Using a performance-based earthquake engineering (PBEE) approach to estimate structural performance targets for bridges - Seismic Risk Analysis and Management of Civil Infrastructure Systems - page 541

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0

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-2

-3

0.1 1 10 100

Scale factor

20.4 Distribution of Type 2-EDP (in natural log units) vs. scale factor
for the one-scale-factor case.

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Scale factor

20.5 Distribution of Type 2-EDP (in natural log units) vs. scale factor
for the separate-scale-factor case.

The scatter of the EDP in Fig. 20.4 indicates that there is large variability
in the response for the records that have similar scale factors. Therefore,
even if the scale factor for a record is near unity, that record may not give
a good estimate of the average response. The variability of response is not
sensitive to the scaling of the records, since the amount of scatter in the
EDP does not change with the scale factor. By using separate scale factors