SIST EN 1996-1-2:2005

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Eurocode 6 - Design of masonry structures - Part 1-2: General rules - Structural fire designEvrokod 6: Projektiranje zidanih konstrukcij – 1-2 del: Splošna pravila – Požarnoodporno projektiranjeEurocode 6 - Calcul des ouvrages en maçonnerie - Partie 1-2: Regles générales - Calcul du comportement au feuEurocode 6 - Bemessung und Konstruktion von Mauerwerksbauten - Allgemeine Regeln -Teil 1-2: Tragwerksbemessung für den BrandfallTa slovenski standard je istoveten z:EN 1996-1-2:2005SIST EN 1996-1-2:2005en91.080.30Zidane konstrukcijeMasonry91.010.30Technical aspects13.220.50Požarna odpornost gradbenih materialov in elementovFire-resistance of building materials and elementsICS:SIST ENV 1996-1-3:2004SIST ENV 1996-1-2:20041DGRPHãþDSLOVENSKI
STANDARDSIST EN 1996-1-2:200501-oktober-2005

EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 1996-1-2
May 2005 ICS 13.220.50; 91.010.30; 91.080.30 Supersedes ENV 1996-1-2:1995 English version
Eurocode 6 - Design of masonry structures - Part 1-2: General rules - Structural fire design
Eurocode 6 - Calcul des ouvrages en maçonnerie - Partie 1-2: Règles générales - Calcul du comportement au feu
Eurocode 6 - Bemessung und Konstruktion von Mauerwerksbauten - Teil 1-2: Allgemeine Regeln - Tragwerksbemessung für den Brandfall This European Standard was approved by CEN on 4 November 2004.
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. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists 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 Central Secretariat has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
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B-1050 Brussels © 2005 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1996-1-2:2005: E

EN1996-1-2:2005
2 Contents Page Foreword.4 Background of the Eurocode programme.4 Status and field of application of Eurocodes.5 National Standards implementing Eurocodes.6 Links between Eurocodes and products harmonised technical specifications (ENs and ETAs).6 Additional information specific to EN 1996-1-2.7 National Annex for EN 1996-1-2.9 Section 1. General.9 1.1 Scope.9 1.2 Normative references.10 1.3 Assumptions.11 1.4 Distinction between Principles and application Rules.11 1.5 Definitions.11 1.5.1 Special terms relating to fire design in general.12 1.5.2 Special terms relating to calculation methods.13 1.6 Symbols.13 Section 2. Basic principles and rules.15 2.1 Performance requirement.15 2.1.1 General.15 2.1.2 Nominal fire exposure.15 2.1.3 Parametric fire exposure.16 2.2 Actions.16 2.3 Design values of material properties.16 2.4 Assessment methods.17 2.4.1 General.17 2.4.2
Member analysis.18 2.4.3 Analysis of part of the structure.20

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3 2.4.4 Global structural analysis.20 Section 3.
Materials.20 3.1 Units.20 3.2 Mortar.20 3.3 Mechanical properties of masonry.20 3.3.1 Mechanical properties of masonry at normal temperature.20 3.3.2 Strength and deformation properties of masonry at elevated temperature.21 3.3.2.1 General.21 3.3.2.2 Unit mass.21 3.3.3 Thermal properties.21 3.3.3.1 Thermal elongation.21 3.3.3.2 Specific heat capacity.21 3.3.3.3 Thermal conductivity.21 Section 4. Design Procedures for obtaining Þre resistance of masonry walls.21 4.1 General information on the design of walls.21 4.1.1 Wall types by function.21 4.1.2 Cavity walls and untied walls comprising independent leaves.22 4.2 Surface finishes – rendering mortar and plaster.24 4.3 Additional requirements for masonry walls.24 4.4 Assessment by testing.24 4.5 Assessment by tabulated data.25 4.6 Assessment by calculation.25 Section 5. Detailing.25 5.1 General.25 5.2 Junctions and joints.26 5.3 Fixtures, pipes and cables.26 Annex A (Informative) Guidance on selection of fire resistance periods.28 Annex B (Normative) Tabulated fire resistance of masonry walls.29 Annex C (Informative)
Simplified calculation model.63 Annex D (Informative)
Advanced calculation method.71 Annex E (Informative)
Examples of connections that meet the requirements of Section 5.78

