Stone and reinforced masonry structures updated edition. Types of stone and reinforced masonry structures, their scope. Stone and reinforced masonry structures of residential, civil and industrial buildings. Calculation of elements of stone structures. Facing
Due to the ubiquity and availability of raw materials, durability and cost-effectiveness, natural stone structures were built back in the Stone Age. Later, hewn stone, raw brick, baked brick were used as stone structures.
Stone structures are understood as load-bearing and enclosing structures of buildings and structures, made by connecting individual stones or stone products with mortar. Many outstanding monuments of stone architecture have survived to this day: the temples of Kievan Rus of the 10th century, the Archangel Cathedral in the Moscow Kremlin of 1333, the Kremlin walls of 1367. Etc.
The desire of architects to improve designs required the development of methods for their calculation.
In 1638 Galileo was the first to determine the bearing capacity of a bent beam under the assumption that the same axial tensile force arises in it as in an axial rupture, and that at the fracture point the beam rotates around the section edge. At the end of the 18th century, Coulomb proposed the theory of calculating a stone vault. In the middle of the 19th century, the Russian engineer Pauker gave a more accurate graphical definition of the bearing capacity of a stone vault.
In 1813 In England, an iron-brick factory chimney was built, and in 1825, a tunnel under the Thames from reinforced masonry. In 1853, a large iron-brick water tank was built in Washington.
Reinforced masonry structures have also been widely used in our country in the construction of buildings with reinforced brick frames. Traditional materials and designs are widely used. Since 1955, masonry and reinforced masonry structures have been calculated according to limit states. In the development of the theory and practice of stone structures, the role of V.P. Nekrasov, L.I. Sementsova, S.V. Polyakova, Yu.M. Ivanova and others.
Application stone and reinforced masonry structures found in all climatic regions as load-bearing and enclosing structures for centrally and eccentrically compressed elements with limited eccentricity. Reinforced masonry structures are similar in properties to reinforced concrete structures.
Advantages of stone and reinforced stone structures:
Comparative cheapness and availability of the material;
High strength characteristics
Disadvantages: -high thermal conductivity;
High labor intensity;
Seasonal limitation of work;
When designing stone and reinforced masonry structures, the requirements
SNiP 11-25-80 Stone and reinforced masonry structures
Bricks and stones for stone and reinforced masonry structures are produced in the following grades: stones of low strength (light concrete and natural) - 4; 7; 15; 25; 35; 50
Stones of medium strength (brick, ceramic, natural, concrete) - 75; 100; 125; 150; 200
High strength stones (brick, natural, concrete) -250;300;400;500;600;800;1000
For mortars, grades-4; 10; 25; 50; 75; 100; 150; 200 are established. Grades 150 and 200 are used for free-standing and most loaded elements. Solutions with a density (in a dry state) of 1500 kg / m3 or more are called heavy, up to light.
Frost resistance grades F 10-300, depending on the building class and operation mode, design grades 15-50
For reinforcement, the following classes of reinforcement are used: for mesh-A-1; VR-1; for longitudinal and transverse reinforcement, anchors, ties-A-1; A-11; Vr-1
Application: for laying external walls with dry and normal humidity conditions, it is recommended to use solid masonry made of hollow bricks, ceramic and lightweight concrete stones, with wet conditions, provided that the inner surface is protected by vapor barrier, with wet conditions, and for external walls of basements and plinths is not allowed. Solid ceramic bricks and stones made of heavy concrete are used for solid masonry in basements, basement walls, and in the walls of unheated buildings. Brick grades 150 and more are used in buildings over five floors high. Sand-lime brick is not used for laying basement walls, and in wet and damp conditions.
Strength and deformation characteristics of masonry
The strength and deformability of masonry depends on many factors:
From the strength and deformability of stone and mortar
The size and shape of the stone
Mobility of the solution and the degree of filling of vertical joints with it
masonry quality
Mason qualifications, etc.
The strength of stone materials is determined by the results of tests of reference samples for compression. The brick is additionally tested for bending. The compressive strength of the stone is 10-15 times higher than the tensile strength. According to the compressive strength, the brand of brick is established.
