prEN 679

SLOVENSKI STANDARD
01-julij-2026
Ugotavljanje tlačne trdnosti avtoklaviranega celičastega betona
Determination of the compressive strength of autoclaved aerated concrete
Bestimmung der Druckfestigkeit von dampfgehärtetem Porenbeton
Détermination de la résistance à la compression du béton cellulaire autoclavé
Ta slovenski standard je istoveten z: prEN 679
ICS:
91.100.30 Beton in betonski izdelki Concrete and concrete
products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2026
ICS 91.100.30 Will supersede EN 679:2005
English Version
Determination of the compressive strength of autoclaved
aerated concrete
Détermination de la résistance à la compression du Bestimmung der Druckfestigkeit von dampfgehärtetem
béton cellulaire autoclavé Porenbeton
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 177.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 679:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Principle . 4
5 Test apparatus . 4
6 Test specimens . 4
6.1 Sample . 4
6.2 Shape and size of test specimens . 5
6.3 Number of specimens . 5
6.4 Preparation of test specimens . 5
6.5 Measurement of test specimens and determination of their volume . 5
6.6 Conditioning of the test specimens . 6
6.6.1 General. 6
6.6.2 Procedure a) Conditioning to (6 ± 2) % by mass moisture content . 6
6.6.3 Procedure b) Conditioning to the oven dry condition (70 ± 5) °C . 6
7 Testing procedure . 7
7.1 Compression test . 7
7.2 Determination of actual moisture content and dry density of test specimens . 7
8 Test results . 7
9 Test report . 8

European foreword
This document (prEN 679:2026) has been prepared by Technical Committee CEN/TC 177 “Prefabricated
reinforced components of autoclaved aerated concrete or light-weight aggregate concrete with open
structure”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 679:2005.
This document includes the following significant technical changes with respect to EN 679:2005:
— incorporation of procedure for additional conditioning [drying to constant mass at temperature of
(70 ± 5) °C of specimens before testing as stated in the test standard for masonry units
(EN 772-1:2016, 7.3.3 b))];
— in order to meet the performance requirements as laid down in the product standard for
prefabricated components of autoclaved aerated concrete, a number of standardized test methods
are necessary.
1 Scope
This document specifies the procedure for the determination of the compressive strength of autoclaved
aerated concrete.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 678, Determination of the dry density of autoclaved aerated concrete
EN 1353, Determination of moisture content of autoclaved aerated concrete
EN 12390-4, Testing hardened concrete — Part 4: Compressive strength — Specification for testing
machines
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
4 Principle
The compressive strength is determined on test specimens as the ratio between the rupture load in axial
compression and the cross-sectional area of the test specimen perpendicular to the loading direction.
5 Test apparatus
a) Saw for cutting test specimens;
b) compression testing machine, which meets the requirements of EN 12390-4, machine class 1 or 2;
c) calipers, capable of reading the dimensions of the test specimens to an accuracy of 0,1 mm;
d) ventilated drying ovens, capable of maintaining required temperatures for conditioning and drying
test specimens: (≤60 °C), (70 ± 5) °C and (105 ± 5) °C;
e) straight edge, at least 200 mm long, a 0,1 mm-feeler gauge, a 1 mm-feeler gauge, and a square;
f) balance, capable of determining the mass of the test specimens to an accuracy of 0,1 %.
6 Test specimens
6.1 Sa
...