EN1996-1-2:2005
4 Foreword
This document (EN 1996-1-2:2005) has been prepared by Technical Committee CEN/TC 250 "Structural Eurocodes", the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2005 and conflicting national standards shall be withdrawn at the latest by March 2010. This document supersedes ENV 1996-1-2:1995. CEN/TC 250 is responsible for all Structural Eurocodes. Background of the Eurocode programme In 1975, the Commission of the European Community decided on an action programme in the field of construction, based on article 95 of the Treaty. The objective of the programme was the elimination of technical obstacles to trade and the harmonisation of technical specifications. Within this action programme, the Commission took the initiative to establish a set of harmonised technical rules for the design of construction works which, in a first stage, would serve as an alternative to the national rules in force in the Member States and, ultimately, would replace them.
For fifteen years, the Commission, with the help of a Steering Committee with Representatives of Member States, conducted the development of the Eurocodes programme, which led to the first generation of European codes in the 1980’s.
In 1989, the Commission and the Member States of the EU and EFTA decided, on the basis of an agreement1 between the Commission and CEN, to transfer the preparation and the publication of the Eurocodes to the CEN through a series of Mandates, in order to provide them with a future status of European Standard (EN). This links de facto the Eurocodes with the provisions of all the Council’s Directives and/or Commission’s Decisions dealing with European standards (e.g. the Council Directive 89/106/EEC on construction products - CPD - and Council Directives 93/37/EEC, 92/50/EEC and 89/440/EEC on public works and services and equivalent EFTA Directives initiated in pursuit of setting up the internal market). The Structural Eurocode programme comprises the following standards generally consisting of a number of Parts: EN 1990 Eurocode : Basis of Structural 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 structures
1 Agreement between the Commission of the European Communities and the European Committee for Standardisation (CEN) concerning the work on EUROCODES for the design of building and civil engineering works (BC/CEN/03/89).

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5 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
Eurocode standards recognise the responsibility of regulatory authorities in each Member State and have safeguarded their right to determine values related to regulatory safety matters at national level where these continue to vary from State to State. Status and field of application of Eurocodes The Member States of the EU and EFTA recognise that EUROCODES serve as reference documents for the following purposes: - as a means to prove compliance of building and civil engineering works with the essential requirements of Council Directive 89/106/EEC, particularly Essential Requirement N°1 – Mechanical resistance and stability – and Essential Requirement N°2 – Safety in case of fire; - as a basis for specifying contracts for construction works and related engineering services; - as a framework for drawing up harmonised technical specifications for construction products (ENs and ETAs) The Eurocodes, as far as they concern the construction works themselves, have a direct relationship with the Interpretative Documents2 referred to in Article 12 of the CPD, although they are of a different nature from harmonised product standards3. Therefore, technical aspects arising from the Eurocodes work need to be adequately considered by CEN Technical Committees and/or EOTA Working Groups working on product standards with a view to achieving full compatibility of these technical specifications with the Eurocodes. The Eurocode standards provide common structural design rules for everyday use for the design of whole structures and component products of both a traditional and an innovative nature. Unusual forms of construction or design conditions are not specifically covered and additional expert consideration will be required by the designer in such cases.
2 According to Art. 3.3 of the CPD, the essential requirements (ERs) shall be given concrete form in interpretative documents for the creation of the necessary links between the essential requirements and the mandates for harmonised ENs and ETAGs/ETAs. 3 According to Art. 12 of the CPD the interpretative documents shall : a) give concrete form to the essential requirements by harmonising the terminology and the technical bases and indicating classes or levels for each requirement where necessary ; b) indicate methods of correlating these classes or levels of requirement with the technical specifications, e.g. methods of calculation and of proof, technical rules for project design, etc. ; c) serve as a reference for the establishment of harmonised standards and guidelines for European technical approvals. The Eurocodes, de facto, play a similar role in the field of the ER 1 and a part of ER 2.

