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Принципи розрахунку за граничним станом
(1)Р Граничні стани можуть стосуватись тільки кам’яних споруд або таких інших матеріалів, що використовуються для частин конструкції, для якої мають бути зроблені посилання на відповідні Частини
EN 1992, EN 1993, EN 1994, EN 1995 та EN 1999.
(2)Р Для кам’яних споруд критичний граничний стан та граничне значення експлуатаційної придатності мають розглядатися для всіх аспектів конструкції, включаючи допоміжні компоненти кам’яної кладки.
(3)Р Для кам’яних конструкцій усі відповідні проектні рішення, включаючи відповідні етапи в послідовності будівництва, мають бути розглянуті.
2.3 Основні перемінні
Впливи
(1)Р Впливи мають бути отримані з відповідних розділів EN 1991.
2.3.2. Розрахункові значення впливів
(1)Р Часткові коефіцієнти впливів необхідно брати з EN 1990.
(2) Часткові коефіцієнти повзучості та усадки елементів з бетону в кам’яних конструкціях мають бути отримані з
EN 1992-1-1.
(3) Для граничного значення експлуатаційної придатності деформації, що накладаються, необхідно представляти як розрахункові (середні) значення.
2.3.3 Властивості матеріалів та виробів
(1) Властивості матеріалів та конструктивних виробів та геометричні данні, що мають використовуватись для розрахунків, мають бути такими, що визначені у відповідних EN, hEN або ETA, крім випадків, коли інше зазначено в цьому EN 1992-1-1.
2.4 Перевірка методом часткового фактору
2.4.1 Розрахункові значення властивостей матеріалів
(1)Р Розрахункове значення властивостей матеріалу одержуємо діленням його власного значення на відповідний частковий коефіцієнт матеріалів, γ M.
2.4.2 Комбінація впливів
(1)Р Комбінація впливів має відповідати загальним правилам, викладеним в
EN 1990.
ПРИМІТКА 1 У жилих та офісних будівлях звичайно можливе спрощення комбінації навантажень, викладених в EN 1990
ПРИМІТКА 2 У звичайному житлі та офісних конструкціях навантаження, що накладаються, як говорить EN 1991-1 випуск, можуть тлумачитись як якийсь визначений перемінний вплив (а саме, рівномірне навантаження на всі прольоти, або нульове, де доречно), для якого коефіцієнти послаблення надаються в EN 1991-1 випуск.
2.4.3 Крайні граничні стани
(1)Р Відповідними значеннями часткового коефіцієнту матеріалів γ M повинні користуватися для крайнього граничного стану у звичайних та випадкових ситуаціях.
Аналізуючи конструкцію на випадкові впливи, необхідно враховувати вірогідність наявності випадкового впливу.
ПРИМІТКА Чисельні значення, що позначені символом γ M для користування в країні, можна знайти в Національному Додатку. Рекомендовані значення, подані як класи, що можуть відноситись до виробничого контролю (дивись також Додаток А) згідно національного вибору, приведені в таблиці нижче.
| Foreword
This document EN 1996-1 -1 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 May 2006, and conflicting national standards shall be withdrawn at the latest by March 2010
CEN/TC 250 is responsible for all Structural Eurocodes.
This document supersedes ENV 1996-1-1: 1995 and ENV 1996-1-3: 1998.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: 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 the United Kingdom.
Background to 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).
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).
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 J: 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.
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 №1 — Mechanical resistance and stability — and Essential Requirement №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 b\ CEN Technical Committees and or EOT A Working Groups working on product standards with a view to achieving full compatibility of these technical specifications with the Eurocodes.
2) According to Article 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 Article 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 snd of proof, technical rules for project design, etc.;
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.
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 (informative)
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, 1. 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 harmonised technical specifications (ENs and ETAs) for products
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, shall clearly mention which Nationally Determined Parameters have been taken into account.
This European Standard is Part of EN 1996 which comprises the following Parts:
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.
4) see Article 3.3 and Article 12 of the CPD, as well as clauses 4.2, 4.3.1, 4.3.2 and 5.2 of ID 1.
Part I-1 General - Rules for reinforced and unreinforced masonry
NOTE This Part combines ENV 1996-1-1 and ENV l 996-1-3
Part 1-2 General rules - Structural fire design.
