工程建设标准强制性条文CPECSB6房屋建筑部分（英文版）.doc

Section VI Anti-seismic Design for Buildings1. Basis and Classification of Anti-seismic ProtectionAnti-seismic design specification for buildings GBJ 11 891.0.3 The anti-seismic protection intensity shall be determined with review and approval according to the power of authority specified by the state and documents (drawings) issued by the state.Anti-seismic protection classification standard for buildings GB 50223 953.0.2 The anti-seismic protection classifications for buildings shall be in four classes of A, B, C and D according to the importance of their application functions, and their classification shall comply with the following requirements: Class A buildings shall be those which will have serious impact to the society and huge loss to national economy if damaged in an earthquake, or which have special requirements. Class B buildings shall be those the application functions of which must not be interrupted or should be restored as soon as possible, and which will have major impact to the society and great loss to national economy if damaged in an earthquake. Class C buildings shall be those with average influence if damaged in an earthquake, and other buildings not included in Classes A, B and D. Class D buildings shall be those which will not affect buildings of Classes A, B and C and which will have little social impact or economic loss if damaged or collapsed in an earthquake. Generally they include single-storeyed warehouses or similar buildings with storage of low-valued goods and little human activity.3.0.3 The anti-seismic protection standard for different classes of buildings shall comply with the following requirements: For buildings of Class A, design shall be made for one degree higher than the protection intensity (including seismic action and anti-seismic provisions). For buildings of Class B, the seismic action shall be calculated on the basis of the anti-seismic protection intensity of the region. The anti-seismic provisions shall be designed as one degree higher for protection intensity of degree 68, and shall be enhanced for degree 9. For Class B buildings with relatively small sizes, the anti-seismic provisions can be designed as for the anti-seismic protection intensity of the region if economically reasonable structural systems with good anti-seismic performance are used.The class of anti-seismic provisions shall not be increased for ground foundations of Class B buildings. For buildings of Class C, both the seismic action and anti-seismic provisions shall be designed on the basis of the protection intensity of the region. For buildings of Class D, normally no reduction shall be made for the seismic action, and for protection intensity degree 79, the anti-seismic provisions shall be designed at one degree lower than the protection intensity of the region, and will not be lowered for intensity degree 6.2. Basic Provisions2.1 Seismic Impact, Site and Ground FoundationAnti-seismic design specification for buildings GBJ 11 892.1.2 A building site shall be selected on the basis of the need of the project and the mastery of relevant data on seismic activities and engineering geology, and a comprehensive assessment shall be made. When it is not possible to avoid an unfavorable ground section, appropriate anti-seismic provisions shall be made; Buildings of Classes A, B and C shall not be build on dangerous ground sections.2.1.3 For building site of Class I, except for buildings of Class D, the anti-seismic structural provisions can be taken at one degree lower than the original intensity, and the seismic action shall still be calculated according to the original intensity, provided that no reduction shall be made in structural provisions for degree The building sites shall be classified into four categories according to ground soil types and thickness of site coverage layer.3.1.6 In the site geological survey, the site shall be divided into favorable, unfavorable and dangerous sections to the building according to the actual needs, and the site class for the building and rock and soil seismic stability (e.g. landslide, collapse) assessment shall be provided; for buildings requiring supplementary calculation using time-history analysis method, the relevant dynamic parameters of the soil and the site covering layer thickness shall also be provided according to the design requirements.3.2.2 In the anti-seismic proof calculation for natural ground foundation, the anti-seismic bearing capacity of foundation soil shall be calculated by multiplying the foundation soil static bearing capacity with foundation soil anti-seismic bearing capacity adjustment coefficient.3.3.6 The anti-liquefaction provision for the ground foundation shall be determined in a comprehensive manner on the basis of the importance of the building and the liquefaction grade of the ground foundation and in conjunction with the actual conditions, Table 3.3.6 shall be followed when the liquefied soil layer is relatively flat and homogenous. Except for buildings of Class D, untreated liquefied soil layer shall not be used as the load bearing layer for the natural ground foundation.Anti-liquefaction provisionsTable 3.3.6Building ClassLiquefaction grade of ground foundationSlightMediumSeriousBLiquefaction settlement shall be partially eliminated, or make treatment to the foundation and superstructureLiquefaction settlement shall be totally eliminated, or liquefaction settlement is partially eliminated plus treatment to the foundation and superstructureLiquefaction settlement shall be totally eliminated.CTreatment to the foundation and superstructure, and it is also possible not to take any provisionTreatment to the foundation and superstructure, or