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Engineering Construction Standard Full Text Information System
National Standard of the People's Republic of China
Wood Structure Design Code
GBJ5-88
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National Standard of the People's Republic of China
Wood Structure Design Code
GBJ5—88
Editor Department: Former Ministry of Urban and Rural Construction and Environmental Protection of the People's Republic of China Approval Department: Ministry of Construction of the People's Republic of China Implementation Date: 1989
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Notice on the Release of the National Standard "Wood Structure Design Code"
(88) Jianbiaozi No. 272
According to the requirements of the former National Construction Committee (81) Jianfashezi No. 546, the "Wood Structure Design Code" revised by China Construction Southwest Design Institute, Sichuan Provincial Academy of Architectural Sciences and Harbin Institute of Architecture and Civil Engineering and other relevant units has been reviewed by relevant departments. The revised "Wood Structure Design Code" GBJ5-88 is now approved as a national standard and will be implemented on July 1, 1989. The original "Wood Structure Design Code" GBJ5-73 will be abolished on January 1, 1991.
This code is managed by the Ministry of Construction, and the specific interpretation work is the responsibility of China Construction Southwest Design Institute. The publication and distribution is the responsibility of China Architecture Industry Press. Ministry of Construction of the People's Republic of China
October 14, 1988
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Revision Notes
This code is based on the requirements of the former State Construction Commission (81) Jianfa Shezi No. 546, and is revised by China Construction Southwest Design Institute, Sichuan Academy of Architectural Sciences and Harbin Institute of Architecture and Architecture in conjunction with relevant domestic scientific research, design, construction units and colleges and universities to "Wood Structure Design Code" (GBJ5-73). During the revision process of this code, the revision group organized relevant design, scientific research and colleges and universities across the country to conduct a large number of investigations, studies and scientific experiments according to the unified plan requirements, and summarized the domestic engineering practice experience and scientific research results in recent years: referring to relevant international standards and advanced foreign standards, after extensively soliciting opinions from relevant units across the country, after repeated revisions, it was finally reviewed and finalized by our ministry in conjunction with relevant departments. This code is divided into eight chapters and eleven appendices. The main contents of this revision are: according to the provisions of the national standard "Unified Standard for Design of Building Structures" GBJ68-84, adopt the limit state design based on probability theory, fully calibrate the reliability index β value, and improve the material strength classification method; change the stability coefficient of axially compressed members to use two curves; improve the calculation formula of the bearing capacity of compression and bending members, and revise the calculation coefficient of tooth connection, value: add the content of glued technical structure, add the content of technical structure design on construction quality requirements, and improve the anticorrosion and insect repellent of wood structure and add fire prevention measures for wood structure. This code must be used in conjunction with various building structure design standards and specifications such as "Building Structure Load Code" GBJ9-87 formulated and revised according to the "Unified Standard for Design of Building Structures" GBJ68-84 approved and issued by the state in 1984, and shall not be mixed with various national building structure design standards and specifications that have not been formulated and revised according to the "Unified Standard for Design of Building Structures" GBJ68-84.
In order to further improve the revision level of this code, each unit should pay attention to accumulating information and summarizing experience in the process of implementing this code. If there is a need for modification and supplement, please send your opinions and relevant information to China Architecture Southwest Design Institute (Jinhua Street, Chengdu, Sichuan) for reference in future revisions.
Ministry of Construction of the People's Republic of China
July 1988
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Chapter 1 General Provisions
Chapter 2
Section 1
Section 2
Section 3
Chapter 3
Section 1
Section 2
Chapter 4
Structural Adhesives
Basic Design Provisions
Design Principles
Design Indicators and Allowable Values…
Calculation of Timber Structural Members.