Part 2 Design considerations, selection of materials and execution of masonry.
Part 3: Simplified calculation methods for unreinforced masonry structures
EN 1996-1-1 describes the Principles and requirements for safety, serviceability and durability of masoniv structures. It is based on the limit state concept used in conjunction with a partial factor method.
For the design of new structures, EN 1996-1-1 is intended to be used, for direct application, together with ENs 1990, 1991. 1992, 1993, 1994. 1995, 1997, 1998 and 1999.
EN 1996-1 -1 is intended for use by:
— committees drafting standards for structural design and related products, testing and execution standards:
— clients (e. g. for the formulation of their specific requirements on reliability levels and durability).
— designers and contractors;
— relevant authorities.
National Annex for EN 1996-1-1
This standard gives some symbols and some alternative methods for which a National value or choice needs to be given; notes under the relevant clauses indicate where national choices may have to be made. The National Standard implementing EN 1996-1-1 in a particular country should have a National Annex containing all Nationally Determined Parameters to be used for the design of buildings and civil engineering works to be constructed in that country.
National choice is allowed in EN 1996-1-1 through clauses:
- 2.4 3(1)P Ultimate limit states;
- 2.4.4(1) Serviceability limit states;
- 3.2 2(1) Specification of masonry mortar;
- 3.6.1.2(1) Characteristic compressive strength of masonry other than shell bedded;
- 3.6.2. (3), (4) Characteristic compressive strength of masonry other than shell bedded;
- 3.6.3(3) Characteristic flexural strength of masonry;
- 3 7 2(2) Modulus of elasticity;
- 3.7.4(2) Creep, moisture expansion or shrinkage and thermal expansion;
- 4.3.3(3) and (4) Reinforcing steel;
- 5.5.1.3(3) Effective thickness of masonry walls;
- 6.1.2.2(2) Slenderness ratio Ac below which creep may be ignored;
- 8.1.2 (2) Minimum thickness of wall;
- 8.5.2.2(2) Cavity walls;
- 8.5.2.3(2) Double-leaf walls;
- 8.6.2 (1) Vertical chases and recesses;
- 8.6.3 (1) Horizontal and inclined chases.
Section 1 General
1.1 Scope
1.1.1 Scope of Eurocode 6
(1)P Eurocode 6 applies to the design of buildings and civil engineering works, or parts there of, in unreinforced, reinforced, prestressed and confined masonry.
(2)P Eurocode 6 deals only with the requirements for resistance, serviceability and durability of structures. Other requirements, for example, concerning thermal or sound insulation, are not considered.
(3)P Execution is covered to the extent that is necessary to indicate the quality of the construction materials and products that should be used and the standard of workmanship on site needed to comply with the assumptions made in the design rules.
(4)P Eurocode 6 does not cover the special requirements of seismic design. Provisions related to such requirements are given in Eurocode 8 which complements, and is consistent with Eurocode 6.
(5)P Numerical values of the actions on buildings and civil engineering works to be taken into account in the design are not given in Eurocode 6. They are provided in Eurocode 1.
1.1.2 Scope of Part1-1 of Eurocode 6
(1)P The basis for the design of buildings and civil engineering works in masonry is given in this Part 1-1 of Eurocode 6, which deals with unreinforced masonry and reinforced masonry where the reinforcement is added to provide ductility, strength or improve serviceability. The principles of the design of prestressed masonry and confined masonry are given, but application rules are not provided. This Part is not valid for masonry with a plan area of less than 0, 04 m2.
(2) For those types of structures not covered entirely. for new structural uses for established materials. for newmaterials, or where actions and other influences outside normal experience have to be resisted, the principles and application rules given in this EN maу be applicable, but maу need to be supplemented.
(3) Part I-I gives detailed rules which are mainly applicable to ordinary buildings. The applicability of these rules may be limited, for practical reasons or due to simplifications; any limits of applicability are given in the text where necessary.
(4) The following subjects are dealt with in Part 1-1:
- section 1: General.
