1.0.1 This specification has been formulated for the purpose to implement the working policy of taking prevention as the primary measure in antiseismic work, lessen the damaged to the structures caused by earthquakes, avoid casualties to people and reduce economic loss.
1.0.2 Structures for which ansiseismic design has been made in accordance with this specification, shall normally not be damaged or can continue to be used without repair after being impacted by an earthquake with an intensity lower than the protection level in the area; they might be damaged when subject to an earthquake at the guarding intensity, but may continue to be used after ordinary repair or without repair; and they will not collapse or be seriously damaged to the extent of endangering life or leading to major economic losses when the area is subject to an earthquake at an intensity one degree higher than the guarding intensity.
1.0.3 This specification is applicable to the antiseismic design for structures in areas with a guarding intensity of 6 to 9 degrees.
For the antiseismic design of structures in areas with a guarding intensity of 10 degrees or industries with special requirements, special study shall be conducted and the relevant regulations shall be implemented.
1.0.4 The antiseismic guarding intensity can be the basic seismic intensity specified in the current “Map of seismic intensity zoning of China”; for areas or factories and mines for which antiseismic protection classification has been made, antiseismic design can be made on the basis of the guarding intensity or seismic dynamic parameters for antiseismic design as confirmed in the antiseismic protection classification.
1.0.5 Structures shall be classified into the following four categories by their importance:
Class A ---- structures of special importance or with special requirements, and extremely serious consequences will be resulted if damaged in an earthquake;
Class B ---- important structures, which, if damaged in an earthquake, may lead to serious consequences such as massive casualty, serious secondary disaster, long term shutdown of important factories and mines;
Class C ----- structures other than those in Classes A, B and D;
Class D ---- secondary structures which are unlikely to cause personnel injury or death or sizable economic loss when damaged by an earthquake.
1.0.6 The antiseismic design for structures of all classes shall meet the following requirements:
1.0.6.1 The seismic action of Class A structures shall be calculated according to the specifically studied seismic dynamic parameters for antiseismic design; the seismic action of other classes of structures shall be calculated according to the guarding intensity in the area, and it is not necessary to perform calculation on seismic action for those with a guarding intensity of degree 6, unless otherwise specified in this specification.
1.0.6.2 For structures of Class A, special antiseismic measures shall be adopted; for structures of Class B, antiseismic measures can be adopted at one degree higher than the guarding intensity, provided that it should be made higher as appropriate for a guarding intensity of degree 9; for structures of Class C, antiseismic measures can be taken according to the guarding intensity; and for structures of Class D, antiseismic measures can be taken at one degree lower than the guarding intensity, but it should not be lowered when the guarding intensity is degree 6.
Note: (1) In this specification, “guarding intensity” is referred to as “intensity”; and intensity degree 6, degree 7, degree 8 and degree 9 is respectively referred to as “degree 6, degree 7, degree 8 and degree 9”.
(2) For the provision herein on taking antiseismic measures at one degree lower, it shall be made only once when there is a number of favorable factors.
1.0.7 This specification has been prepared in accordance with the current national standards “Unified standard on the reliability design of engineering structures” and “Basic terminologies and general signs for engineering structure design”.
1.0.8 The antiseismic design of structures shall also comply with the relevant national standards currently in force, in addition to implementing this specification.
