN 13286-41:2022-04 (English version), in full (here in the wording of EN 13286-41:2021, Clause 1): “This document describes a test method for the determination of the compressive strength of specimens of hydraulically bound mixtures. This document applies to specimens manufactured in the laboratory or prepared from cores”. We read the text of the standard in the sample of SIST EN 13286-41:2022 (the text of EN 13286-41:2021 without changes) from the cover to 9.1 (compulsory information of the test report) up to item l) inclusive. We do not have Figures 1–4 (failure patterns of cubes and cylinders), the rest of 9.1 or 9.2.

ACCORDING TO THE TEXT OF EN 13286-41:2021 (foreword, Clauses 1–9.1 l)). The standard was prepared by CEN/TC 227 “Road materials” (secretariat BSI); approved by CEN on 5 July 2021, it supersedes EN 13286-41:2003. Changes from the 2003 edition (foreword): editorial changes and — to cater for the wide range of strengths possible for hydraulically bound mixtures, from below 1 MPa to 50 MPa or more — an increase in the permitted “time window” for rupture of the specimen. The EN 13286 series covers among others laboratory reference density and water content (Parts 1–5), direct (40) and indirect (42) tensile strength, modulus of elasticity (43), California bearing ratio (47), manufacture of specimens by Proctor equipment or vibrating table (50), vibrating hammer (51), vibrocompression (52) and axial compression (53). Scope (1) — as on the card. References (2): EN 12390-3:2019 (compressive strength of concrete specimens), EN 13286-50, -51, -52 and -53. Terms (3): hydraulically bound mixture — mixture that hardens by hydraulic, pozzolanic, sulfatic or carbonatic reaction, usually with a workability suited to compaction by rolling, generally used in bases, sub-bases and capping layers; compressive strength — stress at failure of a specimen tested in uniaxial unconfined compression; slenderness ratio — ratio of length to diameter of a cylindrical specimen. Principle (4): the specimen is subjected to a compressive force until failure, the maximum load sustained is recorded and the compressive strength calculated. Apparatus (5.1): compression testing machine capable of loading and measurement to an accuracy of ± 1 %; Note 1 — specimens may be cylindrical or cubical, with nominal dimensions from 50 mm (diameter) to 300 mm (height) and strengths from 0,5 N/mm² to normal concrete strengths; machines according to EN 12390-4 can be suitable for stronger specimens; two steel loading platens with a surface hardness of at least 55 HRC to a depth of about 5 mm, at least as large as (preferably larger than) the specimen faces, with a flatness of 0,03 mm or better (Note 2 — auxiliary platens at least 25 mm thick meeting the same requirements may be used); upper platen with a spherical seating whose centre lies at the platen surface or less than 1 mm from it, of diameter not exceeding 150 mm, easily aligning to the specimen but becoming immobile as the force increases; positive location of specimens at the centre of the lower platen shall be provided — visual alignment is not allowed. Specimen (6): manufactured according to EN 13286-50, -51, -52 or -53; the type of compaction and curing is stated in the report. Procedure (7): dimensions measured to an accuracy of 0,5 %; the specimen is weighed to ± 0,25 % and compared with the mass at manufacture, the change in mass recorded (note — if the change is greater than 2 %, the compressive strength result can be reviewed since it could be unrepresentative of the mixture); out-of-parallelism of the faces not exceeding 2 mm in 100 mm — other specimens are discarded or rectified by grinding or capping according to EN 12390-3:2019, Annex A; damaged specimens are not tested; before placing in the machine, excess moisture is wiped off, bearing surfaces cleaned and loose grit removed from the specimen faces; no packing is used between specimen and platens; cubes are compressed perpendicular to or in the direction of casting, and the direction recorded; the specimen is centred to 1 % of the designated size of cube side or diameter; at contact with the upper platen the seating is adjusted for uniform contact. Loading (7.6): the load is applied continuously and uniformly without shock so that rupture occurs within 30–120 s of commencement of loading; on manually controlled machines, as rupture approaches, any tendency of the loading rate to decrease is corrected; on automatically controlled machines the rate is periodically checked to be constant; the maximum force F is recorded; the time between removal of specimens from curing and loading should be minimized to avoid loss of moisture. Assessment of failure (7.7): the mode of failure is assessed using Figures 1–4 — a satisfactory failure is recorded as such, for an unsatisfactory one the pattern number (cubes) or letter (cylinders) is recorded; note — unsatisfactory failures are usually caused by insufficient attention to making, capping and testing specimens, but a machine fault can also be the cause. Result (8): Rc = F/Ac, where Rc — strength in N/mm², F — maximum force in N, Ac — cross-sectional area in mm²; if actual dimensions are within ± 0,5 % of the designated size, the designated size is used, otherwise the actual dimensions; strength is expressed to the nearest 0,1 N/mm² up to 5 N/mm² and 0,5 N/mm² above 5 N/mm². Test report (9.1, items a–l): identification and shape of specimen, method of manufacture, mass at time of test to the nearest 10 g, condition at weighing (as received or saturated), dimensions (actual or designated), method of adjustment of faces, date of test, for cubes — direction of testing relative to casting, bulk density at time of test in kg/m³, compressive strength, type of failure.

