GB/T 51422-2021 English PDFUS$2059.00 · In stock
Delivery: <= 11 days. True-PDF full-copy in English will be manually translated and delivered via email. GB/T 51422-2021: (Technical Standards for Testing, Appraisal and Reinforcement of Building Metal Sheet Enclosure System) Status: Valid
Basic dataStandard ID: GB/T 51422-2021 (GB/T51422-2021)Description (Translated English): (Technical Standards for Testing, Appraisal and Reinforcement of Building Metal Sheet Enclosure System) Sector / Industry: National Standard (Recommended) Classification of Chinese Standard: P26 Word Count Estimation: 103,114 Issuing agency(ies): Ministry of Housing and Urban-Rural Development of the People's Republic of China; State Administration for Market Regulation GB/T 51422-2021: (Technical Standards for Testing, Appraisal and Reinforcement of Building Metal Sheet Enclosure System)---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order. 1 General 1.0.1 This standard is formulated in order to achieve technical reliability, safety and applicability, economical rationality, and quality assurance during the inspection, appraisal, reinforcement and transformation of building metal plate enclosure systems. 1.0.2 This standard applies to the detection, identification, reinforcement and renovation of new or existing building metal plate enclosure systems. 1.0.3 The detection, identification, reinforcement and transformation of building metal plate enclosure systems shall not only comply with this standard, but also comply with the current relevant national standards. 2 Terms and symbols 2.1 Terminology 2.1.1 metal building envelope system The prefabricated enclosure with the corresponding functions of the building is formed by using the pressed metal plate or the metal surface sandwich panel as the main plate of the roof, wall and other systems, connected by supporting components, combined with waterproof, thermal insulation, heat insulation, steam insulation and other structures. protection system. 2.1.2 profiled metal sheet Sheet metal is rolled, cold-bent, or bent to form a shaped sheet metal with a continuous wave or other shaped cross-section. 2.1.3 Appraisal of reliability A series of activities such as investigation, detection, analysis, checking and evaluation of the safety and usability of building metal plate enclosure systems. 2.1.4 target working life Identify the expected useful life of building sheet metal envelope systems. 2.1.5 assessment assessment According to the results of inspection, testing and analysis, the safety and usability of the building metal plate enclosure system are evaluated in accordance with the specified standards and methods. 2.1.6 Assessment items items of assessment A program for assessing the reliability of building sheet metal envelope systems and their components. 2.1.7 Appraisal unit According to the structural characteristics of the certified building metal plate enclosure system, the enclosure system is divided into one or several sections that can be independently identified, and each section is an identification unit. 2.1.8 component component The components of the metal plate enclosure system can be divided into components, connections, etc. 2.1.9 Component members A single component that bears various functions in the containment system, or refers to a certain component of the system. Including sheet metal, purlins, wall beams, etc. 2.1.10 connect connect A system that uses special brackets, self-tapping screws, rivets, nails, bolts, welding, occlusion, etc. to combine components together. 2.1.11 Attached facilities Maintenance access, ladders, fall prevention facilities, snow protection facilities, lightning protection facilities, photovoltaic systems, decoration systems, etc. for building metal plate enclosure systems. 2.1.12 Strengthening of metal building envelope system Measures such as reinforcement and partial replacement are adopted to improve the reliability of the building metal plate enclosure system, so that it has corresponding safety and usability. 2.1.13 Renovation of metal building envelope system Renovate or replace the original enclosure system to meet the functional requirements of the transformation. 2.2 Symbols 2.2.1 Main symbols of structural performance and action effect M—the design value of the maximum bending moment borne by a section; Mu - the design value of the bending capacity of the section; Mx, My——the sum of the design value of bending moment before strengthening and the design value of bending moment after strengthening around the x-axis and y-axis of the centroid of the reinforced section, respectively; We—effective section modulus; φbx——the overall stability coefficient of the beam; η—reinforcement strength correction factor; ηm—correction coefficient of strengthening strength of bending members; γ0——structural importance coefficient, whose value is consistent with the main structure. 