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Допустимі відхилення
(1)Р Всі роботи проводять відповідно до технічної документації в межах допустимих відхилень.
(2) Розміри і площинність перевіряють по ходу роботи.
(3) Відхилення елементів кам'яних конструкцій від проектного положення не повинні перевищувати значень, наведених в технічних вимогах на проектування. Якщо значення відхилень, встановлених в згідно таблиці 3.1, не наведено в технічних вимогах на проектування, допуски на площинність або кутові допуски і відповідні допустимі відхилення мають бути менш:
— значень, наведених в таблиці 3.1, також (див. рисунок 3.1);
— практичних значень, прийнятих в межах певної місцевості.
ПРИМІТКА. Практика, прийнята в межах певної місцевості, може бути наведена в несуперечливій додатковій інформації і на неї наводиться посилання в національному додатку.
| 1 General
1.1 Scope of Part 2 of Eurocode 6
(1)P The scope of Eurocode 6 for Masonry Structures as given in 1.1.1 of EN 1996-1-1: 2005 applies also to this EN 1996-2.
(2)P EN 1996-2 gives basic rules for the selection of materials and execution of masonry to enable it to comply with the design assumptions of the other parts of Eurocode 6. With the exception of the items given in 1.1(3)P, the scope of Part 2 deals with ordinary aspects of masonry design and execution including:
— the selection of masonry materials;
— factors affecting the performance and durability of masonry;
— resistance of buildings to moisture penetration;
— storage, preparation and use of materials on site;
— the execution of masonry;
— masonry protection during execution;
NOTE 1. Where general guidance only is given, additional guidance based on local conditions and practice may be made available in non contradictory complementary documents which may be referred to in the National Annex.
NOTE 2. The scope of Eurocode 6 excludes seismic, thermal and acoustic functional performance of masonry structures.
(3)P EN 1996-2 does not cover the following items:
— those aspects of masonry covered in other parts of Eurocode 6;
— aesthetic aspects;
— applied finishes;
— health and safety of persons engaged in the design or execution of masonry;
— the environmental effects of masonry buildings, civil engineering works and structures on their surroundings.
1.2 Normative references
(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 applies (including amendments).
— EN 206-1, Concrete -Part 1: Specification, performance, production and conformity
— EN 771 (all parts), Specification for masonry units
— EN 998-2, Specification for mortar for masonry – Part 2: Masonry mortar
— EN 845 (all parts), Specification for ancillary components for masonry
— EN 1015-11, Methods of test for mortar for masonry — Part 11: Determination of flexural and compressive strength of hardened mortar
— EN 1015-17, Methods of test for mortar for masonry – Part 17: Determination of water-soluble chloride content of fresh mortars
— EN 1052 (all parts), Methods of test for masonry
— EN 1990, Eurocode: Basis of structural design
— EN 1996-1-1, Eurocode 6: Design of masonry structures — Part 1: General rules for reinforced and unreinforced masonry structures
— EN 13914-1, The design, preparation and application of external rendering and internal plastering — Part 1: External rendering
1.3 Assumptions
(1)P In addition to the assumptions given in 1.3 of EN 1990: 2002 the following assumptions apply in this EN 1996-2:
— Design shall be in accordance with Section 2 taking into account Section 3.
— Execution shall be in accordance with Section 3 taking into account Section 2.
(2) The design Principles are valid only when the Principles for execution in Section 3 are complied with.
1.4 Distinction between Principles and Application Rules
(1)P The rules in 1.4 of EN 1990: 2002 apply to this EN 1996-2.
1.5 Definitions
1.5.1 General
(1) The terms and definitions given in 1.5 of EN 1990: 2002 apply to this EN 1996-2.
(2) The terms and definitions used in EN 1996-1-1 apply to this EN 1996-2.
(3) Additional terms and definitions used in this EN 1996-2 are given the meanings contained in 1.5.2 to 1.5.5, inclusive.
1.5.2 Terms and definitions relating to communication of design
1.5.2.1 design specification
documents describing the designer's requirements for the construction, including drawings, schedules, test reports, references to parts of other documents and written instructions.
1.5.3 Terms relating to climatic factors and exposure conditions
1.5.3.1 macro conditionsclimatic factors depending on the general climate of the region in which a structure is built, modified by the effects of local topography and/or other aspects of the site.
1.5.3.2 micro conditionslocalised climatic and environmental factors depending on the position of a masonry element within the overall structure and taking into account the effect of protection, or lack of protection, by constructional details or finishes.
1.5.4 Term relating to masonry units
1.5.4.1 accessory masonry unit
a masonry unit which is shaped to provide a particular function, e.g. to complete the geometry of the masonry.
