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GB 50009-2012 PDF English (GB 50009-2001: Older version)Standard Briefing:Stadard ID: GB 50009-2012Stadard Title: Load code for the design of building structures Price (USD): 125 Lead time: 9 seconds. Download online + auto-delivery via email (Full-Copy in True-PDF & Invoice). Click to see step-by-step procedure Status: Valid Evolution and Historical Versions:
Excerpted PDF Sample:Full copy of true-PDF will be delivered in 9 seconds upon purchase: GB 50009-2012Similar Standards:GB 50843 GB 50728 JGJ 7 GB/T 25181Contents and Excerpt:GB 50009-2012 GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA UDC P GB 50009-2012 Load Code for the Design of Building Structures ISSUED ON: MAY 28, 2012 IMPLEMENTED ON: OCTOBER 1, 2012 Issued by: Ministry of Housing and Urban-Rural Construction of the People’s Republic of China; General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China.Table of Contents1 General Provisions ... 8 2 Terms and Symbols ... 9 2.1 Terms ... 9 2.2 Symbols ... 11 3 Classification and Combination of Loads ... 15 3.1 Classification of Loads and Representative Values of Loads ... 15 3.2 Combination of Loads ... 15 4 Permanent Load ... 20 5 Live Load on Floors and Roofs ... 21 5.1 Uniformly Distributed Live Loads on Floors in Civil Buildings ... 21 5.2 Live Loads on Floors in Industrial Buildings ... 23 5.3 Live Loads on Roofs ... 24 5.4 Ash Load on Roofs ... 25 5.5 Construction and Maintenance Loads, Horizontal and Vertical Loads on Railings ... 26 5.6 Dynamic Coefficient ... 27 6 Crane Load ... 28 6.1 Vertical and Horizontal Crane Loads ... 28 6.2 Combination of Multi-cranes ... 28 6.3 Dynamic Coefficients of Crane Loads ... 29 6.4 Combination Value, Frequent Value and Quasi-permanent Value of Crane Load ... 29 7 Snow Load ... 30 7.1 Characteristic Value of Snow Load and Reference Snow Pressure ... 30 7.2 Distribution Factor for Roof Snow Load ... 30 8 Wind Load ... 34 8.1 Characteristic Value of Wind Load and Reference Wind Pressure ... 34 8.2 Exposure Factor for Wind Pressure ... 35 8.3 Shape Factor of Wind Load ... 36 8.4 Along-wind Vibration and Dynamic Response Factor ... 57 8.5 Across-wind and Wind-induced Torsional Vibration ... 59 8.6 Gust Factor ... 61 9 Thermal Action ... 62 9.1 General Requirements ... 62 9.2 Reference Air Temperature ... 62 9.3 Uniform Temperature Action... 63 10 Accidental Load ... 64 10.1 General Requirements ... 64 10.2 Explosion ... 64 10.3 Impact ... 65 Appendix A Self-weight of Commonly Used Materials and Members ... 66 Appendix B Reduction Factor of Fire Engine Load Accounting for the Influence of Covered Soil ... 78 Appendix C Determination Method of Equivalent Uniformly Distributed Live Loads on Floors ... 79 Appendix D Live Loads on Floors of Industrial Buildings ... 83 Appendix E Determination Method of Reference Snow Pressure, Wind Pressure and Temperature ... 88 Appendix F Empirical Formula for Fundamental Natural Period of Structures ... 118 F.1 High-rise Structures ... 118 F.2 Tall Buildings ... 120 Appendix G Approximate Vibration Mode Shape of Structures ... 121 Appendix H Equivalent Wind Load for Across-wind and Torsional Vibration ... 123 H.1 Equivalent Wind Load for Across-wind Vibration of Structures of Circular Section ... 123 H.2 Equivalent Wind Load for Across-wind Vibration of Structures of Rectangular Section . 124 H.3 Equivalent Wind Load for Torsional Vibration of Structures of Rectangular Section ... 129 Appendix J Acceleration of Wind Induced Along-wind and Across-wind Vibration for Tall Buildings ... 131 J.1 Calculation of Acceleration of Along-wind Vibration ... 131 J.2 Calculation of Acceleration of Across-wind Vibration ... 132 Explanation of Wording in this Code ... 134 List of Quoted Standards ... 135General Provisions1.0.1 This code is formulated with a view to adapting the need of the building structure design and meeting the requirements of safety and usability, economy and rationality. 1.0.2 This code is applicable to the structural design of building engineering. 1.0.3 This code is formulated in accordance with the basic principles specified in the national standard “Unified Standard for Reliability Design of Engineering Structures” GB 50153−2008. 1.0.4 The actions concerned in the building structure design shall cover direct action (load) and indirect action. This code only specifies load and thermal action, and the provisions for the relevant variable load are also applicable to the thermal action. 1.0.5 The loads concerned in the building structure design shall not only comply with this code, but also those in the current relevant ones of the nation. 