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6 National Standards implementing Eurocodes The National Standards implementing Eurocodes will comprise the full text of the Eurocode (including any annexes), as published by CEN, which may be preceded by a National title page and National foreword, and may be followed by a National Annex. The National Annex
may only contain information on those parameters which are left open in the Eurocode for national choice, known as Nationally Determined Parameters, to be used for the design of buildings and civil engineering works to be constructed in the country concerned, i.e. : - values and/or classes where alternatives are given in the Eurocode, - values to be used where a symbol only is given in the Eurocode, - country specific data (geographical, climatic, etc.), e.g. snow map, - the procedure to be used where alternative procedures are given in the Eurocode, and it may also contain - decisions on the application of informative annexes, - references to non-contradictory complementary information to assist the user to apply the Eurocode. Links between Eurocodes and products harmonised technical specifications (ENs and ETAs) There is a need for consistency between the harmonised technical specifications for construction products and the technical rules for works4. Furthermore, all the information accompanying the CE Marking of the construction products which refer to Eurocodes should clearly mention which Nationally Determined Parameters have been taken into account. This European Standard is part of EN 1996 which comprises the following parts: EN 1996-1-1: Common rules for reinforced and unreinforced masonry structures. EN 1996-1-2: General Rules - Structural Fire Design. EN 1996-2: Design, Selection of materials and execution of masonry EN 1996-3: Simplified calculation methods and simple rules for masonry structures EN 1996-1-2 is intended to be used together with EN 1990, EN 1991-1-2, EN 1996-1-1, EN 1996-2 and EN 1996-3
4 see Art.3.3 and Art.12 of the CPD, as well as clauses 4.2, 4.3.1, 4.3.2 and 5.2 of ID 1.

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7 Additional information specific to EN 1996-1-2 The general objectives of fire protection are to limit risks with respect to the individual and society, neighbouring property, and where required, directly exposed property, in the case of fire. The Construction Products Directive 89/106/EEC gives the following essential requirement for the limitation of fire risks: "The construction works must be designed and built in such a way that, in the event of an outbreak of fire - the load bearing resistance of the construction can be assumed for a specified period of time - the generation and spread of fire and smoke within the works are limited - the spread of fire to neighbouring construction works is limited
- the occupants can leave the works or can be rescued by other means - the safety of rescue teams is taken into consideration". According to the Interpretative Document No 2 "Safety in Case of Fire" the essential requirement may be observed by following various possibilities for fire safety strategies prevailing in the Member States like conventional fire scenarios (nominal fires) or 'natural' (parametric) fire scenarios, including passive and/or active fire protection measures. The fire parts of Structural Eurocodes deal with specific aspects of passive fire protection in terms of designing structures and parts thereof for adequate load bearing resistance that could be needed for safe evacuation of occupants and fire rescue operations and for limiting fire spread as relevant. Required functions and levels of performance are generally specified by the national authorities - mostly in terms of a standard fire resistance rating. Where fire safety engineering for assessing passive and active measures is acceptable, requirements by authorities will be less prescriptive and may allow for alternative strategies. This Part 1-2, together with EN 1991-1-2, Actions on structures exposed to fire, supplements EN 1996-1-1, so that the design of masonry structures can comply with normal and fire requirements. Supplementary requirements concerning, for example - the possible installation and maintenance of sprinkler systems - conditions on occupancy of building or fire compartment - the use of approved insulation and coating materials, including their maintenance
are not given in this document, as they are subject to specification by the competent authority.