Section 1
Section 2
Section 3
Chapter 5
Section 1
Section 2
Chapter 6||t t||Section 1
Section 2
Section 3
Section 4
Section 5
Section 6
Section 7
Chapter 7
Section 1
Section 2
Section 3
Axial tension and axial compression members
Bending members
Tension-bending and compression-bending members
Calculation of wood structure connections
Tooth connections
Bolt connections and nail connections
Design and construction of wood structures
General provisions
Wooden roof base and wooden beams
Glued-laminated timber structures
Quality requirements of design for construction
General provisions
Member production
Production and assembly of structural connections
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Section 4 Transportation and Installation of Wood Structures
Chapter 8 Corrosion and Pest Control and Fire Prevention of Wood Structures Corrosion and Pest Control of Wood Structures
Section 1
Section 2
Appendix—
Appendix 2
Appendix 3
Appendix 4
Appendix 5
Fire prevention of wood structures
Design requirements for the use of newly utilized wood species in load-bearing structures Material standards for load-bearing structural wood
Inspection and maintenance requirements for wood structures
Test standards for adhesive ability
Names of wood used in this code and main characteristics of wood of common tree species
Stability coefficient of axially compressed members
Appendix 6
Appendix 7 Test standards for wood strength
Appendix 8 Requirements for gluing process
Appendix 9 Requirements for wood antiseptic and anti-insect treatment
Appendix 10 Conversion relationship between non-legal measurement units and legal measurement units 66 Appendix 11 Explanation of terms used in this specification
Additional explanation·
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Main symbols
Effects
-Design value of bending moment;
-Design value of axial force;
Ns——Design value of tension borne by the safety bolt;-Design value of shear force;
-Design value of axial tensile stress,
Design value of axial compressive stress;
Design value of bending stress;
Design value of shear stress;
の—Deflection of bending member.
Material properties and resistance
E——Elastic modulus of wood along the grain;
f. Design value of tensile strength of wood along the grain;
f. —Design value of compressive and bearing strength of wood along the grain; fe,90——Design value of wood transverse compression strength, f. —Design value of wood diagonal compression strength; fm—Design value of wood bending strength;
f. —Design value of wood parallel shear strength; N. —Design bearing capacity of each shear surface of a connection; []——Allowable deflection value of a bending member. What parameters
A——Gross cross-sectional area,
A——Net cross-sectional area;
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A—Calculation area of the cross section,
A——Bearing surface area,
A——Shear surface area,
I——Gross section moment of inertia;
S——Gross section area moment; ||tt ||W——gross section resistance moment,
——net section resistance moment;
——section width;
b——shear width;
——diameter;
h——section height,
i——radius of gyration;
1——length or span;
calculated length of compression member;
-shear length;
r——radius,
T. ——radius of curvature of arc-shaped member;
8——spacing of bolts, nails, etc.;
thickness of steel plate and lamina;
——angle,
——slope;
in——slenderness ratio;
calculation coefficient
9——stability coefficient of axially compressed member;
——calculation coefficient of design bearing capacity of bolt or nail connection;. —Reduction coefficient for considering the diagonal bearing of wood in bolted connection; —Reduction coefficient for considering the uneven distribution of shear stress along the length of the shear plane; m
-Correction coefficient for the bending strength of curved wood members. Engineering Construction Standard Full-text Information System
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Chapter I General Provisions
Article 1.0.1 This specification is specially formulated to implement the national technical and economic policies in the design of wood structures, to achieve advanced technology, economic rationality, safety and applicability, ensure quality and save wood.
Article 1.0.2
This specification is applicable to the design of load-bearing wood structures (including load-bearing glued wood structures composed of wooden boards) of industrial and civil houses and general structures. Article 1.0.3 The design principles of this specification are formulated in accordance with the national standard "Uniform Standard for Design of Building Structures" GBJ68-84. Article 1.0.4 Load-bearing wood structures should be used in house structures and structures in normal temperature and humidity environments.
Wooden structures should not be used for houses and structures under the following production and use conditions: 1. Extremely prone to fire;
2. Affected by high production temperatures, the wood surface temperature is higher than 50°C; 3. Frequently damp and difficult to ventilate.
