【正文】 ccording to actual conditions Live load on flooring considered as equivalent evenly distributed load Library store and archive store Other civilian buildings The seismic influence coefficient of building structures shall be taken as per Fig. on the basis of the near earthquake, far earthquake, site class and selfvibration period of structure, and its lower limit shall be no less than 20% of the maximum value。 II. In any structure with angular antilateral force members, the horizontal seismic action in the direction of each antilateral member shall be taken into consideration。 Design specification for concrete structures GBJ 10 – 89 In the design for antiseismic 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 。 IV. Provisions shall be made to increase the antiseismic capacity at possible weak portions. — 4 — Structural Materials Antiseismic design specification for buildings GBJ 11 – 89 Any special requirement of the antiseismic structure on materials and construction quality shall be indicated in the design documents. The performance parameters of structural materials shall ply with the following minimum requirements: I. The strength grade of clay bricks shall be no lower than , and that of mortar for the brick masonry not lower than 。 II. Such consequences as damage to part of the structure or members resulting in the loss of antiseismic capacity or the bearing capacity of the gravitational force in the whole system shall be avoided。 for buildings requiring supplementary calculation using timehistory analysis method, the relevant dynamic parameters of the soil and the site covering layer thickness shall also be provided according to the design requirements. In the antiseismic proof calculation for natural ground foundation, the antiseismic bearing capacity of foundation soil shall be calculated by multiplying the foundation soil static bearing capacity with foundation soil antiseismic bearing capacity adjustment coefficient. The antiliquefaction provision for the ground foundation shall be determined in a prehensive 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 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 — 3 — foundation. Antiliquefaction provisions Table Building Class Liquefaction grade of ground foundation Slight Medium Serious B Liquefaction settlement shall be partially eliminated, or make treatment to the foundation and superstructure Liquefaction settlement shall be totally eliminated, or liquefaction settlement is partially eliminated plus treatment to the foundation and superstructure Liquefaction settlement shall be totally eliminated. C Treatment to the foundation and superstructure, and it is also possible not to take any provision Treatment to the foundation and superstructure, or provision with higher requirements Liquefaction settlement shall be totally eliminated, or liquefaction settlement is partially eliminated plus treatment to the foundation and superstructure D It is permissible not to take any provision It is permissible not to take any provision Treatment to the foundation and superstructure, or other economic provisions Building Layout and Structural Type Selection Antiseismic design specification for buildings GBJ 11 – 89 If a building with plicated shape is not provided with any antiseismic 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 antiseismic capacity。 — 1 — Section VI Antiseismic Design for Buildings 1. Basis and Classification of Antiseismic Protection Antiseismic design specification for buildings GBJ 11 – 89 The antiseismic 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. Antiseismic protection classification standard for buildings GB 50223 – 95 The antiseismic 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 ply 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 singlestoreyed warehouses or similar buildings with storage of lowvalued goods and little human activity. The antiseismic protection standard for different classes of buildings shall ply with the following requirements: F