1.5.5 Other terms
1.5.5.1 applied finish
a covering of material bonded to the surface of the masonry.
1.5.5.2 cavity width
the distance perpendicular to the plane of the wall between the cavity faces of the masonry leaves of a cavity wall or that between the cavity face of a veneer wall and the masonry backing structure.
1.5.5.3 cladding
a covering of material(s) fastened or anchored in front of the masonry and not in general bonded to it.
1.6 Symbols
(1)P For the purpose of this standard the symbols in accordance with 1.6 of EN 1996-1-1: 2005 apply.
(2)P Other symbols used in this EN 1996-2 are:
dp — minimum depth for pointing
lm — maximum horizontal distance between vertical movement joints in external non-loadbearing walls.
2 Design considerations
2.1 Factors affecting the durability of masonry
2.1.1 General
(1)P Masonry shall be designed to have the performance required for its intended use.
2.1.2 Classification of environmental conditions
2.1.2.1 Micro conditions of exposure
(1)P The micro conditions to which the masonry is expected to be exposed shall be taken into account in the design.
(2) When deciding the micro conditions of exposure of the masonry, the effect of applied finishes, protective claddings and details should be taken into account.
(3) Micro conditions of exposure of completed masonry should be categorised into classes, as follows:
MX1 — In a dry environment;
MX2 — Exposed to moisture or wetting;
MX3 — Exposed to moisture or wetting plus freeze/thaw cycling;
MX4 — Exposed to saturated salt air or seawater;
MX5 — In an aggressive chemical environment.
NOTE When necessary, more closely defined conditions within these classes may be specified using the sub-classes in Annex A (e.g. MX2.1 or MX2.2 and M X 3.1 or M X 3.2).
(4) To produce masonry that meets specified performance criteria and withstands the environmental conditions to which it is exposed, the determination of the exposure class should take into account:
— climatic factors;
— severity of exposure to moisture or wetting;
— exposure to freeze/thaw cycling;
— presence of chemical materials that may lead to damaging reactions.
2.1.2.2 Climatic factors (macro conditions of exposure)
(1)P The effect of the macro conditions on the micro conditions shall be taken into account when determining the wetting of masonry and its exposure to freeze/thaw cycling.
(2) Concerning the macro conditions the following should be taken into account:
— rain and snow;
— the combination of wind and rain;
— temperature variation;
— relative humidity variation.
NOTE. It is acknowledged that climates (macro conditions) vary considerably throughout Europe and that certain aspects of climate can influence the risk of exposure of masonry to wetting and/or freeze/thaw cycling. However, it is the classification of the micro conditions that is relevant for determining the durability of masonry rather than the ranking of the macro conditions. Examples of relative exposure to wetting of masonry elements in a typical building are shown in Annex A.
2.1.3 Aggressive chemical environments
(1) In coastal areas the exposure of masonry to airborne chlorides or seawater should be taken into account.
(2) Possible sources of sulfates include the following:
— natural soils;
— groundwater;
— waste deposits and filled ground;
— construction materials;
— airborne pollutants.
(3) Where the presence of aggressive chemicals in the environment, other than airborne chlorides or seawater, can affect masonry, class MX5 should be assumed. Where salts can be transported by water moving through the masonry, the potential for increased concentrations and quantities of available chemicals should be taken into account.
2.2 Selection of materials
2.2.1 General
(1)P Materials, where incorporated in the works, shall be able to resist the actions to which they are expected to be exposed, including environmental actions.
(2)P Only materials, products, and systems with established suitability shall be used.
(3) Where the selection of materials for masonry is not otherwise covered in Part 2, it should be done in accordance with local practice and experience.
NOTE 1. Established suitability may result from conformity to a European Standard that is either referred to by this standard or that specifically refers to uses within the scope of this standard. Alternatively, where either there is no appropriate European Standard, or the material or product deviates from the requirements of an appropriate European Standard, established suitability may result from conformity to either:
— a Technical Approval, or
— a national standard, or
— other provisions, any of which refer specifically to uses within the scope of this standard and are accepted in the place of use of the material or product.
NOTE 2. Acceptable masonry unit specifications and mortar may be selected from Annex B, Table B.1 and B.2, in relation to durability.
2.2.2 Masonry units
(1) The requirements for masonry units should be specified in accordance with the following parts of EN 771 relating to the type of material:
— EN 771-1 for clay masonry units;
— EN 771-2 for calcium silicate masonry units;
— EN 771-3 for aggregate concrete masonry units;
— EN 771-4 for autoclaved aerated concrete masonry units;
— EN 771-5 for manufactured stone masonry units;
— EN 771-6 for natural stone masonry units.