2.2.2 Identification Rating au, bu, cu, du—the safety level of the component or its inspection items; Au, Bu, Cu, Du—the safety level of the identification unit or a part of it; as, bs, cs—serviceability level of the component or its inspection items; As, Bs, Cs—the usability grade of the identification unit or a part thereof; a, b, c, d - the reliability level of the component; A, B, C, D—the reliability level of the identification unit. 3 Basic Regulations3.1 General provisions 3.1.1 When one of the following conditions exists in the building metal plate enclosure system, reliability appraisal shall be carried out. 1 When there are quality defects or corrosion, leakage, damage, deformation, etc. that affect safety; 2 When the designed service life is reached and intended to continue to be used; 3 When the conditions of use or the change of the use environment are unfavorable to safety; 4 When a comprehensive overhaul is required; 5 When you intend to continue to use it after suffering a disaster or accident; 6.When routine maintenance checks find potential safety hazards; 7 When making modifications or alterations. 3.1.2 When one of the following conditions exists in the building metal plate enclosure system, special appraisal should be carried out. 1 When there are special requirements for maintenance and reconstruction; 2 When there is local damage affecting its normal use; 3 When there is doubt about the integrity and durability of the metal plate or when it needs to be dealt with; 4 When the supporting structural members, connections, etc. are subject to general corrosion, damage or other problems; 5 When there is vibration effect; 6 When long-term monitoring is required. 3.1.3 If the building metal plate enclosure system is identified as not meeting the requirements, it shall be reinforced. 3.2 Appraisal procedures and work content 3.2.1 The reliability appraisal of the building metal plate enclosure system should follow the clear appraisal purpose, scope, content, investigation, formulation of appraisal plan, inspection and testing, reliability analysis, reliability appraisal, submission of appraisal report and other workflows (Fig. 3.2.1) Proceed. 3.2.2 The purpose, scope and content of the appraisal of the building metal panel enclosure system shall be determined according to the reasons and requirements of the appraisal put forward by the entrusting party and the current status of the building metal panel enclosure system. 3.2.3 The investigation should include the following basic contents. 1 Review drawings and materials, including special reports, as-built drawings, as-built materials, inspection and observation records, maintenance records, drawings and materials of previous appraisal reinforcement and transformation, accident handling reports, etc.; 2 Investigate the historical situation of building metal plate enclosure system, including construction, maintenance, reinforcement, transformation, change of use, change of use conditions and disasters; 3 Investigate the site, investigate the basic situation, actual situation, use conditions, internal and external environment, accident records of the building metal plate enclosure system, check the problems that have been discovered so far, investigate or listen to the opinions of relevant personnel, etc. 3.2.4 The appraisal plan should be formulated according to the characteristics of the appraisal object, the investigation results, appraisal purpose and requirements, including the basis of the appraisal, work content and methods, work schedule and preparatory work to be completed by the entrusting party. 3.2.5 For inspection and testing, the following items should be selected according to the actual situation. 1 Check relevant documents and materials; 2 Material performance testing and analysis; 3 system performance testing and analysis; 4 Support structure inspection and testing; 5 Inspection and testing of connectors and panel systems; 6 Inspection and testing of auxiliary facilities; 7 When the deformation or damage of the main load-bearing structure or the foundation affects the building metal plate enclosure system, check and test according to relevant standards. 3.2.6 The reliability analysis shall be carried out according to the inspection and testing results, including the analysis and calculation of structural bearing capacity, the safety and usability analysis of the building metal plate enclosure system, and the cause analysis of existing defects, corrosion and damage. 3.2.7 In the reliability appraisal of the building metal plate enclosure system, if the inspection or testing data are found to be insufficient or inaccurate, supplementary inspection or testing should be carried out in time. 3.2.8 The reliability appraisal of the building metal plate enclosure system should be divided into two levels of components and appraisal units; the appraisal rating should include safety, usability and reliability grades; safety should be divided into four grades, usability should be Divided into three grades, the reliability should be divided into four grades, and should be evaluated according to Table 3.2.8.When it is not required to assess the reliability level, the safety and usability level assessment results can be directly given. 3.2.9 The appraisal procedure of the special appraisal can be carried out according to the reliability appraisal procedure, and the work content of the appraisal procedure should meet the requirements of the special appraisal. 