Article 1.0.5 The design of wooden structures shall comply with the provisions of this code and the relevant national standards and specifications in force in addition to complying with the provisions of this code. Engineering Construction Standard Full Text Information System
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Chapter 2 Materials
Section 1 Wood
Article 2.1.1 Wood for load-bearing structures shall be selected from the tree species listed in Table 3.2.1-1 of this code. The main load-bearing components should be made of coniferous wood; important wooden connectors should be made of fine, straight-grained, knot-free and other defect-free hard broad-leaved wood that is resistant to corrosion. On the premise of ensuring the quality of the project, the use of tree species can be gradually expanded. When using newly used wood species for load-bearing structures, the design can be carried out in accordance with the requirements of Appendix 1 of this Code.
Article 2.1.2 The wood used for load-bearing structures can be divided into three grades. When designing, the appropriate grade of wood should be selected according to the requirements of Table 2.1.2-1 based on the type of force of the component.
Material grade of wood components of load-bearing structures
Component categories
Tensile or tension-bending components
Bending or compression-bending components
Compression components and secondary bending components (such as hanging keels, etc.) Table 2.1.2-1
Village quality grade
Note: 1. Secondary components such as roof panels and tile hanging strips can be selected according to local customs, and this Code does not uniformly stipulate their material grades.
2. The material grade of wood in this table is graded according to the force requirements of the load-bearing structure. The material selection should comply with the material standards of Appendix 2 of this Code and shall not be replaced by the grade standards of general commercial materials. The wood material used in glued laminated timber structures is also divided into three grades. When designing, the appropriate grade of wood should be selected according to the type and location of the force on the glued laminated timber components and the requirements of Table 2.1.2-2.
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Material Grade Table of Glued Laminated Timber Components
Component Category
Tension or Tension-Bending Components
Compression Components (excluding the upper chords of arches and trusses)
The upper chords of arches or trusses and glued laminated beams with a height of no more than 500mm
(1) The upper and lower edges of the components are 15 areas, and there are no less than two layers of boards
(2) The rest| |tt||Glued laminated beams with a height greater than 500 mm
(1) 0.15 area of the tension edge of the beam,
and not less than two layers of plates
(2) 0.15 to
from the production edge of the beam (3) 0.15 area of the compression edge of the beam,
and not less than two layers of plates
(4) The rest
Side web I-beam
(1) Tension flange plate
(2) Compression flange plate
(3) Web plate
Note: 1. h——Section height.
2. Same as Note 2 of Table 2.1.2-1.
Table 2.1.2-2
Wood grade configuration diagram
The material standards of each grade of wood selected shall comply with the provisions of Appendix II of this Code. Article 2.1.3 When making components, the moisture content of wood shall meet the following requirements: 1. For log or square timber structures, it shall not be greater than 25%; 2. For plate structures and connecting plates of tension members, it shall not be greater than 18%; Engineering Construction Standard Full Text Information System
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3. For wooden connectors, it shall not be greater than 15%; 4. For glued wood structures, it shall not be greater than 15%, and the difference in moisture content between the boards of the same component shall not be greater than 5%.
Article 2.1.4 When conditions limit the use of wet wood to make log or square timber structures directly, the following provisions shall be met:
1. The lower chord of the truss should be made of steel or round steel. When using wooden lower chords, logs or square timber with "broken core" (Figure 2.1.4) should be used. 2. The tension web of the truss should be made of round steel for easy adjustment. 3. The calculation and construction shall comply with the provisions of this code on wet materials. 4. Wet materials should not be used to make connecting plates of plate structures and tension members. 5. After the construction of a house or structure, the inspection and maintenance of the structure should be strengthened. The inspection and maintenance of the structure can be carried out in accordance with the provisions of Appendix III of this code. a)
Figure 2.1.4 "Broken-hearth" square timber
Section 2 Steel
Article 2.2.1 The steel used in load-bearing wooden structures should be No. 3 open-hearth or oxygen converter steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel". For structures that bear vibration loads or have a calculated temperature below -30°C, No. 3 killed steel should be used.
