1.0.1 This guideline was established with a view to implementing "Law of the People's Republic of China on Protecting Against and Mitigating Earthquake Disasters", adopting the policy of prevention first, alleviating the earthquake damages on highway bridges, protecting people's life and property safety, decreasing economic losses and better exerting the functions of the highway traffic network and its actions in the seismic relief.
1.0.2 This guideline is mainly applicable to concrete beam bridges, masonry or concrete arch bridges whose single span is no more than 150m. As for the cable stayed bridges, suspension bridges and oversize span beam bridges and arch bridges whose single span exceeds 150m, they may be designed referring to the seismic design criteria given in this guideline.
1.0.3 According to the significance of highway bridges and difficulty of restoration (emergency repair) in this guideline, the seismic fortifications for bridges are classified into four classes, namely, class A, class B, class C and class D, respectively corresponding to different seismic fortification criterions and fortification targets.
1.0.4 As for highway bridges in areas where the seismic fortification intensity is magnitude 6 and above, seismic design must be carried out for them.
1.0.5 This guideline is applicable to the seismic design of highway bridges in areas where the seismic fortification intensity is magnitude 6, 7, 8 and 9. As for bridges in areas where the seismic fortification intensity is larger than magnitude 9 and large-span or special bridges with special requirements, their seismic design shall be studied specially and conducted according to the relevant specific requirements.
1.0.6 The seismic fortification intensity must be determined according to those documents (drawings) approved and issued by the national due authorities. As a rule, the seismic fortification intensity may be adopted in accordance with the basic seismic intensity specified in the current "Seismic Ground Motion Parameter Zonation Map of China". As for those bridges whose sites have already been conducted with special seismic safety evaluation, their seismic fortification shall be carried out according to the approved seismic fortification intensity or design seismic ground motion parameters.
1.0.7 As for the seismic design of highway bridges, except for the requirements in this guideline, those in the relevant national and professional standards and codes also shall be complied with.