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8 A full analytical procedure for structural fire design would take into account the behaviour of the structural system at elevated temperatures, the potential heat exposure and the beneficial effects of active fire protection systems, together with the uncertainties associated with these three features and the importance of the structure (consequences of failure). At the present time it is possible to perform a calculation procedure for determining adequate performance which incorporates some, if not all, of these parameters and to demonstrate that the structure, or its components, will give adequate performance in a real building fire. However the principal current procedure in European countries is one based on results from standard fire resistance tests. The grading system in regulations, which call for specific periods of fire resistance, takes into account (though not explicitly), the features and uncertainties described above. Due to the limitations of the test method, further tests or analyses may be used. Nevertheless, the results of standard fire tests form the bulk of input for calculation procedures for structural fire design. This standard therefore deals principally with the design for the standard fire resistance. Application of this Part 1-2 of Eurocode 6 with the thermal actions given in EN 1991-1-2, is illustrated in figure 0.1. For design according to this part, EN 1991-1-2 is required for the determination of temperature fields in structural elements, or when using general calculation models for the analysis of the structural response. Tabulardata Advanced calculationmodelsCalculation ofactions atboundaries
Memberanalysis Advanced calculationmodels Calculation ofaction effectsat boundaries Advanced calculationmodels Selection of actions Prescriptive Rules(Thermal actions given by Nominal fire)
Calculation ofactionsat boundariesMemberanalysisAdvanced calculationmodelsAdvanced calculationmodels Calculation ofaction effectsat boundaries Advanced calculationmodels
Selection of actionsSelection ofsimple or advanced fire models Performance-Based Code(Physically based thermal actions)
Project Design Analysis of partof the structureAnalysis ofentire structureSimple calculationmodelsAnalysis of partof the structureAnalysis of entirestructureSimple calculationmodelsSimple calculationmodels Figure 0.1 : Design procedures

EN1996-1-2: 2005
9 Where simple calculation models are not available, the Eurocode fire parts give design solutions in terms of tabular data (based on tests or general calculation models), which may be used within the specified limits of validity. National Annex for EN 1996-1-2 This standard gives alternative procedures, values and recommendations for classes, with notes indicating where national choices may have to be made. Therefore the National Standard implementing EN 1996-1-2 should include a National annex which contains all Nationally Determined Parameters to be used for the design of buildings and civil engineering works constructed in the relevant country.
National choice is allowed in EN 1996-1-2 through clauses: - 2.2 (2) Actions; - 2.3 (2) Design values of material properties; - 2.4.2 (3) Member analysis; - 3.3.3.1(1) Thermal elongation; - 3.3.3.2 (1) Specific heat; - 3.3.3.3 Thermal conductivity; - 4.5(3) Value of Glo; - Annex B Tabulated values of fire resistance of masonry walls; - Annex C Values of constant c.
Section 1. General 1.1 Scope (1)P This Part 1-2 of EN 1996 deals with the design of masonry structures for the accidental situation of fire exposure, and is intended to be used in conjunction with EN 1996-1-1, EN 1996-2, 1996-3 and EN 1991-1-2. This part 1-2 only identifies differences from, or supplements to, normal temperature design. (2)P This Part 1-2 deals only with passive methods of fire protection. Active methods are not covered. (3)P This Part 1-2 applies to masonry structures which, for reasons of general fire safety, are required to fulfil certain functions when exposed to fire, in terms of: - avoiding premature collapse of the structure (load bearing function) - limiting fire spread (flames, hot gases, excessive heat) beyond designated areas (separating function)

EN1996-1-2:2005
10 (4)P This Part 1-2 gives principles and application rules for designing structures for specified requirements in respect of the aforementioned functions and levels of performance. (5)P This Part 1-2 applies to structures, or parts of structures, that are within the scope of EN 1996-1-1, EN 1996-2 and EN 1996-3 and are designed accordingly.
(6)P This Part 1-2 does not cover masonry built with Natural Stone units to EN771-6 (7)P This Part 1-2 deals with the following: - non-loadbearing internal walls. - non-loadbearing external walls. - loadbearing internal walls with separating or non-separating functions. - loadbearing external walls with separating or non-separating functions. 1.2 Normative references This European standard incorporates by dated or undated references, provisions from other publications. These Normative references are cited at appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to, or revisions of, any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references, the latest edition of the publication referred to applies (including amendments). EN 771-1 Specification for masonry units - Part 1: Clay masonry units. EN 771-2 Specification for masonry units - Part 2: Calcium silicate masonry units EN 771-3 Specification for masonry units - Part 3: Aggregate concrete masonry units (dense and light-weight aggregates) EN 771-4 Specification for masonry units - Part 4: Autoclaved aerated concrete masonry units EN 771-5 Specification for masonry units - Part 5: Manufactured stone masonry units EN 771-6 Specification for masonry units
- Part 6 : Natural stone units EN 772-13 Methods of test for masonry units - Part 13: Determination of net and gross dry density of masonry units (except for natural stone) EN 998-1 Specification for mortar for masonry - Part 1: Rendering and plastering mortar EN 998-2 Specification for mortar for masonry - Part 2: Masonry mortar. EN 1363
Fire resistance
Part 1: General requirements
Part 2: Alternative and additional requirements

