1.0.1 This specification is formulated according to "Law of the People's Republic of China on Protecting Against and Mitigating Earthquake Disasters" with view to implementing the guideline of prevention-based seismic protection and disaster reduction operation, relieving the seismic damage of highway engineering structure, ensuring people's life and property safety and reducing the economic losses.
1.0.2 This specification is applicable to seismic design of various classes of highways and structures.
1.0.3 Highway engineering structure shall be subjected to seismic design. The highway engineering structure, in case special seismic safety evaluation is not required for the engineering site, shall be subject to seismic fortification according to the ground motion parameter specified in “Seismic Ground Motion Parameter Zonation Map of China” (GB 18306). In the area where ground motion peak acceleration is greater than or equal to 0.40g, special study shall be carried out for the seismic design of highway engineering structure.
1.0.4 The site of independent oversized bridge engineering and independent super-long tunnel engineering and seismic risk site of expressway and Class I highway with ground motion peak acceleration larger than or equal to 0.40g shall be subject to seismic safety evaluation.
1.0.5 For the area with ground motion peak acceleration larger than or equal to 0.20g, highway engineering structures having important effect on the earthquake relief, economy and national defense or those difficult to be restored after damage may be determine as lifeline engineering. Seismic fortification criterion of lifeline engineering may be improved properly after approved by the state.
1.0.6 Mature and reliable new technology, material, equipment and process shall be adopted for the seismic design of highway engineering structure.
1.0.7 Seismic design of highway engineering structure shall not only meet those specified in this specification, but also meet those specified in the current relevant national and professional standards.
2 Terms and Symbols
2.1 Terms
2.1.1 Seismic fortification criterion
A benchmark for seismic fortification requirements, which is determined according to the ground motion parameter and the importance of use function of highway engineering structure.
2.1.2 Design basic acceleration of ground motion
Peak acceleration of ground motion with exceedance probability of 10% in 50 years, it also refers to the ground motion peak acceleration with recurrence interval of 475 years.
2.1.3 Earthquake action
Seismic motion on the structure, including horizontal earthquake action and vertical earthquake action.
2.1.4 E1 earthquake action
Earthquake action with recurrence interval of 475 years.
2.1.5 E2 earthquake action
Earthquake action with recurrence interval of 2000 years.
2.1.6 Seismic effect
A generic term for effects like structural internal force and deformation caused by earthquake action.
2.1.7 Characteristic period
Period value corresponding to the initial point of descending branch on acceleration response spectrum curve used for seismic design, which depends on earthquake environment and site category.
2.1.8 Seismic favorable site
