1 CENA H and V SITE AMPLIFICATION Walter Silva Pacific Engineering and Analysis October 1, 2009

2 NGA-E Horizontal Component - Conditional on V S (30m), is Amplification for WNA Similar to CENA Across Loading Levels?

3 Issues: Similarities in –Profiles Velocities –V S (30m) ≈ 180m/sec to 2,000m/sec –Basement V S »WNA ≈ 3,000 ft/sec »CENA ≈ 6,000 ft/sec »CENA Reference ≈ 9,300 ft/sec »Impact Shallow Profiles ≤ 500 ft »Impact Depth to 1 km/sec

4 Damping (kappa) –WNA, 0.04 sec, 5 Hz Peak Large Contribution of Bedrock ≈ 0.04 sec –Total kappa Varies Little With Soil Depth –CENA 0.04 SEC, 5 Hz peak Deep Profile > 3,000 ft Bedrock sec, 1,000 ft Soil 0.01 sec Large Impact on Shallow Profiles at Low Loading Levels

5 Nonlinear Dynamic Material Properties - WNA, Peninsular Range Curves - CENA Curves - Daniel Is, SC - Savannah River, G - Grand Gulf, M - Riverbend, M - ORNL, T - ?

6 Differences in Control Motion - Bedrock Kappa - WNA 0.04 sec, 5 Hz - CENA - Precambrian sec, 20 Hz - Sedimentary 0.02 to 0.04 sec, 10 Hz to 5 Hz - Relatively Higher Loading at High Frequency, Conditional on PGA

7 Site/Region Specific Hazard –≈ 35 NPP –≈ 100 projects –DOE Sites Savannah River ORNL Paducah

8 Project Areas –New Jersey, Virginia, Carolinas, Georgia, Tennessee, Indiana, Missouri, Oklahoma Project Regions –Central US, NYC, South Carolina Profiles Sampled –Soft to Firm Soil Overlying Hard and Soft Rock Soil Depths 20 ft to 10,000 ft –Soft to Firm Rock Several Hundred Feet to Thousands of Feet Over Hard Rock Profile Database –Several Hundred CENA Profiles

9 Available Analyses Suggest Deep Soil Response WNA ≈ CENA Across Loading Level - Relatively straightforward - Check/Confirm with Specific Cases Savannah River - Very Stiff Soil - Over Hard Rock (Crystalline) - Over Soft Rock (Dumbarton Basin)

10 Southern Coastal Plain - Charleston - Cooper Marl Piedmont - Residual Soil Saprolite Southern Miss Embayment Uplands, Grand Gulf - Till - Deep Stiff Soil Lowlands, Riverbend - Deep Soft Soil

11 Issues to Resolve –Shallow Soil < 3,000 ft Appropriate Total Kappa Constraint –Affects Low Loading Levels –Soft - Firm Rock Over Hard Rock ≤ 1 km Rock –Appropriate Profile –Appropriate kappa »Piedmont, Saprolite ≥ 1 km Rock –Characteristics of WNA Soft/Firm Rock

12 Data Requirements: –Relative Site Response –Kappa Inversions Shallow Soil (< 3,000 ft) Soft Rock –Shear-wave Velocities Recording Sites, at a Minimum V S (30m) Reference Site and Shallow Soil Sites – > V S to at Least 100m

13 Verticals –Hard Rock H only or H, V GMPEs Issues –Need CENA Relative Site Response For V –Empirical CENA H/V Ratios Small Magnitude/Large Distance –Rock: 1.1 at 1 Hz, 1.5 at 10 Hz –Soil 1.5 at 1 Hz, 1.7 at 5 Hz

14 Look at Close Distance V/H Ratios –WNA Hard Rock –CENA »Nahanni »Gazli »New Brunswick »Goodnow »Monticello »New Hampshire »Enola, Arkansas

15 –V Site Response Analysis Incident Inclined P-SV Nonlinear Constrained Modulus Uncoupled H and V Components? –NGAE Specifies H Hard Rock Only Develop Site Specific H Hazard Develop Site Specific Fully Probabilistic V Hazard –Distribution of V/H Ratios »Duke »Grand Gulf

16 Profile Comparison

17 –Site Response Analysis Incident Inclined P-SV Nonlinear Constrained Modulus Uncoupled H and V? –NGAE H Hard Rock Only Develop Site Specific H Hazard Develop Specific Fully Probabilistic V Hazard –Distribution V/H Ratios »Duke »Grand Gulf

18 Amplification M1P1

19 Amplification M1P1(Cont.)

20 Amplification

21 Amplification (Cont.)

22 Mean Centered NEHRP Profiles

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24 NEHRP Amplification Category C, WUS, CEUS

25 NEHRP Amplification Category D, WUS, CEUS

26 NEHRP Amplification Category E, WUS, CEUS

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29 Shear Wave Velocity Profiles

30 Shear Wave Velocity Profiles (cont.)

31 Profile Categories, Depth Bins, & Classes

32 Profile kappa values from small strain damping over maximum profile mean depth

33 Comparison of UHS

34 EPRI 28 Nuclear Plant Sites

35 PGA 6-Sigma Rock Hazards

36 Weight Summary

37 Historic and Instrumental Seismicity for the SEUS

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