EP 1110-2-12
30 Sep 95
Table 5-2
Peak Ground Accelerations (PGA's) for Use in Scaling the Standard Design Response
Spectra
PGA
Operating Basis
Maximum Credible
Seismic Zone
Earthquake (OBE)
Earthquake (MCE)
0
0.030
0.130
1
0.050
0.210
2A
0.095
0.360
2B
0.115
0.430
3
0.210
0.550
4
0.270
0.610
NOTES:
1. Refer to Figure 5-1 for the seismic zone maps.
2. PGA's are expressed as the decimal ratio of the acceleration due to gravity (g).
3. PGA's are obtained from curves of "Annual Risk of Exceedance vs. PGA" in Figure C1-7 of ATC-3 Tentative Provisions,
April 1984.
4. The PGA for the OBE is based on a 50 percent chance of exceedance in 100 years.
5. The MCE is considered to be the event with a 5,000-year return period (annual risk of exceedance = 0.0002
chance/year).
Figure 5-3. Ratio of PGA for the horizontal component to the PGA for the vertical component as a function
of source to site distance (R) and the fundamental period of vibration of the structure
5-7
Previous Page