Article 2.2.2 The bolt material should be No. 3 steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel".
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WArticle 4 Load-bearing wood structures should be used in house structures and structures in normal temperature and humidity environments.
Houses and structures under the following production and use conditions should not use wood structures: 1. Extremely prone to fire;
2. Affected by high production temperatures, the wood surface temperature is higher than 50°C; 3. Frequently damp and difficult to ventilate.
Article 1.0.5 In addition to complying with the provisions of this code, the design of wood structures shall also comply with the provisions of the current relevant national standards and specifications. Engineering Construction Standard Full Text Information System
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Engineering Construction Standard Full Text Information System
Chapter 2 Materials
Section 1 Wood
Article 2.1.1 Wood used for load-bearing structures shall be selected from the tree species listed in Table 3.2.1-1 of this code. The main load-bearing components should be made of coniferous wood; important wooden connectors should be made of hard broad-leaved wood that is fine, straight-grained, knot-free and free of other defects and is resistant to corrosion. On the premise of ensuring the quality of the project, the use of tree species can be gradually expanded. When using newly used tree species for load-bearing structures, the design can be carried out in accordance with the requirements of Appendix 1 of this code.
Article 2.1.2 The material of wood used for load-bearing structures can be divided into three grades. When designing, the appropriate grade of wood should be selected according to the requirements of Table 2.1.2-1 based on the type of force on the component.
Material Grade of Wood Components of Load-bearing Structures
Component Category
Tensile or Tension-bending Components
Bending or Compression-bending Components
Compression Components and Secondary Bending Components (such as Hanging Neck Small Keels, etc.) Table 2.1.2-1
Material Grade of Wood Components
Note: 1. Secondary components such as roof panels and tile hanging strips can be selected according to local practices. This specification does not uniformly specify their material grades.
2. The material grades of wood in this table are graded according to the load requirements of the load-bearing structure. The material selection should comply with the material standards in Appendix 2 of this specification and shall not be replaced by the grade standards of general commercial materials. The wood materials used in glued wood structures are also divided into three grades. When designing, the appropriate grade of wood should be selected according to the type and location of the load of glued wood components and the requirements of Table 2.1.2-2.
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Material Grade Table of Glued Laminated Timber Components
Component Category
Tension or Tension-Bending Components
Compression Components (excluding the upper chord of arches and trusses)
The upper chord of arches or trusses and glued laminated beams with a height of no more than 500mm
(1) The upper and lower edges of the components are 15 in the area, and there are no less than two layers of boards
(2) The rest| |tt||Glued laminated beams with a height greater than 500 mm
(1) 0.15 area of the tension edge of the beam,
and not less than two layers of plates
(2) 0.15 to
from the production edge of the beam (3) 0.15 area of the compression edge of the beam,
and not less than two layers of plates
(4) The rest
Side web I-beam
(1) Tension flange plate
(2) Compression flange plate
(3) Web plate
Note: 1. h——Section height.
2. Same as Note 2 of Table 2.1.2-1.
Table 2.1.2-2
Wood grade configuration diagram
The material standards of each grade of wood selected shall comply with the provisions of Appendix II of this Code. Article 2.1.3 When making components, the moisture content of wood shall meet the following requirements: 1. For log or square timber structures, it shall not be greater than 25%; 2. For plate structures and connecting plates of tension members, it shall not be greater than 18%; Engineering Construction Standard Full Text Information System
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3. For wooden connectors, it shall not be greater than 15%; 4. For glued wood structures, it shall not be greater than 15%, and the difference in moisture content between the boards of the same component shall not be greater than 5%.