STATUS (catalogue cards as of 03.10.2026). The card of PN-EN 13286-41:2022-04 (English version, published 21-04-2022, 13 pages, price group G) has no “Withdrawn” header: Construction Sector, KT 212 Road Construction and Maintenance, ICS 93.080.20, “Introduces: EN 13286-41:2021 [IDT]”, “Replaces: PN-EN 13286-41:2005 — Polish version”. The card of PN-EN 13286-41:2005 (Polish version, 13 pages) has the header “Withdrawn”: withdrawal date 21-04-2022, “Replaced by: PN-EN 13286-41:2022-04”; it introduced EN 13286-41:2003 [IDT]. What changed for the result: according to the foreword of the 2021 edition, the permitted time to failure was widened (now 30–120 s); we do not know the window in the 2003 edition, because we have not read its text.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, data up to 17.09.2026, read 03.10.2026). The number 13286-41 appears in 8 records at 7 laboratories: AB 1110, AB 1211, AB 1484, AB 1605, AB 1641, AB 1669, AB 1783. In the current scopes on the PCA website (read 03.10.2026, issues from 20.10.2025 to 16.09.2026) six give the 2022-04 edition, AB 1211 — “PN-EN 13286-41:2022” (without month). The “Laboratories” tab (“PN-EN 13286-41”) shows all 7 laboratories; checked with the tab query on the production server labcoda.pl on 03.10.2026.

WHAT THE LABORATORIES TEST (items in PCA scopes). “Compressive strength” of hydraulically bound mixtures, bases and improved subgrade of cement-stabilized soil, and cement-stabilized soils (AB 1211). Ranges are given in units of force, not stress: (2–50) kN at AB 1110, (3–50) kN at AB 1211, (10–200) kN at AB 1484, (2–600) kN at AB 1641, (1–2660) kN at AB 1783, (1–3000) kN at AB 1669, (2–3000) kN at AB 1605. AB 1110 cites the standard jointly with its own procedure PBG 15 (“compressive strength of stabilization”); AB 1605 — jointly with PN-S-96012:1997; at AB 1641, AB 1669 and AB 1783 the strength of cement-stabilized soil according to PN-S-96012:1997 is a separate item. Next to it is sampling according to PN-EN 13286-1 and PN-EN 932-1.

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. Loading rate: failure faster than 30 s or slower than 120 s does not comply with 7.6 — the rate of load increase must be matched to the expected strength, which in these mixtures ranges from below 1 MPa to 50 MPa or more (foreword). Packing: no packing between specimen and platens (7.5); uneven faces are rectified only by grinding or capping according to EN 12390-3, Annex A. Centring: visual alignment is forbidden (5.1), and a position deviation greater than 1 % of the size does not comply with 7.5. Moisture: the standard requires minimizing the time between removal from curing and testing to avoid loss of moisture, requires recording the change in mass and, at a change of more than 2 %, allows the result to be reviewed as unrepresentative (7.2, 7.6). Type of failure: a result with an unsatisfactory failure is a number with no guarantee that it describes the material — failure is assessed and recorded (7.7). Units: PCA ranges give force in kN, while the standard gives strength in N/mm²; for a specimen of 100 mm diameter (area about 7854 mm²) a force of 2 kN corresponds to about 0,25 N/mm². Calculation: Ac is calculated from the designated size only if the actual dimensions are within ± 0,5 % (8); this standard does not specify how the specimen is made, it only refers to Parts 50–53 — hence the report must state the method of manufacture and the type of compaction and curing (6, 9.1).

WHAT WE DO NOT GIVE. We do not have Figures 1–4 (failure patterns), the end of 9.1 or 9.2 — so we do not describe the individual failure patterns or the optional report information; according to the table of contents the standard has no precision clause. We do not give strength requirements for mixtures from product standards or from PN-S-96012, because we have not read their text.

Method principle

A specimen of hydraulically bound mixture, manufactured in the laboratory or taken as a core, after checking dimensions, mass and parallelism of the faces, is compressed uniaxially between steel platens (the upper one on a spherical seating), without packing, with a continuous load increase giving failure in 30–120 s; from the maximum force and cross-sectional area the compressive strength Rc = F/Ac in N/mm² is calculated and the type of failure assessed.

Applications

• Hydraulically bound mixtures in road bases and improved subgrade layers — laboratory specimens and cores; 7 laboratories in PCA scopes
• Cement-stabilized soils — in PCA scopes next to tests according to PN-S-96012:1997
• Mixtures with strengths from below 1 MPa to 50 MPa and more — failure time window widened in the 2021 edition

Key parameters

Standard

Standard number

PN-EN 13286-41:2022-04 (wersja angielska; EN 13286-41:2021 IDT)

Title (PL)

Mieszanki niezwiązane i związane spoiwem hydraulicznym — Część 41: Metoda badania wytrzymałości na ściskanie mieszanek związanych hydraulicznie

Title (EN)

Unbound and hydraulically bound mixtures — Part 41: Test method for the determination of the compressive strength of hydraulically bound mixtures

Step-by-step procedure

1. Specimen

   Manufactured according to PN-EN 13286-50…-53 or a core; record the type of compaction and curing. PN-EN 13286-41:2022-04 current (PKN catalogue cards as of 03.10.2026).

2. Dimensions, mass, faces

   Dimensions to 0,5 %, mass ± 0,25 % and its change; parallelism of faces ≤ 2 mm/100 mm — otherwise grinding or capping according to EN 12390-3, Annex A; do not test damaged specimens.

3. Positioning

   Wipe off moisture, clean platens and faces, no packing; cube — record direction relative to casting; centre to 1 %; adjust the seating for uniform contact.

4. Loading

   Continuous, uniform force without shock, failure after 30–120 s; correct the rate on manual control; record Fmax; assess the type of failure using Figures 1–4.

5. Result

   Rc = F/Ac (from the designated size when actual dimensions are within ± 0,5 %), to 0,1 or 0,5 N/mm²; report with bulk density and type of failure.

Required equipment and apparatus

Health and safety (OHS)

• Brittle failure of the specimen under high force can eject fragments — guard the test zone; the part of the standard we read contains no separate safety requirements
• Grinding and capping of faces (EN 12390-3, Annex A) — protection against dust and hot capping compound

Frequently asked questions