- section 2: Basis of design;
- section 3: Materials;
- section 4: Durability;
- section 5: Structural analysis;
- section 6: Ultimate Limit State;
- section 7: Serviceability Limit State;
- section 8: Detailing;
- section 9: Execution;
(5)PPart 1-1does not cover:
- resistance to fire (which is dealt with in
EN 1996-1-2);
- particular aspects of special types of building (for example, dynamic effects on tall buildings);
- particular aspects of special types of civil engineering works (such as masonry bridges, dams, * chimneys or liquid-retaining structures);
- particular aspects of special types of structures (such as arches or domes);
- masonry where gypsum, with or without cement, mortars are used;
- masonry where the units are not laid in a regular pattern of courses (rubble masonry);
- masonry reinforced with other materials than steel..
1.1.3 Further Parts of Eurocode 6
(1) Part 1-1of Eurocode 6will be supplemented by further Parts as follows;
Part 1-2: General rules - Structural fire design.
Part 2: Design, selection of materials and execution of masonry.
Part 3: Simplified calculation methods for unreinforced masonry structures
1.2 Normative references
1.2.1 General
(1)P This European standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the 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).
1.2.2 Reference standards
The following standards are referenced in this EN 1996-1-1:
— EN 206-1, Concrete —Part 1: Specification, performance, production and conformity:
— 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 masonry units;
— EN 772-1, Methods of test for masonry units —Part 1: Determination of compressive strength;
— EN 845-1, Specification for ancillary components for masonry — Part J: Ties, tension straps, hangers and brackets;
— EN 845-2, Specification for ancillary components for masonry —Part 2: Lintels;
— EN 845-3, Specification for ancillary components for masonry — Part 3: Bed joint reinforcement of steel meshwork;
— EN 846-2, Methods of test for ancillary components for masonry — Part 2: Determination of bond strength of prefabricated bed joint reinforcement in mortar joints;
— 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 I015-I l. Methods of test for mortar for masonry — Part 11: Determination of flexural and compressive strength of hardened mortar:
— EN 1052-1, Methods of test for masonry — Part I: Determination of compressive strength:
— EN 1052-2. Methods of test for masonry — Part 2: Determination of flexural strength:
— EN 1052-3, Methods of test for masonry —Part 3: Determination of initial shear strength:
— EN 1052-4. Methods of test for masonry — Part 4: Determination of shear strength including damp proof course;
— EN 1052-5. Methods of test for masonry — Part 5: Determination of bond strength by bond wrench method:
— EN 1990, Basis of structural design:
— EN 1991, Actions on structures:
— EN 1992. Design of concrete structures;
— EN 1993, Design of steel structures;
— EN 1994, Design of composite steel and concrete structures;
— EN 1995. Design of timber structures:
— EN 1996-2. Design, selection of materials and execution of masonry;
— EN 1997 Geotechnical design;
— EN 1999, Design of aluminium structures;
— EN 10080, Steel for the reinforcement of concrete - Weldable reinforcing steel;
— prEN 10138, Prestressing steels;
— EN ISO 1461, Hot dip galvanized coatings on fabricated iron and steel articles —Specifications and test methods.
1.3 Assumptions
(1)P The assumptions given in 1.3 of EN 1990: 2002 apply to this EN 1996-1-1.
1.4 Distinction between principles and application rules
(1)P The rules in 1.4 of EN 1990: 2002 apply to this EN 1996-1-1.
1.5 Terms and Definitions
1.5.1 General
(1) The terms and definitions given in EN 1990: 2002. Clause 1.5. apply to this EN 1996-1-1
(2) The terms and definitions used in this EN 1996-1-1 are given the meanings contained in clauses 1.5.2 to 1.5.11, inclusive.