provision with higher requirementsLiquefaction settlement shall be totally eliminated, or liquefaction settlement is partially eliminated plus treatment to the foundation and superstructureDIt is permissible not to take any provisionIt is permissible not to take any provisionTreatment to the foundation and superstructure, or other economic provisions2.2 Building Layout and Structural Type SelectionAnti-seismic design specification for buildings GBJ 11 892.2.2 If a building with complicated shape is not provided with any anti-seismic joint, its local stress and deformation concentration and torsion effect shall be estimated, and its portion likely to be damaged be determined, to take measures for better anti-seismic capacity; when anti-seismic joints are provided, sufficient width shall be provided according to the intensity, ground class and building type, and the superstructures on both sides of the joint shall be completely separated.All expansion joints and settlement joints shall comply with the requirements for anti-seismic joints.2.3.2 An anti-seismic structural system shall comply with all the following requirements:I. There shall be explicit calculation sketches and reasonable transmission route for the seismic actions;II. Such consequences as damage to part of the structure or members resulting in the loss of anti-seismic capacity or the bearing capacity of the gravitational force in the whole system shall be avoided;III. It shall have necessary strength, good deformation ability and energy dissipation ability;IV. Provisions shall be made to increase the anti-seismic capacity at possible weak portions.2.3 Structural MaterialsAnti-seismic design specification for buildings GBJ 11 892.5.1 Any special requirement of the anti-seismic structure on materials and construction quality shall be indicated in the design documents.2.5.2 The performance parameters of structural materials shall comply with the following minimum requirements:I. The strength grade of clay bricks shall be no lower than MU7.5, and that of mortar for the brick masonry not lower than M2.5;III. The strength grade of concrete shall be no lower than C30 for frame beams, columns and nodes in case of anti-seismic class I, no lower than C15 for structural columns, stems, girths and expanded foundations, and no lower than C20 for other types of members;Design specification for concrete structures GBJ 10 898.2.3 In the design for anti-seismic grades I and II, for the selection of longitudinal load bearing reinforcing bars in a frame structure, the measured strength value as obtained in the inspection shall also meet the following requirements:I. The ratio of measured tensile strength value to the measured yield strength value of the bars shall be no less than 1.25;II. The ratio of measured yield strength value of the bars to the standard strength value of the bars shall be no greater than 1.25 for design with anti-seismic grade I, and shall be no greater than 1.4 for design with anti-seismic grade II.Technical regulations on structural steel for high-rise civilian buildings JGJ 99 982.0.3 The strength to yield ratio of anti-seismic structural steel shall be no less than 1.2, and the elongation shall be greater than 20%.2.4 Seismic Action and Anti-seismic Proof Calculation for StructuresAnti-seismic design specification for buildings GBJ 11 894.1.1 The seismic action of various types of building structures shall be taken into consideration according to the following principles:I. Under normal conditions, horizontal seismic action can be taken into consideration in both main axes directions of the building structure, and anti-seismic proof calculation performed, the horizontal seismic action in each direction shall be fully undertaken by the anti-lateral force members in that direction;II. In any structure with angular anti-lateral force members, the horizontal seismic action in the direction of each anti-lateral member shall be taken into consideration;III. For structures with apparent uneven or asymmetric mass and rigidity distribution, the torsion effect of horizontal seismic action shall be taken into consideration;IV. The vertical seismic action shall be taken into consideration for large span structures and long cantilever structures for intensity 8 and 9 degrees, and for high-rise buildings for intensity 9 degrees.4.1.3 In the calculation of seismic action, the gravitational load characteristic value of the building shall be taken as the sum of the standard value of the self-weight of the structure and members and accessories and the combined value of all the variable loads. The combined value coefficient of all the variable loads shall be taken from Table 4.1.3.Combined value coefficientTable 4.1.3Type of variable loadCombined value coefficientSnow load0.5Live load on roofingNot taken into considerationLive load on flooring considered according to actual conditions1.0Live load on flooring considered as equivalent evenly distributed loadLibrary store and archive store0.8Other civilian buildings The seismic influence coefficient of building structures shall be taken as per Fig. 4.1.4 on the basis of the near earthquake, far earthquake, site class and self-vibration period of structure, and its lower limit shall be no less than 20% of the maximum value; in the sectional anti-seismic proof calculation, the maximum value for horizontal seismic influence coefficient shall follow Table 4.1.4-1.Max. value for horizontal seismic influence coefficient in the sectionalanti-seismic proof calculation Table 4.1.4-1Intensity6789amax0.040.080.160.32Fig. 4.1.4 Seismic influence coefficient curveaSeismic influence coefficient;amaxMax. value of seismic influence coefficient;TSelf vibration period