Article 2.1.4 When conditions limit the use of wet wood to make log or square timber structures directly, the following provisions shall be met:
1. The lower chord of the truss should be made of steel or round steel. When using wooden lower chords, logs or square timber with "broken core" (Figure 2.1.4) should be used. 2. The tension web of the truss should be made of round steel for easy adjustment. 3. The calculation and construction shall comply with the provisions of this code on wet materials. 4. Wet materials should not be used to make connecting plates of plate structures and tension members. 5. After the construction of a house or structure, the inspection and maintenance of the structure should be strengthened. The inspection and maintenance of the structure can be carried out in accordance with the provisions of Appendix III of this code. a)
Figure 2.1.4 "Broken-hearth" square timber
Section 2 Steel
Article 2.2.1 The steel used in load-bearing wooden structures should be No. 3 open-hearth or oxygen converter steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel". For structures that bear vibration loads or have a calculated temperature below -30°C, No. 3 killed steel should be used.
Article 2.2.2 The bolt material should be No. 3 steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel".
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WArticle 4 Load-bearing wood structures should be used in house structures and structures in normal temperature and humidity environments.
Houses and structures under the following production and use conditions should not use wood structures: 1. Extremely prone to fire;
2. Affected by high production temperatures, the wood surface temperature is higher than 50°C; 3. Frequently damp and difficult to ventilate.
Article 1.0.5 In addition to complying with the provisions of this code, the design of wood structures shall also comply with the provisions of the current relevant national standards and specifications. Engineering Construction Standard Full Text Information System
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Engineering Construction Standard Full Text Information System
Chapter 2 Materials
Section 1 Wood
Article 2.1.1 Wood used for load-bearing structures shall be selected from the tree species listed in Table 3.2.1-1 of this code. The main load-bearing components should be made of coniferous wood; important wooden connectors should be made of hard broad-leaved wood that is fine, straight-grained, knot-free and free of other defects and is resistant to corrosion. On the premise of ensuring the quality of the project, the use of tree species can be gradually expanded. When using newly used tree species for load-bearing structures, the design can be carried out in accordance with the requirements of Appendix 1 of this code.
Article 2.1.2 The material of wood used for load-bearing structures can be divided into three grades. When designing, the appropriate grade of wood should be selected according to the requirements of Table 2.1.2-1 based on the type of force on the component.
Material Grade of Wood Components of Load-bearing Structures
Component Category
Tensile or Tension-bending Components
Bending or Compression-bending Components
Compression Components and Secondary Bending Components (such as Hanging Neck Small Keels, etc.) Table 2.1.2-1
Material Grade of Wood Components
Note: 1. Secondary components such as roof panels and tile hanging strips can be selected according to local practices. This specification does not uniformly specify their material grades.
2. The material grades of wood in this table are graded according to the load requirements of the load-bearing structure. The material selection should comply with the material standards in Appendix 2 of this specification and shall not be replaced by the grade standards of general commercial materials. The wood materials used in glued wood structures are also divided into three grades. When designing, the appropriate grade of wood should be selected according to the type and location of the load of glued wood components and the requirements of Table 2.1.2-2.
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Material Grade Table of Glued Laminated Timber Components
Component Category
Tension or Tension-Bending Components
Compression Components (excluding the upper chord of arches and trusses)
The upper chord of arches or trusses and glued laminated beams with a height of no more than 500mm
(1) The upper and lower edges of the components are 15 in the area, and there are no less than two layers of boards
(2) The rest| |tt||Glued laminated beams with a height greater than 500 mm
(1) 0.15 area of the tension edge of the beam,
and not less than two layers of plates
(2) 0.15 to
from the production edge of the beam (3) 0.15 area of the compression edge of the beam,bZxz.net
and not less than two layers of plates
(4) The rest
Side web I-beam
(1) Tension flange plate
(2) Compression flange plate
(3) Web plate
Note: 1. h——Section height.