Stone materials are brittle, mortars in the hardened state are elastic-plastic. Masonry, the bearing capacity of which is provided by the joint work of these materials, is a non-linearly deformable material. When the masonry perceives compressive forces, the transverse deformations of mortars in horizontal joints significantly exceed the transverse deformations of stone materials, therefore, the masonry collapses from tensile forces in the stone arising under the influence of transverse deformations of the mortar. An increase in the thickness of the seam leads to a decrease in the strength of the masonry. The destruction of the masonry begins with the opening of vertical joints and the appearance of small vertical cracks in individual stones. With further loading, vertical cracks join in height and dismember the masonry into separate pillars, then with a further increase in load, the masonry loses its stability.
The strength and deformation characteristics of the masonry are obtained by testing prismatic samples with a base size of 38 * 38; 51*51 cm. height 110-120 cm.
Strength characteristics of masonry:- temporary compressive strength R and
Design resistance to axial compression R
Design resistance to axial tension R bl
Design bending tensile strength R tb
Design shear strength R sq
Deformative characteristics of masonry: - modulus of elasticity of masonry (initial modulus of deformation) E o
Elastic characteristic of masonry α
Masonry deformation modulus E
Masonry creep coefficient γ cr
Linear expansion coefficient α t
Friction coefficient μ
R value and determined from test data.
R value= R and /k, where k is a coefficient depending on the type of stone; for stone and brick of all kinds, rubble, rubble concrete k=2; for large and small blocks of cellular concrete k=2.25 (R data are given in SNiP 11-22-81).
When assigning the design resistance of the masonry to compression, the coefficient of working conditions is taken into account: γ c - for summer masonry; γ cl - for winter masonry made by freezing
(SNiP 11-22-81 v.33)
The value of R bl ; R sq ; R tb depend on the type of section along which the destruction of the masonry occurs. At the same time, it is possible two cases of destruction:- along the unbandaged section, which are the horizontal seams of the masonry
According to the tied section, which are the vertical seams of the masonry, in these cases the section has a stepped shape
The values of R tb R sq R bl are given in SNiP 11-22-81 v. 10
The value of E o under short-term loading is taken equal to E o = α tgφ o, is also proportional to the temporary resistance of axial compression E o = α R and
The value of the elastic characteristic α, depending on the type of masonry, for the main types of masonry is in SNiP 11-22-81
When calculating masonry to the action of permanent and long-term loads taking into account creep, the modulus of elasticity is reduced by the creep coefficient γ cr, taken: 1.2 - for ceramic brick masonry; 1.8 - for ceramics. stones with vertical slit voids; 2.8-for masonry of large blocks; 3-for masonry of silicate bricks and concrete blocks with porous aggregates.
E= value tgφ is the tangent of the slope of the tangent to the curve at a point with a given stress level. The modulus of deformation is used in calculations for groups 1 and 11 of the limit states of stone structures. Working in structures together with structural elements made of other materials, while E = 0.5E o
When determining masonry deformations in statically indeterminate frame systems
The moduli of elasticity and deformation of masonry made of natural stones are taken according to the results of experimental studies.
Relative deformation taking into account creep: ε=νσ/ E o, where ν-coefficient, taking into account the effect of masonry creep; σ-stress in masonry under long-term loading.
Moscow 1995
Developed by the Central Research Institute of Building Structures (TsNIISK) named after. V.A. Kucherenko Gosstroy of the USSR.
With the entry into force of this chapter of SNiP, the chapter of SNiP 11-6.2-71 “Stone and reinforced masonry structures. Design standards".
Editors - engineers F.M. Shlemin, G.M. Khorin(Gosstroy of the USSR) and candidates of tech. Sciences V.A. Kameiko, A.I. Rabinovich(TsNIISK named after V.A. Kucherenko).
At the end of the document, there is a change to SNiP II-22-81, approved by the Decree of the USSR Gosstroy of September 11, 1985 No. 143.
When using a regulatory document, one should take into account the approved changes in building codes and standards and state standards published in the Bulletin of Construction Equipment magazine and the State Standards information index of Gosstandart Russia.
1. General Provisions
1.1. The norms of this chapter must be observed when designing stone and reinforced masonry structures of new and reconstructed buildings and structures.
1.2. When designing stone and reinforced masonry structures, design solutions, products and materials should be used:
a) external walls made of: hollow ceramic and concrete stones and bricks; lightweight brickwork with slab insulation or backfill of porous aggregates; solid stones and concrete blocks on porous aggregates, porous and cellular concrete. The use of solid masonry of solid clay or silicate bricks for the outer walls of rooms with dry and normal humidity conditions is allowed only if it is necessary to ensure their strength;
b) walls made of panels and large blocks made of various types of concrete, as well as bricks or stones;
c) bricks and stones of compressive strength grades of 150 or more in buildings with a height of more than five floors;
d) local natural stone materials;
e) solutions with antifreeze chemical additives for winter masonry, taking into account the instructions of Sec. 7.