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11 EN 1364
Fire resistance tests of non-loadbearing elements.
Part 1 Walls EN 1365
Fire resistance tests of loadbearing elements.
Part 1 Walls EN 1365
Fire resistance tests of loadbearing elements.
Part 4 Columns EN 1366 Fire resistance tests for service installations.
Part 3 Penetration seals EN 1990 Basis of design for Structural Eurocodes EN 1991 Basis of design and actions on structures:
Part 1-1: General actions - Densities, self-weight, imposed loads for buildings
Part 1-2: Actions on structures exposed to fire; EN 1996 Design of masonry structures:
Part 1.1: Common rules for reinforced and unreinforced masonry structures
Part 2: Design, selection of materials and execution of masonry
Part 3: Simplified and simple rules for masonry structures prEN 12602 Prefabricated reinforced components.of autoclaved aerated concrete
Annex C – Resistance to fire design of AAC components and structures EN 13279-1 Gypsum and gypsum-based building plaster - Part 1: Definitions and requirements
1.3 Assumptions (1) P In addition to the general assumptions of EN 1990 the following assumptions apply: - Any passive fire protection systems taken into account in the design will be adequately maintained. - The choice of the relevant design fire scenario is made by appropiately qualified and experienced personnel. 1.4 Distinction between Principles and application Rules (1) The rules given in EN 1990 clause 1.4 apply. 1.5 Definitions For the purposes of this Part 1-2 of EN 1996, the definitions of EN 1990 and of EN 1991-1-2 apply with the following additional definitions:

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12 1.5.1 Special terms relating to fire design in general 1.5.1.1 Fire protection material Any material or combination of materials applied to a structural member for the purpose of increasing its fire resistance
1.5.1.2 Fire wall A wall separating two spaces (generally two fire compartments or buildings) which is designed for fire resistance and structural stability, including resistance to mechanical impact (Criterion M) such that, in the case of fire and failure of the structure on one side of the wall, fire spread beyond the wall is avoided (so that a Fire wall is designated REI-M or EI-M) NOTE: In some countries a fire wall has been defined as a separating wall between fire compartments without a requirement for resistance to mechanical impact; the definition above should not be confused with this more limited one. Fire walls may have to fulfil additional requirements not given in this part 1-2, these being given in the regulations of each country 1.5.1.3 Loadbearing wall A flat, membrane-like component predominantly subjected to compressive stress, for supporting vertical loads, for example floor loads, and also for supporting horizontal loads, for example wind loads. 15.1.4 Non-loadbearing wall A flat membrane-like building component loaded predominantly only by its dead weight, and which does not provide bracing for loadbearing walls. It may however, be required to transfer horizontal loads acting on its surface to loadbearing building components such as walls or floors. 1.5.1.5 Separating wall A wall exposed to fire on one side only. 1.5.1.6 Non-separating wall A loadbearing wall exposed to fire on two or more sides. 1.5.1.7 Normal temperature design The ultimate limit state design for ambient temperatures in accordance with Part 1-1 of EN 1992 to 1996 or ENV 1999
1.5.1.8 Part of structure The isolated part of an entire structure with appropriate support and boundary conditions.

