Figure 2-1. DOE-STD-1020 Combines Probabilistic and Deterministic Methods

DOE-STD-1020-2002

Deterministic Procedure

Meet Performance

Based on Industry Codes

Goal (consistent with

and Standards

DOE Safety Policy)

Detailing

Requirements

Probabilistic

Bas is

Permissible

(with historic check)

Response

Level

Response

Evaluation

Select

Load

Re asonable Le vel

Conservatism Added

of Haz ard

Figure 2-1. DOE-STD-1020 Combines Probabilistic and Deterministic Methods to

Achieve Performance Goals

Criteria are provided for each of the four Performance Categories 1 to 4 as defined in

DOE O 420.1, the accompanying Guide DOE G 420.1-2 (Ref. 1-2 ) and DOE-STD-1021 (Ref. 1-

10). The criteria for Performance Categories 1 and 2 are similar to those from model building

codes. Criteria for PC-3 are similar to those for Department of Defense Essential Facilities

(Ref. C-5) Tri-Services Manual. Criteria for PC-4 approach the provisions for commercial

nuclear power plants.

Seismic loading is defined in terms of a site-specific design response spectrum (the

Design/Evaluation Basis Earthquake, [DBE]). Either a site-specific design response spectrum

developed for the site, or a generic design response spectrum that is appropriate or conservative

for the site may be used. Seismic hazard estimates are used to establish the DBE per DOE-STD-

1023 (REF. 2-22).

For each Performance Category, a mean annual exceedance probability for the DBE, PH

is specified from which the maximum ground acceleration (and/or velocity) may be determined

from probabilistic seismic hazard curves, see Table 2-1. Evaluating maximum ground

acceleration from a specified mean annual probability of exceedance is illustrated in Figure 2-2a.

Earthquake input excitation to be used for design and evaluation by these provisions is defined

by a median amplification smoothed and broadened design/evaluation response spectrum shape

such as that shown in Figure 2-2b (from Ref. 2-2). Such spectra are determined in accordance

with DOE-STD-1023 (Ref. 2-19).

2-2