(2) For products not in accordance with EN 771 (e.g. reclaimed products) the design specification should state the required product performance characteristics and the means of their verification including the requirements for sampling and frequency of testing.
2.2.3 Masonry mortar and concrete infill
2.2.3.1 General
(1) Masonry mortar should be selected according to the exposure condition of the masonry and the specification of the masonry units. Until a European Standard method of test for durability is available, the suitability of masonry mortars should be determined on the basis of established local experience of the performance of the particular materials and mix proportions.
2.2.3.2 Selection of factory made masonry mortar and concrete infill
(1) When factory made masonry mortar or concrete infill is considered for use in exposure classes MX4 or MX5 the manufacturer's advice should be sought as to its suitability.
NOTE. Until a European Standard method of test for durability is available, the suitability of masonry mortars conforming to EN 998-2 is based on the manufacturer's experience appropriate to the intended use.
2.2.3.3 Selection of site-made masonry mortar and concrete infill
(1) For site-made masonry mortar and concrete infill the design specification should state the
required product performance characteristics and the means of their verification including the requirements for sampling and frequency of testing. In addition, where the designer is satisfied that a prescriptive specification will provide the required performance, a detailed specification of the constituent materials, their proportions and the method of mixing may be given either on the basis of tests carried out on trial mixes and/or on the basis of authoritative publicly available references acceptable in the place of use.
(2) The guidance in 3.3.1 should be taken into account particularly where admixtures, additions and pigments are to be used.
(3) In exposure classes MX1, MX2 or MX3, the masonry mortar should be specified for durability using the terms defined in EN 998-2:
— masonry subjected to passive exposure;
— masonry subjected to moderate exposure;
— masonry subjected to severe exposure.
NOTE. 2.2.3.3(1) requires performance characteristics to be specified in all cases. For durability, 2.2.3.3(3) requires it to be done by reference to the stated terminology. It is then an option for the designer to give a prescriptive specification that will fulfil the performance requirements, or alternatively, it can be done as an execution task in accordance with 3.3.1.1(2). For general applications mortar durability designations may be selected from table B.2.
(4) When site-made masonry mortar or concrete infill is to be specified for use in exposure classes MX4 or MX5, the mix proportions to provide adequate durability for the particular conditions should be selected on the basis of authoritative publicly available references acceptable in the place of use.
(5) Where adhesion between masonry units and mortar (bond strength) is a particular design requirement, the mix proportions should take this into account.
NOTE. The manufacturer of masonry units may give advice on the type of masonry mortar to be used or tests may be carried out in accordance with relevant parts of EN 1052.
2.2.4 Ancillary components and reinforcement
(1)P Ancillary components and their fixings shall be corrosion resistant in the environment in which they are used.
NOTE 1. Annex C gives guidance on materials and corrosion protection systems for ancillary components in relation to exposure classes.
NOTE 2. Reinforcing steel should be selected following the recommendations given in 4.3.3 of EN 1996-1-1: 2005.
2.3 Masonry
2.3.1 Detailing
(1) Where the detailing of masonry is not otherwise covered in this EN 1996-2, it should be done in accordance with local practice and experience.
NOTE. The local practice and experience may be given in non-contradictory complementary information and referenced in the National Annex.
2.3.2 Joint finishes
(1) Pointing mortar should be compatible with the jointing mortar.
2.3.3 Masonry movement
(1)P The possibility of masonry movement shall be allowed for in the design such that the
performance of the masonry in use is not adversely affected by such movement.
(2) Where intersecting walls do not all have effectively similar deformation behaviour, the
connection between such walls should be able to accommodate any resulting differential movement.
(3) Movement tolerant ties should be provided where required to accommodate relative in-plane movements between masonry leaves or between masonry and other structures to which the masonry is attached.
(4) Where cavity wall ties that are not movement tolerant are used, the uninterrupted height between horizontal movement joints in the outer leaf of external cavity walls should be limited to avoid the loosening of the wall ties.
(5) Movement joints should be used, or reinforcement should be incorporated into the masonry, in order to minimise cracking, bowing or distortion caused by expansion, shrinkage, differential movements or creep.
2.3.4 Movement joints
2.3.4.1 General
(1) Vertical and horizontal movement joints should be provided to allow for the effects of thermal and moisture movement, creep and deflection and the possible effects of internal stresses caused by vertical or lateral loading, so that the masonry does not suffer damage.
(2) The position of movement joints should take into account the need to maintain structural integrity of the wall.