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13 1.5.2 Special terms relating to calculation methods 1.5.2.1 Ineffective cross section The area of a cross section that is assumed to become ineffective for fire resistance purposes. 1.5.2.2. Effective cross section The cross section of a member used in structural fire design, obtained by removing parts of the cross section with assumed zero strength and stiffness. 1.5.2.3. Residual cross section That part of the cross section of the original member which is assumed to remain after deduction of the thickness which is ineffective for fire-resistance purposes. 1.5.2.4 Structural failure of a wall in the fire situation When the wall loses its ability to carry a specified load after a certain period of time 1.5.2.5 Maximum stress level For a given temperature, the stress level at which the stress-strain relationship of masonry is truncated to a yield plateau. 1.6 Symbols For the purpose of this Part 1-2, the following symbols apply, in addition to those given in EN 1991-1-1 and EN 1991-1-2: E 30 or E 60,. . ., member meeting the integrity criterion, E, for 30, or 60 . minutes in standard fire exposure. I 30 or I 60,. . ., member meeting the thermal insulation criterion, I, for 30, or 60 . minutes in standard fire exposure. M 90 or M 120,. . ., member meeting the mechanical resistance criterion, M, for 90, or 120 . minutes after standard fire exposure when mechanical impact applied . R 30 or R 60,. . .,
member meeting the load bearing criterion, R, for 30, or 60 . minutes in standard fire exposure, A total area of masonry Am surface area of a member per unit length; Ap area of the inner surface of the fire protection material per unit length of the member; A1 area of masonry up to temperature 1; A2 area of masonry between temperatures 1 and 2;

EN1996-1-2:2005
14 c constant obtained from stress strain tests at elevated temperature (with subscripts) ca specific heat capacity of masonry; ct combined thickness of webs and shells (given as a percentage of the width of a unit) e eccentricity due to variation of temperature across masonry; fb characteristic unit strength fd1 design compressive strength of masonry at less than or equal to 1; fd2 design strength of masonry in compression between 1 and 2°C hef effective height of the wall l length at 20°C ; lF length of a wall for a period of fire resistance NEd design value of the vertical load; NRd,fi2 design value of the resistance in fire; NRk characteristic value of vertical resistance of masonry wall or column; nvg no value given tF thickness of a wall for a period of fire resistance tfi,d time of fire classification (eg 30 minutes) for a standard fire in accordance with EN 1363; tFr thickness of the cross-section whose temperature does not exceed θ2 . proportion of load on a wall; αt coefficient of thermal expansion of masonry εT thermal strain Glo a safety factor for use in fire tests; ∆t time interval; ηfi reduction factor for design load level in the fire situation; θ1 temperature up to which the cold strength of masonry may be used; θ2 temperature above which any residual masonry strength is ignored; a thermal conductivity;

EN1996-1-2: 2005
15 µ0 degree of utilisation at time
t = 0.
gross dry density of the masonry units, measured in accordance with EN 772- 13.
Section 2. Basic principles and rules 2.1 Performance requirement 2.1.1 General
(1)P Where mechanical resistance is required, structures shall be designed and constructed in such a way that they maintain their loadbearing function during the relevant fire exposure. (2)P Where compartmentation is required, the elements forming the boundaries of the fire compartment, including joints, shall be designed and constructed in such a way that they maintain their separating function during the relevant fire exposure, i.e. -
no integrity failure shall occur, in order to prevent the passage of flames and hot gases through the member, and to prevent the occurrence of flames on the unexposed side -
no insulation failure shall occur in order to limit the temperature rise of the unexposed face within specified levels. -
when required, resistance to mechanical impact (M) -
when required, limitation of the thermal radiation from the unexposed side. (3)P Deformation criteria shall be applied where the means of protection, or the design criteria for separating elements, requires consideration of the deformation of the load bearing structure. (4) Consideration of the deformation of the load bearing structure is not necessary in the following case: - the separating elements have to fulfil requirements according to a nominal fire exposure. 2.1.2 Nominal fire exposure (1)P For the standard fire exposure, members shall comply with criteria, R (mechanical resistance). E (integrity), I (insulation) and M (mechanical impact) as follows: - Loadbearing only
criterion R - Separating only
criteria EI - Separating and loadbearing
criteria REI - Loadbearing, separating and mechanical impact
criteria REI-M - Separating and mechanical impact
criteria EI-M
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16 (2) Criterion R is assumed to be satisfied when the load bearing function is maintained throughout the required time of fire exposure.
(3) Criterion I is assumed to be satisfied when the mean temperature of the unexposed face does not rise by more 140 ºK, and the maximum temperature rise at any point of that surface does not exceed 180 ºK (4) Criterion E is assumed to be satisfied when the passage of flames and hot gases through the member is prevented. (5) Where a vertical separating element, with or without a load-bearing function, is required to comply with an impact resistance requirement, (criterion M), the element should resist the application of the horizontal concentrated load specified in EN 1363 Part 2. (6) With the external fire exposure curve the same criteria as (1)P should apply, however the reference to this specific curve should be identified by the letters “ef”. 2.1.3 Parametric fire exposure (1) The load-bearing function is satisfied when collapse is prevented for the complete duration of the fire, including the decay phase, or for a prescribed period of time. (2) The separating function, with respect to insulation, is satisfied when the following criteria are met: - the mean temperature rise over the whole of the non-exposed surface does not exceed 140ºK and the maximum temperature rise of that surface at any point does not exceed 180ºK, at the time of the maximum gas temperature, - the mean temperature rise over the whole of the non-exposed surface does not exceed 180ºK, and the maximum temperature rise at any point of that surface does not exceed 220ºK during the decay phase of the fire or up to a required period of time.
2.2 Actions (1)P The thermal and mechanical actions shall be obtained from EN 1991-1-2. (2) The emissivity of a masonry surface should be taken as 0m.
NOTE: The value to be ascribed to 0m in a Country may be found in its National Annex. The value will depend on the material of the masonry. 2.3 Design values of material properties (1)P Design values of the mechanical (material strength and deformation) properties, Xd,fi, are defined as follows:
Xd,fi = k Xk / M,fi (2.1) where: Xk
is the characteristic value of the strength or deformation property of the material (eg fk) for normal temperature design to EN 1996-1-1;

