Paleoseismic Investigations for Determining the Design Ground Motions for Nuclear Power Plants

Transcription

1 Paleoseismic Investigations for Determining the Design Ground Motions for Nuclear Power Plants Russell A. Green Department of Civil and Environmental Engineering Purdue Geotechnical Society Workshop May 7, 2007

2 Acknowledgements: Collaborators: Dr. Scott M. Olson, University of Illinois Dr. Stephen Obermeier, US Geological Survey, retired Ms. Kate Gunberg, PhD Student, University of Michigan Funding: US National Science Foundation

3 Renewed Interest in Nuclear Power in the US (January 2006)

4 Locations of Newly Proposed Nuclear Reactors? Active Tectonic Region Stable Continental Region 2?? ? 1 2 2? 2 5 1? 4 2? Information from Nuclear Energy Institute At least 26 new commercial nuclear reactors at least 16 different sites in at least 12 different states

5 Percent Cost of a Nuclear Plant vs. Earthquake Ground Acceleration 20 Percent of Plant Cost Safe Shutdown Earthquake pga (g) (Stevenson 2003)

6 Review of Earthquake Geology and Engineering Seismology

7 Geology of Earthquakes Earthquakes in Stable Continental Regions??? Poorly Defined

8 Geology of Earthquakes in Stable Continental Crust Johnston and Kanter (1990)

9 Geology of Earthquakes in Stable Continental Crust Johnston and Kanter (1990)

10 Reelfoot Rift

11 Seismicity of the Eastern United States:

12 Gutenberg-Richter Magnitude Recurrence Relationship (b-line) Adapted from Schwartz and Coppersmith (1984)

13 Paleoliquefaction Features -- Secondary Evidence

14 Review of Liquefaction Phenomenon GRAVITY LOAD U=U hs BEFORE LIQUEFACTION

15 Review of Liquefaction Phenomenon GRAVITY LOAD U=U hs +U xs = σ v DURING LIQUEFACTION

16 Review of Liquefaction Phenomenon U=U hs GRAVITY LOAD POST DENSIFICATION

17 Review of Liquefaction Phenomenon 0 (a) Fine-grained cap Resultant tensile stress direction and direction of crack propagation (b) 2 Depth (m) 4 Water flow during reconsolidation Sand 6 Static water pressure Liquefied water pressure Water pressure acts normal to surface of flaw Change in water pressure Water flow during reconsolidation Porewater pressure (kpa) Olson et al. (2007)

18 Review of Liquefaction Phenomenon Sand Boil (or Blow) Obermeier (1996)

19 Geologic Evidence of Earthquakes - Liquefaction 1964 Niigata, Japan (Steinbrugge Collection) Crater formation & Spreading of Sand at Ten-Mile Hill 1886 Charleston Earthquake (from Dutton 1889)

20 Review of Simplified Liquefaction Evaluation Procedure acc (g) time (sec) a max CSR M Liquefaction No Liquefaction CRR CSR = 0.65 M7.5 a max g σ V amplitude σ V ' o r d 1 MSF duration N 1,60cs

21 Review of Simplified Liquefaction Evaluation Procedure 4.5 MSF Proposed by Various Investigators MSF NCEER Recommended Range Seed and Idriss, (1982) Idriss Ambraseys (1988) Arango (1996) Arango (1996) Andrus and Stokoe Youd and Noble, PL<20% Youd and Noble, PL<32% Youd and Noble, PL<50% Earthquake Magnitude, M (NCEER 1997)

22 Review of Simplified Liquefaction Evaluation Procedure 0.60 Factor of Safety Against Liquefaction: Liquefaction CRR FS = CRR CSR M7.5 CSR M CSR M7.5 No Liquefaction 0.20 CRR N 1,60cs

23 Evidence of Large Paleoearthquakes in the Wabash Valley

24 (Obermeier 1998) Paleoliquefaction in the Wabash Valley

25 (Obermeier 1998) Paleoliquefaction in the Wabash Valley

26 (Obermeier 1998) Paleoliquefaction in the Wabash Valley

27 (Obermeier 1998) Paleoliquefaction in the Wabash Valley

28 Simplified Liquefaction Evaluation Procedure CRR 0.40 Liquefaction CSR M CSR M7.5 No Liquefaction FS CRR = CSR M CRR N 1,60cs