Note. With appropriate justification, it is allowed to apply design solutions, products and materials not provided for in this paragraph.
1.3. Application of silicate bricks, stones and blocks; stones and blocks from cellular concrete; hollow bricks and ceramic stones; clay brick semi-dry pressing is allowed for the outer walls of premises with a wet regime, provided that a vapor barrier coating is applied to their inner surfaces. The use of these materials for the walls of rooms with a wet regime, as well as for the outer walls of basements and plinths, is not allowed. The humidity regime of the premises should be taken in accordance with the chapter of SNiP on building heat engineering.
1.4. The strength and stability of structures and their elements must be ensured during the construction and. operation, as well as during transportation and installation of elements of prefabricated structures.
1.5 . When calculating structures, one should take into account the reliability factors Ud, taken in accordance with the Rules for Accounting for the Degree of Responsibility of Buildings and Structures in the Design of Structures. approved by the State Construction Committee of the USSR.
1.6. When designing buildings and structures, measures should be taken to ensure the possibility of their construction in winter conditions.
stone materials. As stone materials for masonry, piece stones weighing no more than 40 kg and stone products manufactured in the factory, the mass of which is limited by the carrying capacity of transport and installation equipment, are used. Piece stone materials include: ceramic bricks, ceramic stones, regular-shaped natural stones and rubble (irregularly shaped), concrete stones. Stone products are produced in the form of concrete blocks for various purposes, blocks made of bricks and ceramic stones, vibrating panels made of bricks, blocks made of natural stones, etc.
Stone materials are classified: by origin: a) natural stones mined in stone quarries (stone blocks, rubble); b) artificial stones made by firing (brick, ceramic stones), and non-fired stones (silicate brick, slag brick, concrete stones from heavy and light concrete); by structure: a) solid brick and solid stones; b) hollow brick and stones with voids of various shapes.
For manual masonry, bricks of the following types are used: ceramic ordinary plastic and semi-dry pressing, ceramic hollow plastic pressing, silicate brick, brick made of tripoli and diatomites.
Ceramic solid and silicate bricks are used for laying load-bearing walls and pillars; ceramic hollow - for laying the outer walls of heated buildings. Ceramic and concrete stones are used in the construction of walls and partitions, and large blocks of heavy concrete are also used for laying foundation walls.
Natural stones from heavy rocks (limestone, sandstone, granite) are mainly used for wall cladding and laying foundations, and walls are erected from light rocks (tuff, limestone, shell rock) in some areas.
The main characteristic of stone materials used in load-bearing structures is their strength, characterized by a grade, which indicates the tensile strength of the samples in compression.
Fittings. For reinforcement of stone structures, the following should be used: as mesh reinforcement - hot-rolled round steel of class A-1 or reinforcing wire of a periodic profile of class Vr-1 with a diameter of 3 ... 8 mm, as longitudinal and transverse reinforcement - steel of classes A-1, A -11 and Vr-1 with a diameter of 5 ... 8 mm. Connecting elements, embedded parts and steel clips should be made from rolled sheet steel, shaped profiles, and strip steel.
The calculation of stone and reinforced masonry structures is carried out according to the limit state method. In this case, 2 groups of limit states are taken into account: the first in terms of bearing capacity (strength and stability), the second - in the formation and opening of cracks (masonry seams) and deformations. The calculation for the first group is always performed for all types of structures. The calculation for the second group is carried out for structures where cracks are not allowed (tank linings) or their incomplete opening is required (eccentrically compressed elements with large eccentricities), deformations are limited under the conditions of joint operation of adjacent structures (wall fillings of building frames), etc. The purpose of the calculation is selecting sections of elements or checking existing sections. The calculated stresses, strains and crack widths must not exceed the limit values established by the standards.
The calculation for the bearing capacity is made from the condition that the design force N is less than or equal to the design bearing capacity. The design force is calculated under the action of loads taken with a safety factor in case of their unfavorable combination. The design bearing capacity is determined depending on the geometric dimensions of the section, the design resistance of the masonry R and the coefficients of the working conditions. The design resistance, taking into account the possibility of strength reduction associated with the natural spread of mechanical properties, is taken into account by the reliability factor and is determined by the formula
SNiP II-22-81
BUILDING REGULATIONS
STONE AND REINFORCED STONE STRUCTURES
Introduction date 1983-01-01
DEVELOPED by the Central Research Institute of Building Structures (TsNIISK) them. V.A. Kucherenko Gosstroy of the USSR.
INTRODUCED TsNIISK them. Kucherenko Gosstroy of the USSR
APPROVED by the Decree of the USSR State Committee for Construction of December 31, 1981 No. 292
With the entry into force of this chapter of SNiP, chapter SNiP II-B.2-71 "Masonry and reinforced masonry structures. Design standards" is canceled.
Changes have been made to SNiP II-22-81 "Stone and reinforced masonry structures", approved by the Decree of the USSR Gosstroy of September 11, 1985 N 143 and put into effect on January 1, 1986. Items, tables, which have been amended, are noted in these Building codes sign (K).
Changes were made by the legal bureau "Kodeks" according to the official publication (Ministry of Construction of Russia - SE TsPP, 1995).
1. GENERAL PROVISIONS
1.1. The norms of this chapter must be observed when designing stone and reinforced masonry structures of new and reconstructed buildings and structures.
1.2. When designing stone and reinforced masonry structures, design solutions, products and materials should be used:
a) external walls made of: hollow ceramic and concrete stones and bricks; lightweight brickwork with slab insulation or backfill of porous aggregates; solid stones and concrete blocks on porous aggregates, porous and cellular concrete. The use of solid masonry of solid clay or silicate bricks for the outer walls of rooms with dry and normal humidity conditions is allowed only if it is necessary to ensure their strength;
b) walls made of panels and large blocks made of various types of concrete, as well as bricks or stones;
c) bricks and stones of compressive strength grades of 150 or more in buildings with a height of more than five floors;
d) local natural stone materials;
e) solutions with antifreeze chemical additives for winter masonry, taking into account the instructions of Sec. 7.
Note. With appropriate justification, it is allowed to apply design solutions, products and materials that are not provided for in this paragraph.
1.3. Application of silicate bricks, stones and blocks; stones and blocks from cellular concrete; hollow bricks and ceramic stones; clay brick semi-dry pressing is allowed for the outer walls of premises with a wet regime, provided that a vapor barrier coating is applied to their inner surfaces. The use of these materials for the walls of rooms with a wet regime, as well as for the outer walls of basements and plinths, is not allowed. The humidity regime of the premises should be taken in accordance with the chapter of SNiP on building heat engineering.
1.4. The strength and stability of structures and their elements must be ensured during construction and operation, as well as during transportation and installation of prefabricated structures.
1.5. When calculating structures, one should take into account the reliability factors, taken in accordance with the Rules for Accounting for the Degree of Responsibility of Buildings and Structures in the Design of Structures, approved by the USSR State Construction Committee.
1.6. When designing buildings and structures, measures should be taken to ensure the possibility of their construction in winter conditions.
2. MATERIALS
2.1(K). Brick, stones and mortars for stone and reinforced masonry structures, as well as concrete for the manufacture of stones and large blocks must meet the requirements of the relevant GOSTs and apply the following grades or classes:
a) stones - in terms of compressive strength (and brick - in compression, taking into account its bending strength): 4, 7, 10, 15, 25, 35, 50 (low-strength stones - light concrete and natural stones); 75, 100, 125, 150, 200 (medium strength - brick, ceramic, concrete and natural stones); 250, 300, 400, 500, 600, 800, 1000 (high strength - brick, natural and concrete stones);
b) (K) concretes of compressive strength classes:
heavy - B3.5; AT 5; B7.5; B12.5; B15; IN 20; B25; B30;
on porous aggregates - B2; B2.5; B3.5; AT 5; B7.5; B12.5; B15; IN 20; B25; B30;
cellular - B1; IN 2; B2.5; B3.5; AT 5; B7.5; B12.5;
macroporous - B1; IN 2; B2.5; B3.5; AT 5; B7.5;
porous - B2.5; B3.5; AT 5; B7.5;
silicate - B12.5; B15; IN 20; B25; B30.
It is allowed to use concretes as heat insulators, the compressive strengths of which are 0.7 MPa (7 kgf/) and 1.0 MPa (10 kgf/); and for liners and plates not less than 1.0 MPa (10 kgf/);
c) solutions in terms of compressive strength - 4, 10, 25, 50, 75, 100, 150, 200;
d) stone materials for frost resistance - Mrz 10, Mrz 15, Mrz 25, Mrz 35, Mrz 50, Mrz 75, Mrz 100, Mrz 150, Mrz 200, Mrz 300.
For concrete, the frost resistance grades are the same, except for Mrz 10.
2.2. Solutions with a density in the dry state - 1500 kg / and more - heavy, up to 1500 kg / - light.
2.3. Design grades for frost resistance of stone materials for the outer part of the walls (for a thickness of 12 cm) and for foundations (for the entire thickness) erected in all building and climatic zones, depending on the expected service life of structures, but not less than 100, 50 and 25 years , are given in table. 1 and pp. 2.4 and 2.5.
Note. Design marks for frost resistance are set only for materials from which the upper part of the foundations is being built (up to half of the estimated depth of soil freezing, determined in accordance with the chapter of SNiP "Foundations of buildings and structures").
Table 1
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Type of structures |
Values of MPS for the expected service life of structures, years |
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1. External walls or their cladding in buildings with indoor humidity conditions: |
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a) dry and normal |
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b) wet |
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c) wet |
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2. Foundations and underground parts of walls: |
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a) from bricks of clay plastic pressing |
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b) from natural stone |
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Notes: 1. Marks for frost resistance of stones, blocks and panels made from concrete of all types should be taken in accordance with the chapter of SNiP on the design of concrete and reinforced concrete structures. 2. Brands for frost resistance, given in table. 1, for all building and climatic zones, except for those specified in clause 2.5 of these standards, can be reduced for masonry of clay bricks of plastic pressing by one step, but not lower than Mrz 10 in the following cases: a) for the outer walls of rooms with dry and normal humidity conditions (pos. 1, a), protected from the outside by facings with a thickness of at least 35 mm that meet the frost resistance requirements given in Table. 1, frost resistance of facing bricks and ceramic stone must be at least Mrz 25 for all service life of structures; b) for external walls with damp and wet conditions of premises (pos. 1, b and 1, c), protected from the inside by waterproofing or vapor barrier coatings; c) for foundations and underground parts of the walls of buildings with sidewalks or blind areas, erected in low-moisture soils, if the groundwater level is 3 m or more below the planned ground elevation (pos. 2). 3. Brands for frost resistance, given in pos. 1 for facings with a thickness of less than 35 mm, increase by one step, but not higher than Mrz 50, and facings of buildings erected in the Northern building-climatic zone - by two steps, but not higher than Mrz 100. 4. Marks for frost resistance of stone materials, given in pos. 2, applied to foundations and underground parts of walls, should be increased by one step if the groundwater level is less than 1 m below the planning ground level. 5. Grades of stone for frost resistance for laying open structures, as well as structures of structures erected in the zone of variable groundwater level (retaining walls, reservoirs, weirs, side stones, etc.), are accepted according to regulatory documents approved or agreed by the USSR State Construction Committee . 6. In agreement with the state construction agencies of the Union Republics, the requirements for frost resistance tests are not applied to natural stone materials, which, based on the experience of past construction, have shown sufficient frost resistance in similar operating conditions. |
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2.4. For construction areas located to the east and south of the cities: Grozny, Volgograd, Saratov, Kuibyshev, Orsk, Karaganda, Semipalatinsk, Ust-Kamenogorsk, the requirements for frost resistance of materials and products used for the structures specified in Table. 1, it is allowed to reduce by one step, but not lower than Mrz 10.
Note. The values of the steps correspond to the values given in clause 2.1, d.
2.5. For the Northern building-climatic zone, as well as for the coasts of the Arctic and Pacific Oceans 100 km wide, not included in the Northern building-climatic zone, frost resistance grades of materials for the outer part of the walls (with solid walls - for a thickness of 25 cm) and for foundations ( over the entire width and height) should be one step higher than those indicated in Table. 1, but not higher than Mrz 50 for ceramic and silicate materials, as well as natural stones.
Note. Definitions of the boundaries of the Northern building-climatic zone and its subzones are given in the chapter of SNiP on building climatology and geophysics.
2.6. For reinforcement of stone structures in accordance with the chapter of SNiP on the design of concrete and reinforced concrete structures, the following should be used:
for mesh reinforcement - reinforcement of classes A-I and Bp-I;
for longitudinal and transverse reinforcement, anchors and ties - reinforcement of classes A-I, A-II and Bp-I (taking into account the instructions of P.3.19).
For embedded parts and connecting plates, steel should be used in accordance with the SNiP chapter on the design of steel structures.
3. CALCULATED CHARACTERISTICS
Design resistances
3.1. The calculated resistance to compression of masonry made of bricks of all types and ceramic stones with slit-like vertical voids up to 12 mm wide with a masonry row height of 50–150 mm in heavy mortars are given in Table. 2.
table 2
|
Brand of brick or stone |
Design resistances MPa (kgf /), compression of masonry of all types of bricks and ceramic stones with slit-like vertical voids up to 12 mm wide at a masonry row height of 50 - 150 mm on heavy mortars |
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with brand of solution |
at solution strength |
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Note. The design resistance of masonry on mortar grades from 4 to 50 should be reduced by applying reduction factors: 0.85 - for masonry on hard cement mortars (without lime or clay additives), light and lime mortars up to 3 months old; 0.9 - for laying on cement mortars (without lime or clay) with organic plasticizers. It is not required to reduce the design compressive strength for masonry of the highest quality - the mortar joint is made under the frame with alignment and compaction of the mortar with a lath. The project indicates the brand of mortar for ordinary masonry and for high quality masonry. |
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3.2. The calculated resistance to compression of vibro-brick masonry on heavy mortars are given in Table. 3.
Table 3
|
Brick brand |
Design resistances MPa (kgf/), compression of vibrobrick masonry on heavy solutions at brand of solution |
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Notes: 1. Calculated compressive strengths of brickwork vibrated on vibrating tables are taken according to Table. 3 with a coefficient of 1.05. 2. Calculated compressive strengths of vibro-brickwork with a thickness of more than 30 cm should be taken from Table. 3 with a coefficient of 0.85. 3. Estimated resistance given in table. 3 refer to masonry sections with a width of 40 cm or more. In self-supporting and non-bearing walls, sections with a width of 25 to 38 cm are allowed, while the design resistance of the masonry should be taken with a coefficient of 0.8. |
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3.3. The calculated compressive strength of masonry from large concrete solid blocks of all types of concrete and from blocks of natural stone (sawn or pure tesky) with a masonry row height of 500 - 1000 mm are given in Table. 4.
Table 4(K)
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Design resistances MPa (kgf/), compression masonry of large solid blocks of all types of concrete and blocks of natural stone (sawn or pure tesque) with a height of a row of masonry 500 - 1000 mm |
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with brand of solution |
at zero strength |
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solution |
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1000 800 600 500 400 300 250 200 150 100 |
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Notes: 1. Calculated compressive strength of masonry from large blocks with a height of more than 1000 mm are taken according to Table. 4 with a factor of 1.1. 2. Classes of concrete should be taken according to Table 1 ST SEV 1406-78. For the brand of natural stone blocks, one should take the compressive strength MPa (kgf /), a reference cube sample tested in accordance with the requirements of GOST 10180 - 78 and GOST 8462 - 75. 3. The design resistance to compression of masonry from large concrete blocks and natural stone blocks, mortar joints in which are made under the frame with leveling and compaction with a rail (as indicated in the project), can be taken according to Table. 4 with a factor of 1.2. |
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3.4. The calculated compressive strength of masonry made of solid concrete stones and natural stones (sawn or pure tesky) are given in Table. 5.
Table 5
|
Stone brand |
Design resistances MPa (kgf /), compression of masonry from solid concrete, gypsum concrete and natural stones (sawn or pure tesky) with a height of a row of masonry 200 - 300 mm |
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with brand of solution |
With the strength of the solution |
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Notes: 1. The design resistance of masonry from solid cinder-concrete stones made using slag from the combustion of brown and mixed coals should be taken from Table. 5 with a coefficient of 0.8. 2. Gypsum concrete stones may only be used for laying walls with a service life of 25 years (see clause 2.3); in this case, the calculated resistance of this masonry should be taken from Table. 5 with coefficients: 0.7 for laying external walls in areas with a dry climate, 0.5 - in other areas; 0.8 - for internal walls. Climatic zones are accepted in accordance with the head of SNiP on building heat engineering. 3. The design resistance of masonry made of concrete and natural stones of grade 150 and higher with even surfaces and dimensional tolerances not exceeding ± 2 mm, with a mortar joint thickness of not more than 5 mm, made on cement pastes or adhesive compositions, it is allowed to take according to Table. 5 with a coefficient of 1.3. |
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3.5. The calculated resistance to compression of masonry from hollow concrete stones with a row height of 200 - 300 mm are given in Table. 6.
Table 6
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Design resistances MPa (kgf /), compression of masonry from hollow concrete stones with a height of a row of masonry 200 - 300 mm |
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with brand of solution |
at solution strength |
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Note. The calculated compressive strength of masonry from hollow cinder-concrete stones made using slag from the combustion of brown and mixed coals, as well as masonry from gypsum-concrete, hollow stones, should be reduced in accordance with notes 1 and 2 to table. 5. |
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3.6. Calculated compressive strengths of masonry made of natural stones (sawn and pure tesky) with a row height of up to 150 mm are given in Table. 7.
With brand of solution
at solution strength
1. From natural stones with a row height of up to 150 mm
2. The same, with a row height of 200 - 300 mm
3.7. The calculated resistance to compression of rubble masonry from torn rubble are given in table. eight.
zero
Notes: 1. Given in Table. 8 design resistances for rubble masonry are given at the age of 3 months. for grades of solution 4 and more. In this case, the brand of the solution is determined at the age of 28 days. For laying at the age of 28 days. design resistance given in table. 8, for solutions of brand 4 and more should be taken with a factor of 0.8.
2. For laying of bedded rubble stone, the calculated resistances adopted in Table. 8 should be multiplied by a factor of 1.5.
3. The design resistance of the rubble masonry of foundations covered with soil on all sides is allowed to be increased: when laying, followed by backfilling the sinuses of the pit with soil - by 0.1 MPa (1 kgf /; when laying in "spread" trenches with untouched soil and with superstructures - by 0.2 MPa (2 kgf /).
Foreword
The goals and principles of standardization in the Russian Federation are established by the Federal
Law of December 27, 2002 No. 184-FZ "On Technical Regulation", and the development rules -
Decree of the Government of the Russian Federation dated November 19, 2008 No. 858 “On the procedure for
development and approval of codes of practice”.
About the set of rules
1 PERFORMERS - Central Research Institute of Building
designs to them. V.A. Kucherenko (TsNIISK named after V.A. Kucherenko) Institute of JSC "National Research
"Construction"
2 INTRODUCED by the Technical Committee for Standardization TC 465 "Construction"
3 PREPARED for approval by the Department of Architecture, Construction and
urban policy
4 APPROVED by the Order of the Ministry of Regional Development of the Russian Federation
(Ministry of Regional Development of Russia) dated December 29, 2011 No. 635/5 and entered into force on January 01, 2013.
5 REGISTERED by the Federal Agency for Technical Regulation and
metrology (Rosstandart). Revision of SP 15.13330.2010 "SNiP II-22-81* Stone and reinforced stone
structures"
Information about changes to this set of rules is published annually.
published information index "National Standards", and the text of the amendments and
amendments - in the monthly published information indexes "National Standards".
In case of revision (replacement) or cancellation of this set of rules, the relevant
notice will be published in a monthly information index
"National Standards". Relevant information, notification and texts
are also placed in the public information system - on the official website
developer (Ministry of Regional Development of Russia) on the Internet.
1 area of use............................................... ................................................. ...........one
2 Normative references ............................................................... ................................................. ...........one
3 Terms and definitions .......................................................... ................................................. .......one
4 General provisions.................................................... ................................................. ..............one
5 Materials .................................................. ................................................. .........................2
6 Rated characteristics............................................................... ................................................. ..4
7 Calculation of structural elements according to the limit states of the first group (according to
bearing capacity) ............................................................... ................................................. .........eighteen
8 Calculation of structural elements according to the limit states of the second group (according to
formation and opening of cracks and deformations). .................35
9 Structural design ............................................................... ...............................................37
10 Guidelines for the design of structures erected in winter ..............................................................62
Annex A (mandatory) List of regulatory documents .................................................................. .66
Annex B (mandatory) Terms and definitions .......................................... .................67
Annex B (normative) Basic letter designations of quantities ..........................................................68
Annex D (recommended) Calculation of the walls of buildings with a rigid structural
scheme ................................................. ................................................. ...............................73
Annex D (recommended) Requirements for reinforcement of masonry front
layer................................................. ................................................. .................................76
Annex E (recommended) Calculation of walls of multi-storey buildings made of stone
masonry to the vertical load on the opening of cracks at
different loading or different rigidity of adjacent sections
walls ................................................. ................................................. .................................79
Bibliography................................................. ................................................. .................81
Introduction
This set of rules has been drawn up taking into account the requirements of federal
laws of December 27, 2002 No. 184-FZ "On technical regulation", dated
June 22, 2008 No. 123-FZ "Technical regulations on the requirements
fire safety", dated December 30, 2009 No. 384-FZ "Technical
regulation on the safety of buildings and structures.
