1.0.1 This standard was formulated in order to implement "Construction Law of the People's Republic of China" and "Law of the People's Republic of China on Protecting Against and Mitigating Earthquake Disasters", carry out the policy of prevention first, relieve the earthquake damage and reduce loss, carry out appraisal for the seismic capability of available buildings and provide references for aseismic strengthening or for adopting other countermeasures for seismic protection and disaster reduction.
The available buildings meeting the requirements of this standard are with the corresponding seismic fortification targets within their expected continuous seismic working life: The available buildings with continuous seismic working life of 50 years are with the same fortification target as specified in the current national standard "Code for Seismic Design of Buildings" GB 50011; on meeting the same earthquake effect, the damaged condition of the available buildings with continuous seismic working life less than 50 years is a little larger than those appraised according to continuous seismic working life of 50 years. +
1.0.2 This standard is applicable to the seismic appraisal of such available buildings in the areas where the seismic fortification intensity is of Degree 6~9 but is not applicable to the evaluation on the seismic design and construction quality of newly-built construction engineering.
Generally, the seismic fortification intensity is adopted with the basic seismic intensity of the Seismic Ground Motion Parameter Zonation Map of China or the seismic fortification intensity specified in the current national standard "Code for Seismic Design of Buildings" GB 50011.
The antique buildings and the buildings with special industrial requirements shall be appraised according to special specifications.
Note: Thereinafter, the "seismic fortification intensity of Degree 6, Degree 7, Degree 8 and Degree 9" are referred to as " Degree 6, Degree 7, Degree 8 and Degree 9" for short in this standard.
1.0.3 The available buildings shall divided into four categories according to the current national standard "Standard for Classification of Seismic Protection of Building Constructions" GB 50223, the composite appraisal of seismic measures examination and seismic checking of these available buildings shall meet the following requirements:
1 Category C: Buildings of this category shall be checked for the seismic measures and be carried out with seismic checking according to the requirements of local fortification intensity.
2 Category B: With Degree 6~8, the buildings shall be examined for the seismic measures according to the requirements of one degree higher than the local fortification intensity; with Degree 9, the requirements shall be improved properly; the seismic checking shall be adopted according to the requirement of no less than the local fortification intensity.
3 Category A: Buildings of this category shall be examined for the seismic measures according to the requirement on no less than Category B through special study.
4 Category D: With Degree 7~9, the buildings shall be allowed being examined for the seismic measures according to the requirements of one degree lower than the local fortification intensity, the seismic checking shall allow properly reducing requirements based on the local fortification intensity; with Degree, buildings shall be disallowed doing seismic appraisal.
Note: The Category A, Category B, Category C and Category D in this standard respectively are the shortened forms of particular fortification category, major fortification category, standard fortification category and appropriate fortification category as specified in the current national standard "Standard for Classification of Seismic Protection of Building Constructions" GB 50223.
1.0.4 The continuous seismic working life of available buildings shall be selected based on the actual demand and possibility according to the following requirements:
1 As for the available buildings that are built in or before the 1970's and can be used continuously through durability appraisal, their continuous seismic working life shall not be less than 30 years; as for the available buildings built in the 1980's, the continuous seismic working life should be 40 years or much longer but shall not be less than 30 years.
2 As for the available buildings built in the 1990's (designed according to the aseismic design code implemented at that time), their continuous seismic working life should not be less than 40 years but shall be adopted with 50 years when conditions permit.
3 As for the available buildings built after 2001 (designed according to the aseismic design code implemented at that time), their continuous seismic working life should be 50 years.
1.0.5 The seismic appraisal methods for the available buildings of different continuous seismic working life shall meet the following requirements:
1 Buildings with continuous seismic working life of 30 years ("Category A buildings" for short) shall be adopted with the seismic appraisal methods for Category A buildings as specified in this chapter of this standard.
2 Buildings with continuous seismic working life of 40 years ("Category B buildings" for short) shall be adopted with the seismic appraisal methods for Category B buildings as specified in this chapter of this standard.
3 Buildings with continuous seismic working life of 50 years ("Category C buildings" for short) shall be carried out with seismic appraisal according to the requirements of the current national standard "Code for Seismic Design of Buildings" GB 50011.
1.0.6 The available buildings shall be carried out with seismic appraisal under the following conditions:
1 Buildings that are approximate to or exceed the design life but are required being used continuously.
2 Buildings, for which the original design does not consider improving the seismic fortification or seismic fortification requirement.
3 Buildings needing to change the purpose and environment for use of the structure.
4 Other buildings that are necessary to be carried out with seismic appraisal.
1.0.7 The seismic appraisal of available buildings shall not only meet the requirements of this standard, but also shall meet the relevant regulations specified in the current national standards and codes.