(3) Movement joints should be designed and positioned having regard to:
— the type of masonry unit material taking into account the moisture movement characteristics of the units;
— the geometry of the structure taking into account openings and the proportions of panels;
— the degree of restraint;
— the response of the masonry to long and short term loading;
— the response of the masonry to thermal and climatic conditions;
— fire resistance;
— sound and thermal insulation requirements;
— the presence or not of reinforcement.
(4) The detailing of a movement joint should enable the movement joint to accommodate the anticipated movements, both reversible and irreversible, without damage to the masonry.
(5) All movement joints should pass through the full thickness of the wall or the outer leaf of a cavity wall and through any finishes that are insufficiently flexible to be able to accommodate the movement.
(6) Slip planes should be designed to allow parts of the construction to slide, one in relation to the other, to reduce tensile and shear stresses in the adjacent elements.
(7) In external walls, movement joints should be designed to allow any water to flow off without causing harm to the masonry or penetrating into the building.
2.3.4.2 Spacing of movement joints
(1) The horizontal spacing of vertical movement joints in masonry walls should take into account the type of wall, masonry units, mortar and the specific construction details.
(2) The horizontal distance between vertical movement joints in external non-loadbearing unreinforced masonry walls should not exceed lm.
NOTE 1. The value for lm to be used in a Country may be found in its National Annex. Recommended values for lm for unreinforced non-loadbearing walls are given in the table:
NOTE 2. The maximum horizontal spacing of vertical movement joints may be increased for walls containing bed joint reinforcement conforming to EN 845-3. Guidance may be obtained from the manufacturers of bed joint reinforcement.
(3) The distance of the first vertical joint from a restrained vertical edge of a wall should not exceed half the value of lm.
(4) The need for vertical movement joints in unreinforced loadbearing walls should be considered.
NOTE.No recommended values for the spacing are given as they depend on local building traditions, type of floors used and other construction details.
(5) The positioning of movement joints should take into account the need to maintain structural integrity of load bearing internal walls.
(6) Where horizontal joints are required to accommodate vertical movement in an unreinforced veneer wall or in an unreinforced non-loadbearing outer leaf of a cavity wall, the spacing of horizontal movement joints should take into account the type and positioning of the support system.
2.3.5 Permissible deviations
(1) Permissible deviations of the constructed masonry from its intended position should be specified.
(2) The permissible deviations should be specifically stated as values in the design specification or in accordance with locally accepted standards.
NOTE. Compliance with tolerances is necessary in order to ensure that, despite the inevitable inaccuracies at each stage in the building process, the functional requirements are satisfied and the correct assembly of structures and components takes place without the need for adjustment or reworking. The permissible tolerances for dimensions of masonry units are specified in EN 771.
(3) Unless otherwise allowed for in the structural design, the permissible deviations should not be greater than the values given in Table 3.1. Where the design allows for deviations in excess of the values in Table 3.1, the permissible deviations should be specifically stated in the design specification.
NOTE. Table 3.1 gives the maximum deviations that have been taken into account in EN 1996-1-1.
2.3.6 Resistance to moisture penetration through external walls
(1) Where there is a need for greater resistance to moisture penetration than can be provided by the masonry alone, the application of a suitable rendering, ventilated cladding or other suitable surface treatment should be used.
NOTE. Guidance on the use of external renderings is given in EN 13914-1, The design, preparation and application of external renderings. Where a total barrier to rain penetration is required, a ventilated waterproof cladding system may be applied to the masonry.
3 Execution
3.1 General
(1)P All materials used and all work constructed shall be in accordance with the design specification.
(2)P Precautions shall be taken to ensure the overall stability of the structure or of individual walls during construction.
3.2 Acceptance, handling and storage of materials
3.2.1 General
(1)P The handling and storage of materials and masonry products for use in masonry shall be such that the materials are not damaged so as to become unsuitable for their purpose.
(2) Where required by the design specification, materials should be sampled and tested.
(3) Different materials should be stored eparately.
3.2.2 Reinforcement and prestressing materials
(1)P The surface condition of reinforcement and prestressing materials shall be examined prior to use and it shall be free from deleterious substances, which may affect adversely the steel, concrete or mortar or the bond between them.
(2) Damage or deformation of reinforcement should be avoided during storage and handling. Steel reinforcing bars, steel prestressing bars and/or tendons and prefabricated bed joint reinforcement should be clearly identified, and stored off the ground, well away from mud, oil, grease, paint or welding operations.
(3) During storage and handling of prestressing steel, welding in the vicinity of tendons without the provision of special protection (from welding splatter) should be prevented.