29 Back Analyses (simplified procedure) FS = CRR = 1 a = CSR max M7.5 CRR MSF g σ V ' o 0.65 σ V r d FS = 1 a max M combinations requisite to induce liquefaction: FS < 1 a max (g) a max M combinations 0.05 insufficient to induce liquefaction: FS > Magnitude

30 Back Analyses (simplified procedure) FS = CRR = 1 a = CSR max M7.5 CRR MSF g σ V ' o 0.65 σ V r d 0.25 a max (g) FS = 1 Lower Bound M credible a max M combinations Magnitude

31 Wabash Valley Seismic Zone Wabash R. Lafayette North Urbana PL Springfield Decatur Wabash R. Terre Haute NP TH 0.01 m Indianapolis BG St. Louis 0.15 m 0.3 m YO PA Bridgeport VW 0.5 m PB Eel R. WO RF SM Vincennes White R. HA E. Fk. White R. region of shallow bedrock Columbus Louisville Green et al. (2005) city or town river or stream surveyed river or stream contour of maximum dike width estimated energy center Ohio River MA Evansville Ohio River Paleoliquefaction Features Associated with the Vincennes Event re-analyzed as part of this study maximum dike width 0.5 m m m m < 0.05 m

32 Wabash Valley Seismic Zone Regional Integration of Data a max (g) M8 MA PB 6.0 VW RF PA SM YO YO Severity of Liq. marginal BG moderate WO TH NP severe high intermediate low PL PL FDQ South of Vincennes North of Vincennes R (km) Green et al. (2005)

33 New Madrid Seismic Zone Cramer (2001)

34 Summary The renewed interest in nuclear power will require the accurate quantification of the earthquake hazard. In the low-to-moderate seismic zones, paleoliquefaction studies have proven to be a valuable tool in determining the recurrence time of moderate-to-large earthquakes.

35 The End!!

36 References: Cramer, C.H. (2001). A Seismic Hazard Uncertainty Analysis for the New Madrid Seismic Zone, Engineering Geology, 62: Dutton, C.E. (1889). The Charleston Earthquake of August 31, 1886, USGS Ninth Annual Report , US Geological Survey, Washington, DC, Green, R.A., Olson, S.M., and Obermeier, S.F. (2005). "Engineering Geologic and Geotechnical Analysis of Paleoseismic Shaking Using Liquefaction Effects: Field Examples," Engineering Geology, 76: Johnston, A.C. and Kanter, L.R. (1990). Earthquakes in Stable Continental Crust, Scientific American, 262(3): NCEER (1997). Proceeding of the NCEER Workshop on Evaluation of Liquefaction Resistance of Soils, (T.L. Youd and I.M. Idriss, eds.), Technical Report NCEER , National Center for Earthquake Engineering Research, State University of New York at Buffalo, 276pp. Obermeier, S.F. (1996). Use of Liquefaction-Induced Features for Paleoseismic Analysis An Overview of How Seismic Liquefaction Features can be Distinguished from Other Features and How Their Regional Distribution and Properties of Source Sediment can be Used to Infer the Location and Strength of Holocene Paleo-Earthquakes, Engineering Geology, 44:1-76. Obermeier, S.F. (1998). Seismic Liquefaction Features: Examples from Paleoseismic Investigations in the Continental United States, USGS Open-file Report , US Geological Survey, Reston, VA, Olson, S.M., Obermeier, S.F., Pogue, K.R., and Green, R.A. (2007). Origin of the Clastic Dikes in Missoula Flood Sediments and Potential Impacts on Hazard Analysis, Engineering Geology (in review).

37 Reiter, L. (1990). Earthquake Hazard Analysis, Issues and Insights, Columbia University Press, NY. Schwartz, D.P. and Coppersmith, K.J. (1984). "Fault Behavior and Characteristic Earthquakes: Examples from the Wasatch and San Andreas Faults," Journal of Geophysical Research, 89: Stevenson, J.D. (2003). Historical Development of the Seismic Requirements for Construction of Nuclear Power Plants in the U.S. and Worldwide and their Current Impact on Cost and Safety, Transactions of the 17 th Intern. Conf. on Structural Mechanics in Reactor Technology (SMiRT 17), Paper #A01 Steinbrugge Collection: