The Standard considers loads on structures due to earthquake ground motion. The provisions are not intended to prevent damage due to surface rupture, landslip or liquefaction. Nor do they consider other secondary earthquake effects such as fire, loss of services, seiche or tsunami. They do not consider site-structure resonance, where the natural frequency of a site is the same as that of the structure. They do not consider pounding of adjacent structures moving out of phase in an earthquake. These aspects require consideration of issues other than 'loads' and therefore are inappropriate in a loading Standard.
Special structures require special consideration of their response characteristics and environment that is beyond the scope of these provisions. Special structures such as nuclear reactors and cyrogenic tanks, which may present a considerable hazard to the community in the event of their failure, are not covered by the Standard, nor are industrial facilities of high economic importance. In either event, such structures require consideration of strong earthquake motions of very low probability, regardless of location. Structures with unusual structural characteristics, or of novel design or construction, are not excluded by the Standard. However, the Standard may be of little assistance in the design of such structures since a structural response factor (Rf) may not have been assigned.
Bridges are not covered by the Standard but could be included with some additional requirements.
Agricultural buildings may be excluded from earthquake consideration because of the exceptionally low risk to life involved.
Alterations to existing structures are covered by these provisions (see Section 8) but the assessment, strengthening and repairs to existing structures are not covered. However, guidance and some information are included in Appendix E..