3.2.10 A report should be submitted for testing and identification, and the preparation of the report should meet the requirements of Chapter 10 of this standard. 3.3 Identification and Rating Standards 3.3.1 The grading standards for each level of safety appraisal and rating of components and appraisal units of the building metal plate enclosure system shall be adopted in accordance with the provisions in Table 3.3.1. 3.3.2 The grading standards for each level of the usability appraisal and rating of components and appraisal units of the building metal panel enclosure system shall be adopted in accordance with the provisions in Table 3.3.2. 3.3.3 The grading standards for each level of reliability appraisal and rating of components and appraisal units of the building metal plate enclosure system shall be adopted in accordance with the provisions in Table 3.3.3. 3.4 Reinforcement and reconstruction requirements 3.4.1 Reinforcement and modification of building metal plate enclosure system may include reinforcement of enclosure support structure, reinforcement against wind exposure, reinforcement against trampling, anti-corrosion treatment, function modification of enclosure system, etc. 3.4.2 The reinforcement and reconstruction design of building metal plate enclosure system shall meet the following requirements. 1 The design scheme should be determined according to the influence of site conditions on the construction method and reinforcement effect; 2 The reinforcement should work in harmony with the original structure; 3 For structural damage caused by different influencing factors, corresponding prevention and control countermeasures should be put forward in the reinforcement design. 3.4.3 The design service life of reinforcement and reconstruction of building metal plate enclosure system shall be determined according to the following principles. 1 The design service life after reinforcement and reconstruction shall be agreed upon by the owner and the design unit, and should not be lower than the original remaining design service life; 2 In the case of local reinforcement and reconstruction, it shall be determined according to the influence of the original remaining design service life of the enclosure system structure on the design service life after reinforcement and reconstruction. 3.4.4 The acceptance of metal plate enclosure system reinforcement and reconstruction works shall be carried out after the construction is completed. 4 On-site investigation and inspection 4.1 Data investigation 4.1.1 Data investigation should include project overview, original design documents, special reports, as-built drawings, project acceptance documents, reconstruction data, meteorological data, etc. 4.1.2 When the information is incomplete, on-site investigation and actual measurement should be carried out. 4.2 Use load investigation 4.2.1 The standard value of self-weight of components shall be calculated and determined according to the standard value of self-weight per material unit according to the actual size of components and connections. When the information is complete and there is no significant deviation between the actual component size and the as-built drawing, the calculation can be carried out according to the as-built drawing. 4.2.2 Other standard values of dead loads borne by components shall be determined through on-site investigation. 4.2.3 The standard value of variable load borne by components shall be determined according to relevant standards such as the current national standard "Code for Building Structure Loads" GB 50009 and corresponding special reports. 4.2.4 The investigation of variable loads should still be based on regional characteristics. In areas prone to heavy snowfall, the local accumulation and sliding effects of snow loads should be investigated; in rainy areas, the water load of gutters caused by poor drainage or failure should be investigated ; In areas prone to strong winds, the effect of strong winds on unfavorable parts such as corners or overhangs should be investigated, and the influence of the dominant wind direction and the surrounding environment should be investigated; industrial plants that generate a lot of dust during the production process should investigate the dust load and local accumulation effect. 4.3 Status check 4.3.1 The status inspection shall include inspection of components and their connections, performance inspection, structure inspection and inspection of auxiliary facilities. 4.3.2 The inspection of components and their connections shall include the inspection of metal plates, purlins and wall beams and their connections. Inspection items should include manufacturing and installation deviations, corrosion defects and corrosion, component deformation, cracking or breaking, connection defects, etc. 4.3.3 For coastal areas or other areas prone to strong winds and atmospheric conditions, the connection status and local strengthening measures of edge parts such as gutters and cornices should be checked; for industrial plants, the connection status of the gable parts of the plant should also be checked; In areas subject to heavy snowfall, focus should be placed on areas that are prone to local loading, such as low-span roofs where high and low spans are connected; for structures located in corrosive, high-humidity, and coastal areas, emphasis should be placed on checking their anti-corrosion measures and component corrosion. 