EN1996-1-2: 2005
17 k is the reduction factor for the strength or deformation property
(Xk, / Xk) , dependent on the material temperature; M,fi is the partial safety factor for the relevant material property, for the fire situation. (2)P Design values of the thermal properties, Xd,fi, of materials are defined as follows: (i) if an increase of the property is favourable for safety:
Xd,fi = Xk, / M,fi (2.2a) or (ii) if an increase of the property is unfavourable for safety:
Xd,fi = M,fi X k, (2.2b) where: X k, is the value of the material property in fire design, generally dependent on the material temperature, (see section 3); NOTE: The value of γM,fi to be ascribed in a Country may be found in its National Annex. For thermal properties of masonry the recommended value of the partial safety factor M,fi for the fire situation is 1,0. For mechanical properties of masonry, the recommended value of the partial safety factor M,fi for the fire situation is 1,0. 2.4 Assessment methods 2.4.1 General (1)P The model of the structural system adopted for design in the fire situation shall reflect the expected performance of the structure in fire. (2)P The analysis for the fire situation may be carried out using one of the following: - testing the structure - tabulated data - member analysis - analysis of part of the structure - global structural analysis (3)P It shall be verified for the relevant duration of fire exposure that
Efi,d ≤ Rfi,t,d (2.3) Where Efi,d is the design effect of actions for the fire situation, determined in accordance with EN 1991-1-2, including the effects of thermal expansion and deformation
Rfi,t, d is the corresponding design resistance in the fire situation.

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18 (4) The structural analysis for the normal situation should be carried out in accordance with EN 1990 5.1.4(2). (5)
In order to verify standard fire resistance requirements, a member analysis is sufficient. (6) Where application rules given in this Part 1-2 are only valid for the standard temperature-time curve, this is identified in the relevant clauses (7)P Tabulated data given in this part is based on the standard temperature-time curve in accordance with EN 1363.
(8)P
As an alternative to design by calculation, fire resistance may be based on the results of fire tests, or on fire tests in combination with calculation (see EN1990 5.2). 2.4.2
Member analysis
(1) The effect of actions should be determined for time t=0 using combination factors 1,1 or 2,1 according to EN 1991-1-2. (2) As a simplification to (1), the effect of 2,1 on actions Ed,fi may be obtained from a structural analysis for normal temperature design as:
Ed,fi
= fi Ed (2.4) where: Ed is the design value of the corresponding force or moment for normal temperature design, for a fundamental combination of actions (see EN 1990); fi is the reduction factor for the design load level for the fire situation. (3) The reduction factor ¾fi for load combination (6.10) in EN 1990 should be taken as:
fi =Q + GQ + Gk,1Q,1kGk,1fikγγψ (2.5) or for load combinations (6.10a) and (6.10b) in EN 1990 as the smaller value given by the two following expressions:
fi = Q + GQ + Gfik,11,0Q,1kGk,1kψγγψ (2.5a)
fi = Q + GQ + Gk,1Q,1kGk,1fikγγξψ (2.5b) where: Qk,1 is the principal variable load; Gk is the characteristic value of a permanent action;