3 Classification and Combination of Loads 3.1 Classification of Loads and Representative Values of Loads 3.1.1 The loads of the building structures may be classified into: 1 Permanent load, including structure self-weight, soil pressure, prestress, etc.. 2 Variable load, including live load on floor, live load on roof and ash load, crane load, wind load, snow load, thermal action, etc.. 3 Accidental load, including explosive force, impact force, etc.. 3.1.2 In the design of building structures, the different loads shall adopt different representative values according to the following requirements: 1 For permanent load, the characteristic value shall be its representative value; 2 For variable load, the characteristic value, combination value, frequent value or quasi- permanent value shall be its representative value according to the design requirements; 3 For accidental load, its representative value shall be determined according to the use characteristics of the building structures. 3.1.3 The determination of the representative value of variable load shall adopt 50-yeardesign reference period. 3.1.4 The characteristic values of loads shall be adopted according to the requirements of each chapter of this code. 3.1.5 In the design of limit state of bearing capacity or the design of limit state of normal use according to the characteristic combination, for variable load, the combination value or characteristic value shall be its representative value according to the specified load combination. The combination value of variable load shall be the characteristic value of variable load multiplied by the load combination value coefficient. 3.1.6 In the design of limit state of normal use according to frequent combination, for variable load, the frequent value or quasi-permanent value shall be its representative value; in the design according to quasi-permanent combination, the quasi-permanent value of variable load shall be its representative value. The frequent value of variable load shall be the characteristic value of variable load multiplied by the frequent value coefficient. The quasi-permanent value of variable load shall be the characteristic value of variable load multiplied by the quasi-permanent value coefficient. 3.2 Combination of Loads 3.2.1 In the design of the building structures, load combination shall be carried out according to the limit state of bearing capacity and the limit state of normal use respectively based on the loads possibly emerging simultaneously on the structure during the use process, and the respective most unfavorable combination shall be taken for design. 3.2.2 For the limit state of bearing capacity, the effect design value of load combination shall be 7 Snow Load 7.1 Characteristic Value of Snow Load and Reference Snow Pressure 7.1.1 The characteristic value of snow load on roofs in horizontal projection plane shall be calculated according to the following formula: Sk=μrs0 (7.1.1) Where Sk——The characteristic value of snow load (kN/m2); μr——The distribution factor for roof snow load; s0——The reference snow pressure (kN/m2). 7.1.2 The reference snow pressure shall adopt the snow pressure with 50-year recurrence interval, which is determined according to the method specified in this code; for the structure sensitive to snow load, the snow pressure with 100-year recurrence interval shall be adopted. 7.1.3 The reference snow pressure of all the cities throughout the country shall be adopted according to the value with a recurrence interval R of 50 years in Table E.5 of Appendix E of this code. Where the reference snow pressure of a city or construction site is not given in Table E.5 of this code, the reference snow pressure shall be determined through statistical analysis according to the method specified in Appendix E of this code, in accordance with the local annual maximum snow pressure or snow depth data, and on the basis of the definition of reference snow pressure; and the analysis shall consider the influence of sample size. In the absence of local snow pressure and snow depth data, the reference snow pressure may be determined through comparative analysis on meteorological and topographic conditions according to the reference snow pressure or long-term data specified for nearby areas, or determined approximately according to Annexed Figure E.6.1 Distribution Map of Reference Snow Pressure throughout the Country in Appendix E of this code. 7.1.4 The snow load in mountain area shall be determined through actual investigation. In the absence of measured data, the snow load may be adopted according to the snow load value of local adjacent open and flat ground surface multiplied by a coefficient of 1.2. 7.1.5 The combination value coefficient of snow load may take 0.7; the frequent value coefficient may take 0.6; the quasi-permanent value coefficient shall take 0.5, 0.2 and 0 respectively according to Zones I, II and III of snow load; the snow load zones shall be adopted in accordance with those specified in Appendix E.5 or Annexed Figure E.6.2 of this code. 7.2 Distribution Factor for Roof Snow Load 7.2.1 The distribution factor for roof snow load shall be adopted in accordance with those specified in Table 7.2.1 according to the roof type of different categories. 