Detail of GB/T 51424-2022

Introduction of GB/T 51424-2022

Foreword According to the requirements of the Notice on Printing and Distributing the 2014 Formulation and Revision Plan of Engineering Construction Standards and Specifications (JB (2013) No. 169) issued by the Ministry of Housing and Urban Rural Development, the standard preparation team has prepared this standard after extensive investigation and research, conscientiously summing up practical experience, referring to relevant international and foreign advanced standards, and on the basis of extensive consultation. The main technical contents of this standard are: general rules, terms and symbols, materials, basic provisions, structural form and layout, structural calculation, component calculation and connection structure, glass and its support frame, etc. The Ministry of Housing and Urban Rural Development is responsible for the management of this standard, the Ministry of Agriculture and Rural Affairs is responsible for the daily management, and the Planning and Design Institute of the Ministry of Agriculture and Rural Affairs is responsible for the interpretation of specific technical content. If you have any comments or suggestions during the implementation process, please send them to the Planning, Design and Research Institute of the Ministry of Agriculture and Rural Affairs (address: No. 41, Maizidian Street, Chaoyang District, Beijing 100125). 1 General 1.0.1 This standard is formulated to standardize the structural design of agricultural greenhouses, ensure safety and applicability, advanced technology, economy and rationality, and ensure quality. 1.0.2 This standard is applicable to the main structure design of plastic greenhouse for agricultural planting, solar greenhouse and multi span greenhouse with light steel structure as the main structure and the envelope structure design of glass greenhouse. This standard is not applicable to the structural design of plastic greenhouses and solar greenhouses with non light steel structures such as bamboo, timber, suspension and reinforced concrete structures. 1.0.3 In the greenhouse structure design drawings and design documents, the design service life of the greenhouse, the grade and quality grade of steel and other materials shall be indicated Supply conditions and model or steel grade of connecting materials] If necessary, additional guarantee contents such as mechanical property and chemical composition of steel shall be indicated 1.0.4 The strength and stability of masonry wall shall be calculated according to the current national standard Code for Design of Masonry Structures GB 50003. ") 1.0.57. The foundation design shall be carried out in accordance with the current industry standard Code for Design, Construction and Acceptance of Greenhouse Foundation (NY/T 1145). 1.0.6 In addition to this standard, the structural design of agricultural greenhouse shall also comply with the provisions of the current national standards. 2 Terms and symbols 2.1 Terminology 2.1.1 Greenhouse greenhouse It is a facility that uses light transmitting covering materials as the whole or part of the enclosure structure and has certain environmental control equipment to resist adverse weather conditions and ensure the normal growth and development of crops. It can be divided into plastic greenhouses, solar greenhouses and multi span greenhouses according to the building form. 2.1.2 Plastic shed plastic' tunneh The farming machinery or planting personnel can enter the single arch plastic shed without opening the plastic film or removing the arch frame. 2.1.3 Solar greenhouse It is composed of thermal insulation or thermal storage wall, thermal insulation roof and daylighting roof It is a single roof greenhouse that uses solar energy separately and uses thermal insulation materials to cover the daylighting roof at night for thermal insulation and overwintering crop production. 2.1.4 Multi span greenhouse gutter connected greenhouse Greenhouse with two or more spans connected by gutter. 2.2 Symbols 3 Materials 3.1 Concrete and masonry materials 3.1.1 Concrete materials shall comply with the provisions of the current national standard Code for Design of Concrete Structures (GB 50010). 3.1.2 Masonry materials shall comply with the current national standard Code for Design of Masonry Structures (GB50003). 3.1.3 The reinforcement in concrete structures shall comply with the current national standard Code for Design of Concrete Structures (GB 50010). 3.2 Steel, welding materials and fasteners 3.2.1 Q285B steel and Q355B steel should be used for greenhouse jade structure, and Q195, Q215 and Q235A steel can be used if there is a reliable basis, and their quality should comply with the current national standard K Carbon Structural Steel GB/T700 and Low Alloy High Strength Structural Steel GB/T1591 respectively. 3.2.2 Welding materials shall meet the following requirements: 1 Manual welding electrodes shall comply with the current national standard Non alloy Steel and Fine Grain Steel Electrodes (GB/T5117). The type of welding rod shall be compatible with the strength of steel. 2 The automatic welding wire shall comply with the current national standards Steel Wire for Fusion Welding (GB/T14957), Non alloy Steel and Fine Grain Steel Solid Welding Wire for Gas Metal Arc Welding (GB/T8110), Non alloy Steel and Fine Grain Steel Flux cored Wire (GB/T10045) and High Strength Steel Flux cored Wire (GB/T 17493). 3 Submerged arc welding wires and fluxes shall comply with the current national standards Classification Requirements for Solid Welding Wires, Flux cored Wires and Flux Combinations of Non alloy Steel and Fine Grain Steel for Submerged Arc Welding (GB/T5293) and Classification Requirements for Solid Welding Wires, Flux cored Wires and Wire Flux Combinations of Thermal Strength Steel for Submerged Arc Welding (GB/T12,470). The welding wires and fluxes shall be compatible with the strength of the main metal. 3.3 Aluminum alloy profile and glass 3.3.1. '6XXX series aluminum alloy should be used as the aluminum alloy profile for greenhouse. The alloy brand, supply status, chemical composition and mechanical properties of the profile should comply with the current national standard Aluminum Alloy Building Profiles Part 1: Base Materials GB 5237.1. 3.3.2 The glass selected for the greenhouse should conform to the current industry standard Technical Specification for Application of Architectural Glass JGJ 113. 3.4 Design index 3.4.1 The design value of steel strength shall be adopted according to Table 3.4.1. 4 Basic regulations 4.1 Design principles 4.1.1 This standard adopts the limit state design method based on probability theory, which is calculated by partial coefficient design expression. 4.1.2 Except for non agricultural production greenhouses used for sightseeing, picking or exhibition, the seismic action shall be calculated in the structural design of agricultural production glass greenhouses in areas with seismic fortification intensity of 8 degrees (0.30g) or above. 4.1.3 The main structure of the greenhouse shall be designed according to the limit state of bearing capacity. When the design service life is 20a, it shall also be designed according to the limit state of normal use 4.1.4 When the structural members are designed according to the limit state of bearing capacity, the basic combination of load effect shall be adopted according to the current national standard Load Code for Agricultural Greenhouse Structures (GB/T51183), and shall be calculated according to the following formula: Structure importance coefficient, not less than 0.90; S - design value of load effect combination (N/mm2); R. - Design value of bearing capacity of structural members (N/mm2). 4.1.5 When the structural members are designed according to the serviceability limit state, the deformation shall be calculated according to the current national standard Load Code for Agricultural Greenhouse Structures (GB/T51183), using the standard combination of load effects, and shall comply with the provisions of Section 4.4 of this standard. 4.1.6 When the width thickness ratio of the structural member section meets the limit value specified in Table 4.3.3 of this standard, the strength of the structural member can be calculated as net area, and the stability and deformation can be calculated as gross section. 4.2 Load action 4.3 Structural requirements 4.3.1 The wall thickness of greenhouse steel structure members shall meet the following requirements: 1. The wall thickness of main load-bearing components shall not be less than 1.5 mm; 2 The wall thickness of cold-formed thin-walled steel used for roof and wall purlins should not be less than 1.5mm; 3 When the steel plate gutter is used as a stressed member, the wall thickness should not be less than 2.0mm; The wall thickness shall not be less than 1.5mm when it is not used as a stressed member; 4 The wall thickness of components used for support shall not be less than 1.5mm; 5 The quality grade of steel plate thickness shall not be lower than Grade B. 4.3.2 The slenderness ratio of greenhouse steel structure members shall meet the following requirements: 1 The slenderness ratio of compression members should not be greater than that specified in Table 4.3.2-1. 5 Structural form and layout 5.1 Structure 5.1.1 Greenhouses can be divided into plastic greenhouses, solar greenhouses and multi span greenhouses. 5.1.2 Plastic greenhouses (Fig. 5.1.2) can be divided into column and column free plastic greenhouses according to whether there are columns in the room, and can be divided into shoulder type and floor type plastic greenhouses according to the shape. 5.2 Structural layout 5.2.1 The space between deformation joints of greenhouse structure shall be determined according to the following factors: 1 The longitudinal temperature range of multi span greenhouse shall not be greater than 300m; The transverse temperature range shall not be greater than 150m; When the back wall of the solar greenhouse is brick masonry, the temperature range shall not be greater than 100m; 2 When the soil types at the greenhouse construction site are different and the bearing capacity varies greatly, the deformation joints should be set according to the geological conditions; 3 When the height difference between adjacent positions of the greenhouse is 2.0m or more or different building forms are used, deformation joints shall be set at the structural changes; 4 The width of deformation joint shall not be less than 1000m. 5.2.2 The layout of roof and wall purlins should be determined according to the installation requirements of roof and wall covering materials, equipment dimensions and other factors. 5.3 Support layout 5.3.1 The layout of plastic shed supports shall meet the following requirements: 1. The longitudinal tie bar shall be set at least three times, and the spacing shall not be greater than 2m 2 When the length of the plastic shed is not more than 50m, diagonal bracing shall be set in 3~5 bays starting from the first bay at the gable end; When the length is more than 50m, a group of diagonal braces should be added in the middle of the plastic shed, and the included angle between the diagonal brace and the arch bar should not be less than 25 °. 5.3.2 The support layout of solar greenhouse shall comply with the following requirements: 1 The spacing of longitudinal tie bars should not be greater than 2m, and longitudinal tie bars should be set at the ridge; 2. When the rear wall is of steel frame structure and non frame form, diagonal braces should be set at both ends, and the spacing of diagonal braces should not be greater than 50m; 6 Structural calculation 7 Component calculation and connection structure 8 Glass and its supporting frame Appendix A Section Characteristics of Common Greenhouse Members Appendix B Approximate Calculation Formula for Section Characteristics of Common Greenhouse Members Appendix C Typical Connection Nodes of Greenhouse Structure Description of words used in this standard List of reference standards

Contents of GB/T 51424-2022

Foreword 1 General 2 Terms and symbols 3 Materials 4 Basic regulations 5 Structural form and layout 6 Structural calculation 7 Component calculation and connection structure 8 Glass and its supporting frame Appendix A Section Characteristics of Common Greenhouse Members Appendix B Approximate Calculation Formula for Section Characteristics of Common Greenhouse Members Appendix C Typical Connection Nodes of Greenhouse Structure Description of words used in this standard List of reference standards