4.3.4 The inspection of anti-corrosion defects shall include the integrity of the topcoat, primer or coating and the percentage of damaged area. 4.3.5 The performance inspection shall include the waterproof, lightning protection, thermal and wind protection of the enclosure system, and the performance inspection shall meet the following requirements. 1 Waterproof inspection shall include metal plates and their joints, waterproof layer, flashing boards, ridge boards, corner boards, deformation joints, roof drainage systems, etc.; 2 The lightning protection inspection shall include air receptors, lead wires, grounding resistance, etc.; 3 The thermal inspection shall include metal plates, joints and expansion joints, etc.; 4 The windproof inspection shall include metal plates, flashing boards, detail nodes, etc. 4.3.6 Structural inspection shall include component and connection structure, waterproof structure, thermal insulation structure, vapor-proof structure, sound-proof structure and wind-proof structure. 4.3.7 The inspection items of the connection structure shall include structure layout, support system and connection structure of each structural unit, etc. 4.3.8 The inspection of auxiliary facilities shall include items such as structure, connection, impact on the safety of the main structural system and use functions.5 detection5.1 General provisions 5.1.1 The engineering inspection of the metal sheet enclosure system can be divided into the inspection of the newly built sheet metal enclosure system and the inspection of the existing sheet metal enclosure system. 5.1.2 In the following cases, the new metal plate enclosure system shall be inspected. 1 When using new materials, new installation techniques and new structural forms; 2 When the sampling test results of the construction quality fail to meet the design requirements; 3 When construction quality inspection is required; 4.When there are doubts or disputes about the quality of the project and further verification through testing is required; 5 Design or other conditions stipulated in relevant standards. 5.1.3 In the following situations, the existing metal plate enclosure system shall be inspected. 1 When conducting safety appraisal; 2 When carrying out reliability appraisal before overhaul or reconstruction; 3 When the design service life of the building is reached and needs to be continued to be used; 4 After major natural disasters or severe environmental erosion, it is necessary to assess its impact; 5 When there is doubt or dispute about reliability. 5.1.4 The engineering inspection of the metal plate enclosure system can be divided into laboratory inspection and on-site inspection, and the inspection at each stage shall comply with the requirements in Table 5.1.4. 5.1.5 According to the safety and functional requirements of the building metal plate enclosure system, the testing items should meet the requirements in Table 5.1.5. 5.1.6 After conducting the investigation and on-site investigation, the inspection unit shall formulate the inspection items and inspection plan for the metal plate enclosure system project according to the characteristics of the project and the requirements of the entrusting party. 5.1.7 The testing plan should include the following main contents. 1 Project overview; 2 The client's requirements or testing purpose; 3 Testing basis, mainly including the standards and relevant technical data on which the testing is based; 4 Test items, test methods and test quantities; 5 testing personnel and equipment; 6 testing progress plan; 7 The work that requires cooperation; 8 Safety and environmental protection measures during testing; 9 A description of the degree of local damage that occurred during on-site inspection, including a repair plan if necessary. 5.1.8 The tensile performance test of the connecting part of the fixed bracket between the metal plate and the supporting structure shall meet the requirements of Article 6.2.2 of this standard. In addition to the rivets, self-tapping screws or nails used for the tight connection between metal panels or between metal enclosures and supporting components in building metal panel enclosure systems in windy and coastal areas, they shall meet the requirements specified in Article 6.2.3 of this standard. In addition to the requirements of the article, it is also advisable to conduct laborato......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 51422-2021_English be delivered?Answer: Upon your order, we will start to translate GB/T 51422-2021_English as soon as possible, and keep you informed of the progress. The lead time is typically 7 ~ 11 working days. The lengthier the document the longer the lead time.Question 2: Can I share the purchased PDF of GB/T 51422-2021_English with my colleagues?Answer: Yes. 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