(4) For sheaths, the following should be taken into account:
— local damage and corrosion inside should be avoided;
— water-tightness should be ensured.
3.3 Preparation of materials
3.3.1 Site-made mortars and concrete infill
3.3.1.1 General
(1) Site-made mortars and concrete infill should be produced using a mix prescription that will result in the required performance characteristics. When the mix prescription is not given in the design specification, the detailed specification of constituent materials, their proportions and the method of mixing should be selected on the basis of tests carried out on trial mixes and/or on the basis of authoritative publicly available references acceptable in the place of use.
(2) When tests are required they should be carried out in accordance with the design specification. When test results indicate that the mix prescription is not giving the required performance characteristics, the mix prescription should be amended and if it is part of the design specification any amendments should be agreed with the designer.
3.3.1.2 Chloride content
(1) When sampled in accordance with EN 998-2, and tested in accordance with EN 1015-17 or when using a calculation method based on measured chlorine ion content of the constituents of the mortar, the maximum value permitted in EN 998-2 should not be exceeded.
3.3.1.3 Strength of mortar and concrete infill
(1) When the properties of mortar need to be verified, specimens should be prepared and tested in accordance with EN 1015-11.
(2) When the properties of concrete infill need to be verified, specimens should be prepared and tested in accordance with EN 206-1.
3.3.1.4 Admixtures and additions
(1)P Unless permitted by the design specification, admixtures, additions or pigments shall not be used.
3.3.1.5 Gauging
(1)P Materials for mortar and concrete infill shall be measured by weight or by volume into the specified proportions in clean suitable measuring devices.
(2) In the proportioning of the materials for concrete infill, account should be taken of the amount of water that will be absorbed by
the masonry units and mortar joints.
3.3.1.6 Mixing method and mixing time
(1) The mixing method and the time of mixing should ensure consistent production of the correct mix proportions. Mortar should not be contaminated during subsequent handling.
(2) Unless hand mixing is permitted by the design specification, a suitable mechanical mixer should be used.
(3) The mixing time should be counted from the time when all constituent materials have been added to the mixer. Wide variation in the mixing time of different batches should be avoided.
NOTE. In general, a machine mixing time of 3 minutes to 5 minutes after all the constituents have been added is suitable and, except in the case of retarded mortars, the mixing time should not exceed 15 minutes. Prolonged mixing where airentraining agents are used can lead to excessive air entrainment and thus to a reduction in adhesion and durability.
(4) The mortar or concrete infill should be mixed so as to have sufficient workability for it to fill the spaces into which it is placed, without segregation, when it is compacted.
3.3.1.7 Workable life of mortars and concrete infill containing cement
(1) Mortars and concrete infill containing cement should be ready for use when they are discharged from the mixer, and no subsequent additions of binders, aggregates, admixtures, or water should be made.
NOTE Water may be added to site-made mortars to replace water lost by evaporation.
(2) Mortar and concrete infill should be used before its workable life has expired. Any mortar or concrete infill left after the initial set has commenced should be discarded and should not be reconstituted.
3.3.1.8 Mixing in cold weather
(1)P Water, sand or premixed lime: sand mortars containing ice particles shall not be used.
(2) Unless specifically permitted by the design specification, de-icing salts or other antifreezing agents should not be used.
3.3.2 Factory made mortars, pre-batched mortars, pre-mixed lime sand mortars and ready mixed concrete infill
(1)P Factory made mortars and pre-batched mortars shall be used in accordance with the manufacturer's instructions, including mixing time and type of mixer.
(2) Mortar should be mixed effectively so that a uniform distribution of the constituents is ensured.
(3) The site mixing equipment, procedures, including mixing in cold weather and care of mixing plant and mixing time specified by the manufacturer, should be used.
(4) Pre-mixed lime: sand mortars should be mixed with the binder according to 3.4.3.
(5)P Ready-to-use factory made mortars shall be used before the expiry of the workable life stated by the manufacturer.
(6) Ready mixed concrete infill should be used according to the design specification.
3.4 Permissible deviations
(1)P All work shall be constructed in accordance with the specified details within permissible deviations.
(2) Dimensions and planeness should be checked as the work proceeds.
(3) Deviations of the constructed masonry from its intended position should not exceed the values given in the design specification. Where values are not given in the design specification for any of the deviations listed in Table 3.1, flatness tolerances or angular tolerances then the corresponding permissible deviations should be the lesser of:
— the values given in Table 3.1, see also Figure 3.1;
— the values in accordance with locally accepted practice.
NOTE. Such locally accepted practice can be given in non-contradictory complementary information and referenced in the National Annex.
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