2. Same as Note 2 of Table 2.1.2-1.
Table 2.1.2-2
Wood grade configuration diagram
The material standards of each grade of wood selected shall comply with the provisions of Appendix II of this Code. Article 2.1.3 When making components, the moisture content of wood shall meet the following requirements: 1. For log or square timber structures, it shall not be greater than 25%; 2. For plate structures and connecting plates of tension members, it shall not be greater than 18%; Engineering Construction Standard Full Text Information System
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3. For wooden connectors, it shall not be greater than 15%; 4. For glued wood structures, it shall not be greater than 15%, and the difference in moisture content between the boards of the same component shall not be greater than 5%.
Article 2.1.4 When conditions limit the use of wet wood to make log or square timber structures directly, the following provisions shall be met:
1. The lower chord of the truss should be made of steel or round steel. When using wooden lower chords, logs or square timber with "broken core" (Figure 2.1.4) should be used. 2. The tension web of the truss should be made of round steel for easy adjustment. 3. The calculation and construction shall comply with the provisions of this code on wet materials. 4. Wet materials should not be used to make connecting plates of plate structures and tension members. 5. After the construction of a house or structure, the inspection and maintenance of the structure should be strengthened. The inspection and maintenance of the structure can be carried out in accordance with the provisions of Appendix III of this code. a)
Figure 2.1.4 "Broken-hearth" square timber
Section 2 Steel
Article 2.2.1 The steel used in load-bearing wooden structures should be No. 3 open-hearth or oxygen converter steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel". For structures that bear vibration loads or have a calculated temperature below -30°C, No. 3 killed steel should be used.
Article 2.2.2 The bolt material should be No. 3 steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel".
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3. For wooden connectors, it should not be greater than 15%. 4. For glued wood structures, it should not be greater than 15%, and the moisture content difference between the boards of the same component should not be greater than 5%.
Article 2.1.4 When conditions limit the use of wet materials to make logs or square timber structures, the following provisions shall be met:
1. The lower chord of the truss should be made of steel or round steel. When using wooden lower chords, logs or square timbers with "broken core" (Figure 2.1.4) should be used. 2. The tension web of the truss should be made of round steel for easy adjustment. 3. The calculation and construction should comply with the provisions of this code on wet materials. 4. The connecting plates of plate structures and tension members should not be made of wet materials. 5. After the house or structure is built, the inspection and maintenance of the structure should be strengthened. The inspection and maintenance of the structure can be carried out in accordance with the provisions of Appendix 3 of this code. a)
Figure 2.1.4 "Broken-hearth" square timber
Section 2 Steel
Article 2.2.1 Steel used in load-bearing wood structures should be No. 3 steel from open-hearth or oxygen converter that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel". For structures that are subject to vibration loads or have a calculated temperature below -30°C, No. 3 killed steel should be used.
Article 2.2.2 Bolt materials should be No. 3 steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel".
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3. For wooden connectors, it should not be greater than 15%. 4. For glued wood structures, it should not be greater than 15%, and the moisture content difference between the boards of the same component should not be greater than 5%.
Article 2.1.4 When conditions limit the use of wet materials to make logs or square timber structures, the following provisions shall be met:
1. The lower chord of the truss should be made of steel or round steel. When using wooden lower chords, logs or square timbers with "broken core" (Figure 2.1.4) should be used. 2. The tension web of the truss should be made of round steel for easy adjustment. 3. The calculation and construction should comply with the provisions of this code on wet materials. 4. The connecting plates of plate structures and tension members should not be made of wet materials. 5. After the house or structure is built, the inspection and maintenance of the structure should be strengthened. The inspection and maintenance of the structure can be carried out in accordance with the provisions of Appendix 3 of this code. a)
Figure 2.1.4 "Broken-hearth" square timber
Section 2 Steel
Article 2.2.1 Steel used in load-bearing wood structures should be No. 3 steel from open-hearth or oxygen converter that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel". For structures that are subject to vibration loads or have a calculated temperature below -30°C, No. 3 killed steel should be used.
Article 2.2.2 Bolt materials should be No. 3 steel that meets the current national "Technical Conditions for Ordinary Carbon Structural Steel".
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