1.5.2 Terms relating to masonry
1.5.2.1
masonry
an assemblage of masonry units laid in a specified pattern and joined together with mortar
1.5.2.2
unreinforced masonry
masonry not containing sufficient reinforcement so as to be considered as reinforced masonry
1.5.2.3
reinforced masonry
masonry in which bars or mesh are embedded in mortar or concrete so that all the materials act together in resisting action effects
1.5.2.4
prestressed masonry
masonry in which internal compressive stresses have been intentionally induced by tensioned reinforcement
1.5.2.5
confined masonry
masonry provided with reinforced concrete or reinforced masonry confining elements in the vertical and horizontal direction
1.5.2.6
masonry bond
disposition of units in masonry in a regular pattern to achieve common action
1.5.3 Terms relating to strength of masonry
1.5.3.1
characteristic strength of masonry
value of the strength of masonry having a prescribed probability of 5% of not being attained in a hypothetically unlimited test series. This value generally corresponds to aspecified fractile of the assumed statistical distribution of the particular property of the material or product in a test series. A nominal value is used as the characteristic value in some circumstances
1.5.3.2
compressive strength of masonry
the strength of masonry in compression without the effects of platen restraint, slendemess or eccentricity of loading
1.5.3.3
shear strength of masonry
the strength of masonry subjected to shear forces
1.5.3.4
flexural strength of masonry
the strength of masonry in bending
1.5.3.5
anchorage bond strength
the bond strength, per unit surface area, between reinforcement and concrete or mortar, when the reinforcement is subjected to tensile or compressive forces
1.5.3.6
adhesion
the effect of mortar developing a tensile and shear resistance at the contact surface of masonry units
1.5.4 Terms relating to masonry units
1.5.4.1
masonry unit
a preformed component, intended for use in masonry construction
1.5.4.2
groups 1, 2, 3 and 4 masonry units
group designations for masonry units, according to the percentage size and orientation of holes in the units when laid
1.5.4.3
bed face
the top or bottom surface of a masonry unit when laid as intended
1.5.4.4
frog
a depression, formed during manufacture, in one or both bed faces of a masonry unit
1.5.4.5
hole
a formed void which may or may not pass completely through a masonry unit
1.5.4.6
griphole
a formed void in a masonry unit to enable it to be more readily grasped and lifted with one or both hands or by machine
1.5.4.7
web
the solid material between the holes in a masonry unit
1.5.4.8
shell
the peripheral material between a hole and the face of a masonry unit
1.5.4.9
gross area
the area of a cross-section through the unit without reduction for the area of holes, \oids and re-entrants
1.5.4.10
compressive strength of masonry units
the mean compressive strength of a specified number of masonry units (see EN 771-1 to EN 771-6)
1.5.4.11
normalized compressive strength of masonry units
the compressive strength of masonry units converted to the air dned compressive strength of an equivalent 100 mm wide x 100 mm high masonry unit (see EN 771-1 to EN 771-6)
1.5.5 Terms relating to mortar
1.5.5.1
masonry mortar
mixture of one or more inorganic binders, aggregates and water, and sometimes additions and/or admixtures, for bedding, jointing and pointing of masonry
1.5.5.2
general purpose masonry mortar
masonry mortar without special characteristics
1.5.5.3
thin layer masonry mortar
designed masonry mortar with a maximum aggregate size less than or equal to a prescnbed figure
NOTE: See note in 3.6.1.2 (2)
1.5.5.4
lightweight masonry mortar
designed masonry mortar with adry hardened density below aprescribed figure according to EN 998-2
1.5.5.5
designed masonry mortar
a mortar whose composition and manufacturing method is chosen in order to achieve specified properties (performance concept)
1.5.5.6
prescribed masonry mortar
mortar made in predetermined proportions, the properties of which are assumed from the stated proportions of the constituents (recipe concept)
1.5.5.7
factory made masonry mortar
mortar batched and mixed in afactory
1.5.5.8
semi-finished factory made masonry mortar
prebatched masonry mortar or a premixed lime and sand masonry mortar
1.5.5.9
prebatched masonry mortar
mortar whose constituents are wholly batched in a factory, supplied to the building site and mixed there according to the manufacturers' specification and conditions
1.5.5.10
premixed lime and sand masonry mortar
mortar whose constituents are wholly batched and mixed in a factory, supplied to the building site, where further constituents specified or provided by the factory are added (e. g. cement) and mixed with the lime and sand
1.5.5.11
site-made mortar
a mortar composed of individual constituents batched and mixed on the building site
1.5.5.12
compressive strength of mortar