of structure;TgCharacteristics period, to be taken from Table 4.1.4-2 according to site type and near and far earthquakes.Characteristics period value (s)Table 4.1.4-2Near or far earthquakeType of siteIIIIIIIVNear earthquake0.200.300.400.65Far earthquake0.250.400.550.854.1.6 The anti-seismic proof calculation for structures shall comply with the following provisions:I. For buildings for intensity degree 6 (except tall high-rise buildings on type IV site), sectional anti-seismic proof calculation can be omitted, but it shall comply with the requirements of anti-seismic provisions;II. Sectional anti-seismic proof calculation shall be performed for tall high-rise buildings on type IV site for intensity degree 6 and for structures for intensity degree 7 or above.4.4.1 The basic combination of seismic action effect and other load effect in the structural members shall be calculated using the following formula:S=GCGGE + EhCEhEhk + EvCEvEvk + wwCwwk(4.4.1)Where SDesign value of combined internal force of the structural member, including the design value of combined bending moment, axial force and shearing force;gGGravitational load partial safety factor, normally taken as 1.2, and 1.0 can be taken when the gravitational load effect is favorable to the bearing capacity of the structure;gEh, gEvRespectively the partial safety factor of horizontal and vertical seismic action, and shall be taken from Table 4.4.1;gwWind load partial safety factor, shall be taken as 1.4;GEGravitational load characteristics value;EhkHorizontal seismic action standard value;EvkVertical seismic action standard value;wkWind load standard value;ywWind load combined value coefficient, not considered for ordinary structures, and taken as 0.2 for relatively tall high-rise buildings;CG ,CEh ,CEv ,CwRespectively the action effect coefficient of gravitational load, horizontal seismic action, vertical seismic action and wind load, and they should be multiplied with corresponding amplifying coefficient or adjustment coefficient.Partial safety factor of seismic actionTable 4.4.1Seismic actiongEhgEvOnly taken into account horizontal seismic action1.3Not taken into accountOnly taken into account vertical seismic actionNot taken into account1.3Both horizontal and vertical seismic action are taken into account.2 The following design expression shall be adopted for the sectional anti-seismic proof calculation for structural members:SR/gRE(4.4.2)Where gRE Bearing capacity anti-seismic adjustment coefficient, shall be taken from Table 4.4.2;RBearing capacity design value of structural member.Bearing capacity anti-seismic adjustment coefficientTable 4.4.2MaterialStructural memberLoading statusRESteelColumnsSupport between columns in structural steel factory buildings Support between columns in reinforced concrete factory buildingsWelding seam on membersDeflected compression1.0MasonryAnti-seismic walls with structural columns and stems at both endsOther types of anti-seismic wallsShearingShearing0.91.0Reinforced concreteBeamsColumns with axial compression ratio less than 0.15Columns with axial compression ratio not less than 0.15Anti-seismic wallsMembers of various typesBendingDeflected compressionDeflected compressionDeflected compressionShearing and Deflected tensile0.750.750.800.850.854.5.4 In the calculation of standard value of rarely encountered seismic action, the horizontal seismic influence coefficient shall be taken as per Fig. 4.1.4, and its maximum value shall be taken as per Table 4.5.4.Max. value of horizontal seismic influence coefficient for rarely encountered seismic actionTable 4.5.4Intensity789amax0.500.901.40Design and construction regulations for bent structures JGJ 7 913.4.1 In areas with anti-seismic design protection intensity of degrees 8 or 9, vertical anti-seismic proof calculation shall be performed for bent roofing structures.3.4.2 In areas with anti-seismic design protection intensity of degree 8, the horizontal anti-seismic proof calculation may be omitted for medium and small-span bent structures with peripheral supports; in areas with anti-seismic design protection intensity of degree 9, the horizontal anti-seismic proof calculation shall be performed for all bent structures.3. Anti-seismic Design for Concrete Structures3.1 Multi-storeyed and High-rise Reinforced Concrete BuildingsAnti-seismic design specification for buildings GBJ 11 896.1.3 Different anti-seismic grades shall be applied for reinforced concrete buildings according to the intensity, structural type and building height, and they shall comply with the corresponding requirements in calculation and structural provisions.In the frame anti-seismic wall structures, when the seismic tipping moment borne by the anti-seismic wall is not greater than 50% of the total seismic tipping moment of the structure, the anti-seismic grade of the frame section shall be determined as for frame structure.Note: “Grade I, II, III and IV” as referred to in this section is the abbreviated reference to “anti-seismic grade I, II, III and IV”.6.1.9 When assembled flooring and roofing is adopted for the frame anti-seismic wall structure, provisions shall be made to ensure the integrity of the building and the roofing and their reliable connection with the anti-seismic walls.6.1.14 The anti-seismic walls for the top storey, staircase and anti-lateral-force staircase of the building, longitudinal anti-seismic walls and gables of end rooms, as well as single limb walls, walls with small openings and the lower part of combined limb walls (the greater value of 1/8 of the wall limb total height and the wall limb width, and also be no less than the height of the up to the floor above the frame support level when there is frame support floor) shal