EN1996-1-2: 2005
19 G is the partial factor for permanent actions; Q,1 is the partial factor for variable action 1; fi is the combination factor for frequent values, given either by 1,1 or 2,1
ξ is a reduction factor for unfavourable permanent actions G. NOTE 1: An example of the variation of the reduction factor ηfi versus the load ratio Qk,1/Gk for different values of the combination factor fi = 1,1 according to expression (2.5) is shown in the figure to this note with the following assumptions: γGA = 1,0, γG = 1,35 and γQ = 1,5. Use of expressions (2.5a) and (2.5b) will give figures slightly higher than those in the figure.
The values of partial factors for use in a Country may be found in its National Annex. Recommended values are given in EN 1990. The choice of expression (6.10) or (6.10)a and (6.10)b may also be found in the National Annex.
3,00,0 0,5 1,01,52,02,50,2 0,3 0,4 0,5 0,6 0,7 0,8 Q
/ Gk,1
kη fi 1,1ψ =
0,7 1,1ψ =
0,9 1,1ψ =
0,5 1,1ψ =
0,2
Variation of the reduction factor fi with the load ratio Qk,1 / Gk NOTE 2: As a simplification the recommended value of fi = 0,65 may be used, except for imposed load
category E as given in EN 1990 (areas for storage and industrial activity) for which the recommended value is 0,7. (4) Only the effects of thermal deformations resulting from thermal gradients across the cross-section need to be considered. The effects of axial or in-plane thermal expansions may be neglected. (5) The boundary conditions at supports and ends of a member may be assumed to remain unchanged throughout the fire exposure. (6) Tabulated data, simplified or advanced calculation methods are suitable for verifying members under fire conditions. NOTE: Annexes B, C and D give information on tabulated data, simplified and advanced calculation methods.

EN1996-1-2:2005
20 2.4.3 Analysis of part of the structure (1) The effect of actions should be determined for time t=0 using combination factors 1,1 or 2,1 according to EN 1991-1-2. (2) As an alternative to carrying out a structural analysis for the fire situation at time
t = 0, the reactions at supports and internal forces and moments at boundaries of part of the structure may be obtained from a structural analysis for normal temperature as given in 2.4.1(4) (3) The part of the structure to be analysed should be specified on the basis of the potential thermal expansions and deformations, such that their interaction with other parts of the structure can be approximated by time-independent support and boundary conditions during fire exposure. (4)P Within the part of the structure to be analysed, the relevant failure mode in fire exposure, the temperature-dependent material properties and member stiffnesses, effects of thermal expansions and deformations (indirect fire actions) shall be taken into account (5) The boundary conditions at supports and forces and moments at boundaries of part of the structure may be assumed to remain unchanged throughout the fire exposure. 2.4.4 Global structural analysis
(1)P When global structural analysis for the fire situation is carried out, the relevant failure mode in fire exposure, the temperature-dependent material properties and member stiffness, effects of thermal expansions and deformations (indirect fire actions) shall be taken into account. Section 3.
Materials 3.1 Units (1) The requirements for masonry units given in EN 1996-1-1 apply to this Part with the following addition: - Group 1S: Units containing less than 5% of formed voids by volume; additionally,they may contain indentations, for example frogs, grip holes or grooves in the bed face, if such indentations will be filled with mortar in the finished wall. 3.2 Mortar (1) The requirements for mortar given in
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