the mean compressive strength of a specified number of mortar specimens after curing for 28 davs
1.5.6 Terms relating to concrete infill
1.5.6.1
concrete infill
a concrete used to fill pre-formed cavities or voids in masonry
1.5.7 Terms relating to reinforcement
1.5.7.1
reinforcing steel
steel reinforcement for use in masonry
1.5.7.2
bed joint reinforcement
reinforcing steel that is prefabricated for building into a bed joint
1.5.7.3
prestressing steel
steel wires, bars or strands for use in masonry
1.5.8 Terms relating to ancillary components
1.5.8.1
damp proof course
a layer of sheeting, masonry units or other material used in masonry to resist the passage of water
1.5.8.2
wall tie
a device for connecting one leaf of a cavity wall across a cavity to another leaf or to a framed structure or backing wall
1.5.8.3
strap
a device for connecting masonry members to other adjacent components, such as floors and roofs
1.5.9 Terms relating to mortar joints
1.5.9.1
bed joint
a mortar layer between the bed faces of masonry units
1.5.9.2
perpend joint (head joint)
a mortar joint perpendicular to the bed joint and to the face of wall
1.5.9.3
longitudinal joint
a vertical mortar joint within the thickness of a wall, parallel to the face of the wall
1.5.9.4
thin layer joint
a joint made with thin layer mortar
1.5.9.5
jointing
the process of finishing a mortar joint as the work proceeds
1.5.9.6
pointing
the process of filling and finishing mortar joints where the surface of the joint has been raked out or left open for pointing
1.5.10 Terms relating to wall types
1.5.10.1
load-bearing wall
a wall primarily designed to carry an imposed load in addition to its own weight
1.5.10.2
single-leaf wall
a wall without a cavity or continuous vertical joint in its plane
1.5.10.3
cavity wall
a wall consisting of two parallel single-leaf walls, effectively tied together with wall ties or bed joint reinforcement. The space between the leaves is left as a continuous cavity or filled or partially filled with non-loadbearing thermal insulating material
NOTE: A wall consisting of two leaves separated b\ a cavity, where one of the leaves is not contributing to the strength or stiffness of the other (possibly loadbearing leaf, is to be regarded as a veneer wall.
1.5.10.4
double-leaf wall
a wall consisting of two parallel leaves with the longitudinal joint between filled solidly with mortar and securely tied together with wall ties so as to result in common action under load
1.5.10.5
grouted cavity wall
a wall consisting of two parallel leaves with the cavity filled with concrete or grout and securely tied together with wall ties or bed joint reinforcement so as to result in common action under load
1.5.10.6
faced wall
a w all with facing units bonded to backing units so as to result in common action under load
1.5.10.7
shell bedded wall
a wall in which the masonry units are bedded on two or more strips of mortar two of which are at the outside edges of the bed face of the units
1.5.10.8
veneer wall
a wall used as a facing but not bonded or contributing to the strengtii of the backing wall or framed structure
1.5.10.9
shear wall
a wall to resist lateral forces in its plane
1.5.10.10
stiffening wall
a wall set perpendicular to another wall to give it support against lateral forces or to resist buckling and so to provide stability to the building
1.5.10.11
non-loadbearing wall
a wall not considered to resist forces such that it can be removed without prejudicing the remaining integrity of the structure
1.5.11 Miscellaneous terms
1.5.11.1
chase
channel formed in masonry
1.5.11.2
recess
indentation formed in the face of a wall
1.5.11.3
grout
a pourable mixture of cement, sand and water for filling small voids or spaces
1.5.11.4
movement joint
a joint permitting free movement in the plane of the wall
1.6 Symbols
(1) Material-independent symbols are given in 1.6 of EN 1990.
(2) Material-dependent symbols used in this EN 1996-1-1 are:
Latin letters
a 1 distance from the end of a wall to the nearest edge of a loaded area;
a x distance from the face of a support to the cross-section being considered;
A loaded horizontal gross cross-sectional area of a wall;
A efeffective area of bearing;
A scross-sectional area of steel reinforcement;
A sw area of shear reinforcement;
b width of a section;
b c width of the compression face midway between restraints;
b ef effective width of a flanged member;
b ef.1 effective width of a flanged member;
b ef.teffective thickness of a flanged member;
c nomnominal concrete cover;
d effective depth of a beam;
d adeflection of an arch under the design lateral load;
d с largest dimension of the cross section of a core in me direction of bending;
e cadditional eccentricity;
e he eccentricity at the top or bottom of a wall, resulting from horizontal loads;
e hmeccentricity at the middle of a wall, resulting from horizontal loads;
e ieccentricity at the top or the bottom of a wall;
e initinitial eccentricity;
e k eccentricity due to creep;
e meccentricity due to loads.