The update was carried out by the team of authors of the TsNIISK im.
V.A. Kucherenko - Institute of JSC "NIC "Construction":
tech candidates. Sciences A.V. Granovsky, M.K. Ishchuk (heads
works), V.M. Bobryashov, N.N. Kruchinin, M.O. Pavlova, S.I. Chigrin;
engineers: A.M. Gorbunov, V.A. Zakharov, S.A. Minakov, A.A. Frolov
(TsNIISK named after V.A. Kucherenko); tech candidates. Sciences A.I. Bedov (MGSU),
A.L. Altukhov (MOSGRAZHDANPROEKT). General edition - Cand. tech. Sciences O.I. Ponomarev (TsNIISK named after V.A. Kucherenko).
SET OF RULES
STONE AND REINFORCED STONE STRUCTURES
Masonry and reinforced masonry structures
Introduction date 2013-01-01
1 area of use
This set of rules applies to the design of masonry and
reinforced masonry structures of new and reconstructed buildings and structures
for various purposes, operated in the climatic conditions of Russia.
The standards establish requirements for the design of stone and reinforced masonry
structures built using ceramic and silicate bricks,
ceramic, silicate, concrete blocks and natural stones.
The requirements of these standards do not apply to the design of buildings and
structures subject to dynamic loads, erected on
undermined territories, permafrost soils, in seismically hazardous areas, and
also bridges, pipes and tunnels, hydraulic structures, thermal units.
2 Normative references
Normative documents, to which there are references in the text of these norms,
are given in Appendix A.
Note - When using this set of rules, it is advisable to check
the effect of reference standards and classifiers in the public information system on
official website of the national body of the Russian Federation for standardization on the Internet
or according to the annually published information index "National Standards", which
published as of January 1 of the current year, and according to the corresponding monthly published
information signs published in the current year. If the referenced document is replaced
(changed), then when using this set of rules, you should be guided by the replaced
(modified) document. If the referenced document is canceled without replacement, then the provision in which
a link to it is given, applies to the part that does not affect this link.
3 Terms and definitions
This set of rules adopts the terms and definitions given in Appendix B.
4 General provisions
4.1 When designing masonry and reinforced masonry structures,
apply constructive solutions, products and materials that provide
required bearing capacity, durability, fire safety,
thermal characteristics of structures and temperature and humidity conditions
(GOST 4.206, GOST 4.210, GOST 4.219).
4.2 When designing buildings and structures, it is necessary to provide
measures to ensure the possibility of their construction in winter conditions.
4.3 Application of silicate bricks, stones and blocks; stones and blocks
cellular concrete; hollow ceramic bricks and stones, concrete blocks with
voids; ceramic brick semi-dry pressing is allowed for outdoor
walls of premises with a wet regime, subject to application to their internal
vapor barrier surface. The use of these materials for
walls of rooms with a wet regime, as well as for the outer walls of basements, plinths and
foundations are not allowed.
The use of three-layer masonry with effective insulation for external walls
rooms with a wet operating mode is allowed provided that it is applied to
their inner surfaces of the vapor barrier coating. The use of such masonry
for external walls of rooms with a wet mode of operation, as well as for
the outer walls of basements are not allowed.
4.4 The design of building elements should not be
the cause of the latent spread of combustion throughout the building, structure, structure.
When used as an inner layer of combustible insulation, the limit
fire resistance and constructive fire hazard class of building structures
must be determined under the conditions of standard fire tests or by a calculation and analytical method.
Techniques for conducting fire tests and calculation and analytical methods
determination of fire resistance limits and constructive fire hazard class
building structures are established by regulatory documents on fire
security.
4.5 The application of this document ensures that the requirements are met
Technical regulation "On the safety of buildings and structures".