7.2.2 In the design of building structures and supporting members of roofs, the snow distribution condition shall be adopted according to the following requirements: 1 The roof slab and purlin shall be adopted according to the most unfavorable condition of nonuniform snow distribution; 8 Wind Load 8.1 Characteristic Value of Wind Load and Reference Wind Pressure 8.1.1 The characteristic value of wind load vertical to the building surface shall be determined according to the following requirements: 1 In the calculation of main load-carrying structures, the characteristic value of wind load shall be calculated according to the following formula: wk=βzμsμzw0 (8.1.1-1) Where wk——The characteristic value of wind load (kN/m2); βz——The dynamic response factor at z height; μs——The shape factor of wind load; μz——The exposure factor for wind pressure; w0——The reference wind pressure (kN/m2). 2 In the calculation of enclosure structures, the characteristic value of wind load shall be calculated according to the following formula: wk=βgzμslμzw0 (8.1.1-2) Where βgz——The gust factor at z height; μsl——The local shape factor of wind load. 8.1.2 The reference wind pressure shall adopt the wind pressure with 50-year recurrence interval, which is determined according to the method specified in this code, but shall not be less than 0.3kN/m2. For the tall buildings, high-rise structures and other structures sensitive to wind load, the reference wind pressure value shall be increased properly, shall meet the requirements of the relevant code for the design of structures. 8.1.3 The reference wind pressure of all the cities throughout the country shall be adopted according to the value with a recurrence interval R of 50 years in Table E.5 of Appendix E of this code. Where the reference wind pressure of a city or construction site is not given in Table E.5 of this code, the reference wind pressure shall be determined through statistical analysis according to the method specified in Appendix E of this code and in accordance with the definition of reference wind pressure and the local annual maximum wind speed data; and the analysis shall consider the influence of sample size. In the absence of local wind speed data, the reference wind pressure may be determined through comparative analysis on meteorological and topographic conditions according to the reference wind pressure or long-term data specified for nearby areas, or determined approximately according to Annexed Figure E.6.3 Distribution Map of Reference Wind Pressure throughout the Country in Appendix E of this code. 8.1.4 The combination value coefficient, frequent value coefficient and quasi-permanent value coefficient of wind load may take 0.6, 0.4 and 0.0 respectively. 3 Other conditions shall be valued according to μsl of open buildings. Note: 1 The opening ratio of dominant opening refers to the ratio of the area of single dominant opening to the whole area of this wall; 2 μsl shall take the value of corresponding dominant opening position. 8.3.6 For the wind tunnel test of building structures, the test equipment, test methods and data processing shall meet the requirements of the relevant codes. 8.4 Along-wind Vibration and Dynamic Response Factor 8.4.1 For the buildings with height greater than 30m and height-width ratio greater than 1.5 and various high-rise structures with fundamental natural period T1 greater than 0.25s, the along-wind vibration influence of wind pressure fluctuation on structures shall be considered. The response calculation of along-wind vibration shall be carried out according to the theory of random vibration of structures. For the structures meeting the requirements of Article 8.4.3 of this code, the along-wind load may be calculated through dynamic response factor method. Note: 1 The natural vibration period of structures shall be calculated according to the structural dynamics; the approximate fundamental natural period T1 may be calculated according to Appendix F; 2 The acceleration of along-wind vibration of tall buildings may be calculated according to Appendix J of this code. 8.4.2 For the flexible roof structures sensitive to wind or with span greater than 36m, the wind vibration influence of wind pressure fluctuation on structures shall be considered. The wind vibration response of roof structures should be determined through calculation according to the random vibration theory based on the wind tunnel test results. 8.4.3 For general vertical cantilever structures, e.g. Tall buildings and high-rise structures such as framework, tower frame and chimney, only the influence of the first vibration mode of the structures may be considered; the along-wind load of the structures may be calculated according to Formula (8.1.1-1). The dynamic response factor βz at z height may be calculated according to the following formula: Z10z 121 RBgI (8.4.3) Where g——The peak factor, taking 2.5; I10——The nominal turbulence intensity of 10m height, taking 0.12, 0.14, 0.23 and 0.39 corresponding to Category A, B, C and D terrain roughness respectively; R——The resonant component factor of fluctuating wind load; Bz——The background component factor of fluctuating wind load. 8.4.4 The resonant component factor of fluctuating wind load may be calculated according to the following formula: 3/42 1 )1......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al. |