e mk eccentricity at the middle of the wall;
E short term secant modulus of elasticity of masonry;
E longterm long term modulus of elasticity of masonry;
En modulus of elasticity of member n;
f bnormalised mean compressive strength of a masonry unit;
f bod design anchorage strength of reinforcing steel;
f bok characteristic anchorage strength;
f ckcharacteristic compressive strength of concrete infill;
f cvkcharacteristic shear strength of concrete infill;
f ddesign compressive strength of masonry in
the direction being considered;
f kcharacteristic compressive strength of masonry;
f mcompressive strength of masonry mortar;
f vddesign shear strength of masonry;
f vkcharacteristic shear strength of masonry;
f vkocharacteristic initial shear strength of masonry, under zero compressive stress;
f vltlimit to the value of fvk ;
f xd f vlt design flexural strength appropriate to the plane of bending;
f xd1design flexural strength of masonry having the plane of failure parallel to the bed joints;
f xd1, app apparent design flexural strength of masonry having the plane of failure parallel to the bed joints;
f xk1 characteristic flexural strength of masonry having a plane of failure parallel to the bed
joints
f xd2 design flexural strength of masonry having the plane of failure perpendicular to the bed joints
f xd2, app apparent design flexural strength of masonry having the plane of failure perpendicular to the bed joints;
f xk2 characteristic flexural strength of masonry having a plane of failure perpendicular
to the bed joints;
f yd design strength of reinforcing steel;
f yk
Fd characteristic strength of reinforcing steel
design compressive or tensile resistance of a wall tie;
g total of the widths of mortar strips;
G shear modulus of masonry;
h clear height of a masonry wall;
h i clear height of masonry wall, i;
hef effective height of a wall;
h tot total height of a structure, from the top of the foundation, or a wall, or a core;
h c height of a wall to the level of the load;
I j second moment of area of member, j;
k ratio of the lateral load capacity of a vertically spanning wall to the lateral load capacity of the actual wall area, taking possible edge restraint into account;
k m ratio of slab stiffness to wall stiffness
k rrotational stiffness of a restraint;
K constant used in the calculation of the compressive strength of masonry;
l length of a wall (between other walls, between a wall and an opening, or between openings);
l bstraight anchorage length
lc length of the compressed part of a wall
l clclear length of an opening
l ef effective span of a masonry beam:
l efmeffective length of a bearing at mid height of a wall;
l rclear distance between lateral restraints:
l athe length or the height of the wall between supports capable of resisting an arch thrust;
M adadditional design moment;
M d design bending moment at the bottom of a core;
M iend moment at node, i;
M id design value of the bending moment at the top or the bottom of the wall;
M mddesign value of the greatest moment at the middle of the height of the wall;
M Rddesign value of the moment of resistance;
M Eddesign value of the moment applied;
M Edu design value of the moment above a floor;
M Edfdesign value of the moment below a floor;
n number of storeys
n istiffness factor of members;
n tnumber of wall ties or connectors per m2 of wall;
n tminminimum number of wall ties or connectors per m2 of wall;
N sum of the design vertical actions on a building;
N adthe maximum design arch thrust per unit
length of wall;
N iddesign value of the vertical load at the top or bottom of a wall or column;
N mddesign value of the vertical load at the middle of the height of a wall or column;
N Rddesign value of the vertical resistance of a masonry wall or column;
N Rdc design value of the vertical concentrated load resistance of a wall;
N Eddesign value ofthe vertical load
N Edfdesign value of the load out of a floor
N Edu design value of the load above the floor
N Elload applied by a floor
N Edcdesign value of a concentrated vertical load
q lat, ddesign lateral strength per unit area of wall
Q d design value of the total vertical load, in the part of a building stabilised by a core
r arch rise
Re yield stress of steel
s spacing of shear reinforcement
E ddesign value of the load applied to a reinforced masonry member
t thickness of a wall
t ch, v maximum depth of a vertical chase or recess without calculation
t ch, hmaximum depth of a horizontal or inclined chase
t i thickness of wall i
t minminimum thickness of a wall
t efeffective thickness of a wall
t fthickness of a flange
t rithickness of the rib, i
V Eddesign value of a shear load
V Rddesign value of the shear resistance
wi uniformly distributed design load, i
W Ed design lateral load per unit area
x depth to the neutral axis
z lever arm;
Z elastic section modulus of a unit height or length of the wall
Greek letters
α angle of shear reinforcement to the axis of the beam
