FprEN 1991-1-3

SLOVENSKI STANDARD
01-maj-2023
Evrokod 1 - Vplivi na konstrukcije - 1-3. del: Obtežba snega
Eurocode 1 - Actions on structures - Part 1-3: Snow loads
Eurocode 1 - Einwirkungen auf Tragwerke - Teil 1-3: Allgemeine Einwirkungen -
Schneelasten
Eurocode 1 - Actions sur les structures - Partie 1-3 : Charges de neige
Ta slovenski standard je istoveten z: prEN 1991-1-3
ICS:
91.010.30 Tehnični vidiki Technical aspects
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 1991-1-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2023
ICS 91.010.30 Will supersede EN 1991-1-3:2003
English Version
Eurocode 1 - Actions on structures - Part 1-3: General
actions - Snow loads
Eurocode 1 - Actions sur les structures - Partie 1-3: Eurocode 1 - Einwirkungen auf Tragwerke - Teil 1-3:
Actions générales - Charges de neige Allgemeine Einwirkungen, Schneelasten
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 250.
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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1991-1-3:2023 E
worldwide for CEN national Members.

prEN 1991-1-3:2023 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 8
1.1 Scope of EN 1991-1-3 . 8
1.2 Assumptions . 8
2 Normative references . 8
3 Terms, definitions and symbols . 8
3.1 Terms and definitions . 8
3.2 Symbols and abbreviations . 10
3.2.1 Latin upper-case letters . 10
3.2.2 Latin lower case letters . 10
3.2.3 Greek lower-case letters . 11
4 Design situations . 12
4.1 General. 12
4.2 Normal conditions . 12
4.3 Exceptional conditions . 12
5 Modelling of snow load . 12
5.1 Classification of actions . 12
5.2 Design assisted by testing . 12
6 Snow load on the ground . 13
6.1 Characteristic values . 13
6.2 Treatment of exceptional snow loads on the ground . 13
7 Snow load on roofs . 13
7.1 Load arrangements . 13
7.2 Determination of snow load. 14
7.3 Exposure coefficient . 14
7.4 Thermal coefficient . 15
7.5 Snow load shape coefficients . 16
7.5.1 Field of application . 16
7.5.2 Flat roofs . 16
7.5.3 Pitched roofs . 19
7.5.4 Multi-span roofs . 21
7.5.5 Cylindrical roofs . 22
7.5.6 Domes . 24
7.5.7 Roof abutting and close to taller construction works . 25
8 Local Effects . 28
8.1 Local verifications . 28
8.2 Drifting at obstructions . 28
8.3 Drifting at parapets . 29
8.4 Snow overhanging the edge of a roof . 30
8.5 Snow loads on snow guards and other obstacles . 31
8.6 Drifting at intersecting pitched roofs . 31
Annex A (informative) Ground snow load maps . 33
A.1 Use of this Informative Annex . 33
A.2 Scope and field of application . 33
prEN 1991-1-3:2023 (E)
A.3 Treatment of ground snow load measurements . 33
A.4 Zoning . 34
A.5 Climate change effect . 34
Annex B (informative) Adjustment of ground snow load to return period . 35
B.1 Use of this Informative Annex . 35
B.2 Scope and field of application . 35
B.3 Adjustment of the ground snow load according to the return period . 35
Annex C (informative) Bulk snow weight density . 37
C.1 Use of this Informative Annex . 37
C.2 Scope and field of application . 37
C.3 Bulk snow weight density . 37
Bibliography . 38

prEN 1991-1-3:2023 (E)
European foreword
This document (prEN 1991-1-3:2023) has been prepared by Technical Committee CEN/TC 250
“Structural Eurocodes”, the secretariat of which is held by BSI.
CEN/TC 250 is responsible for all Structural Eurocodes and has been assigned responsibility for
structural and geotechnical design matters by CEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 1991-1-3:2003.
The first generation of EN Eurocodes was published between 2002 and 2007. This document forms part
of the second generation of the Eurocodes, which have been prepared under Mandate M/515 issued to
CEN by the European Commission and the European Free Trade Association.
The Eurocodes have been drafted to be used in conjunction with relevant execution, material, product
and test standards, and to identify requirements for execution, materials, products and testing that are
relied upon by the Eurocodes.
The Eurocodes recognize the responsibility of each Member State and have safeguarded their right to
determine values related to regulatory safety matters at national level through the use of National
Annexes.
prEN 1991-1-3:2023 (E)
Introduction
0.1 Introduction to the Eurocodes
The structural Eurocodes comprise the following standards generally consisting of a number of Parts:
— EN 1990, Eurocode: Basis of structural and geotechnical design
— EN 1991, Eurocode 1: Actions on structures
— EN 1992, Eurocode 2: Design of concrete structures
— EN 1993, Eurocode 3: Design of steel structures
— EN 1994, Eurocode 4: Design of composite steel and concrete structure
— EN 1995, Eurocode 5: Design of timber structures
— EN 1996, Eurocode 6: Design of masonry structures
— EN 1997, Eurocode 7: Geotechnical design
— EN 1998, Eurocode 8: Design of structures for earthquake resistance
— EN 1999, Eurocode 9: Design of aluminium structures
— New parts are under development, e.g. Eurocode for design of structural glass
The Eurocodes are intended for use by designers, clients, manufacturers, constructors, relevant
authorities (in exercising their duties in accordance with national or international regulations),
educators, software developers, and committees drafting standards for related product, testing and
execution standards.
NOTE Some aspects of design are most appropriately specified by relevant authorities or, where not specified,
can be agreed on a project-specific basis between relevant parties such as designers and clients. The Eurocodes
identify such aspects making explicit reference to relevant authorities and relevant parties.
0.2 Introduction to EN 1991
(1) EN 1991 provides the actions to be considered for the structural design of buildings, bridges and
other civil engineering works, or parts thereof, including temporary structures, in conjunction with
EN 1990 and the other Eurocodes.
(2) The actions on structures, including in some cases geotechnical structures in conjunction with
EN 1997 as appropriate, provided in EN 1991 are intended to be applied in conjunction with the other
Eurocodes for the verification of safety, serviceability and durability, as well as ro
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