Seismic Design and Evaluation of Structures, Systems, and Components

DOE-STD-1020-2002

International Building Code 2000

ASCE 7-98

The seismic provisions in the Uniform Building Code (UBC) 1997 have not been found

to be equivalent to the 1997 NEHRP provisions. However, this code may be used on case by

case basis as long as the intent of the seismic provisions in this standard are met (Based on IBC

2000/1997 NEHRP provisions). The seismic design maps associated with 1997 UBC are

generally out of date (over 20 years old) and at a minimum the MCE ground motion maps in IBC

2000 should be consulted to ensure that DBE ground motion are adequate and conservative.

Other model building codes may be followed provided site-specific ground motion data is

incorporated into the development of the earthquake loading in a manner consistent with DOE-

STD-1023, and the NEHRP provisions.

For PC-3 and PC-4 SSCs, these seismic design and evaluation criteria specify that

seismic evaluation be accomplished by dynamic analysis. The recommended approach is to

perform an elastic response spectrum dynamic analysis to evaluate the elastic seismic demand on

SSCs. Inelastic energy absorption capability is allowed by permitting limited inelastic behavior.

By these provisions, the inelastic energy absorption capacity of structures is accounted for by the

parameter, F. However, strength and ductile detailing for the entire load path should be

assured. Elastically computed seismic response is reduced by F values ranging from 1 to 3 as a

means of accounting for inelastic energy absorption capability. The same F values are

specified for both Performance Categories of 3 and 4. In order to achieve the conservatism

appropriate for the different Performance Categories, the reduced seismic forces are multiplied

by a scale factor. Scale factors are specified for Performance Category 3 and 4. The resulting

factored seismic forces are combined with non-seismic concurrent loads and then compared to

code ultimate response limits. Alternatively for PC-3 and PC-4 SSCs, non-linear static (push-

over analysis) may be adequate, and in extreme cases a non-linear dynamic analysis may be

used, if justified. F factors should not be used when performing non linear analysis. For

concrete structures, the design detailing provisions from the ACI 349 which provide ductility,

toughness, and redundancy, are also required such that SSCs can fully achieve potential inelastic

energy absorption capability (for other materials, follow relevant codes listed in Chapter 1).

Also, explicit consideration of relative seismic anchor motion (SAM) effects is required for PC-

3 and PC-4 SSCs.

The overall DOE Seismic Design and Evaluation Procedure is shown in Figure 2-3. In

addition to the general provisions described in this chapter, the topics discussed in Appendix C

should be considered before commencing design or evaluation.

2.3 Seismic Design and Evaluation of Structures, Systems, and

Components

Select Performance Categories of structure, system, or component based on DOE

G 420.1-2 (Ref. 1-2) and DOE-STD-1021 (Ref. 1-10).

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