α tcoefficient of thermal expansion of masonry
α 1, 2bending moment coefficients
β enhancement factor for concentrated loads
χ magnification factor for the shear resistance of reinforced walls;
δ factor used in the determination of the normalised mean compressive strength of masonry units;
ε c∞ final creep strain of masonry;
ε elelastic strain of masonry;
ε mulimiting compressive strain in masonry
ε sy yield strain of reinforcement;
ø effective diameter of the reinforcing steel;
ø ∞ final creep coefficient of masonry;
Φ reduction factor;
Φ flreduction factor, taking the influence of the flexural strength into account;
Φ ireduction factor at the top or bottom of the wall;
Φ m reduction factor within the middle height of the wall;
Υ M partial factor for materials, including uncertainties about geometry and modeling;
η factor for use in calculating the out-of-plane eccentricity of loading on walls;
λ xdepth of the compressed zone in a beam, when using a rectangular stress block;
λ cvalue of the slenderness ratio up to which eccentricities due to creep can be neglected;
μ orthogonal ratio of the flexural strengths of masonry;
ξ magnification factor for the rotational stiffness of the restraint of the structural element being considered;
ρ ddry density:
ρ nreduction factor;
ρ tstiffness coefficient;
σ ddesign compressive stress;
υ angle of inclination to the vertical of the structure.
Section 2 Basis of design
2.1 Basic requirements
2.1.1 General
(1) P The design of masonry structures shall be in accordance with the general rules given in EN 1990.
(2) P Specific provisions for masonry structures are given in this section and shall be applied
(3) The basic requirements of EN 1990 Section 2 are deemed to be satisfied for masonry structures when the following are applied:
— limit state design in conjunction with the partial factor method described in EN 1990;
— actions given in EN 1991;
— combination rules given in EN 1990;
— the principles and rules of application given in this EN 1996-1-1.
2.1.2 Reliability
(1)P The reliability required for masonry structures will be obtained by carrying out design according to this EN 1996-1-1.
2.1.3 Design working life and durability
(1) For the consideration of durability reference should be made to Section 4.
2.2 Principles of limit state design
(1) P Limit states may concern only the masonry, or such other materials as are used for parts of the structure, for which reference shall be made to relevant Parts of EN 1992, EN 1993, EN 1994, EN 1995 and EN 1999.
(2) P For masonry structures, the ultimate limit state and serviceability limit state shall be considered for all aspects of the structure including ancillary components in the masonry.
(3)P For masonry structures, all relevant design solutions including relevant stages in the sequence of construction shall be considered.
2.3 Basic variables
2.3.1 Actions
(1)P Actions shall be obtained from the relevant Parts of EN 1991.
2.3.2 Design values of actions
trail properties
(1) P Partial factors for actions should be obtained from EN 1990.
(2) Partial factors for creep and shrinkage of concrete elements in masonry structures should be obtained from EN 1992-1-1.
(3) For serviceability limit states, imposed deformations should be introduced as estimated (mean) values.
2.3.3 Material and product properties
(1) Properties of materials and construction products and geometrical data to be used for design should be those specified in the relevant ENs, hENs or ETAs. unless otherwise indicated in this EN 1996-1-1.
2.4 Verification by the partial factor method
2.4.1 Design values of ma
(1)P The design value for a material property is obtained by dividing its characteristic value by the relevant partial factor for materials, γ M.
2.4.2 Combination of actions
(1)P Combination of actions shall be in accordance with the general rules given in
EN 1990.
NOTE 1 In residential and office structures, it will usually be possible to simplify the load combinations given in EN 1990.
NOTE 2 In normal residential and office structures the imposed loads, as given in the EN 1991-1 series, may be treated as one fixed variable action (that is, equal loading on all spans, or zero, when appropriate) for which reduction factors are given in the EN 1991-1 series.
2.4.3 Ultimate limit states
(1)P The relevant values of the partial factor for materials γ M shall be used for the ultimate limit state for ordinary and accidental situations. When analysing the structure for accidental actions, the probability of the accidental action being present shall be taken into account.
NOTE The numerical values to be ascribed to the symbol γ M for use in a country may be found in its National Annex. Recommended values, given as classes that may be related to execution control (see also Annex A) according to national choice, are given in the table below
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