Presentation is loading. Please wait.

Presentation is loading. Please wait.

Liquefaction Resistance of Geologically Aged Sand Deposits David Saftner University of Minnesota Duluth.

Similar presentations


Presentation on theme: "Liquefaction Resistance of Geologically Aged Sand Deposits David Saftner University of Minnesota Duluth."— Presentation transcript:

1 Liquefaction Resistance of Geologically Aged Sand Deposits David Saftner University of Minnesota Duluth

2  Liquefaction Overview  Current Methods of Accounting for Age in Liquefaction Analysis  Additional Data from Explosive Compaction Projects  Griffin, Indiana  Comparison of Current Methods  Conclusions Outline

3 Photo from Penzien, 1964

4 Photo courtesy of Rebecca Teasley

5  Whitman (1971)  Seed and Idriss (1971)  Updated several times since 1971 “Simplified” Method

6 020406080100120140160180 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 Normalized Tip Resistance, q c1N Cyclic Resistance Ratio, CRR Robertson & Wride (1998) Moss et al. (2006) Idriss & Boulanger (2008)

7  Liquefaction Overview  Current Methods of Accounting for Age in Liquefaction Analysis  Additional Data from Explosive Compaction Projects  Griffin, Indiana  Comparison of Current Methods  Conclusions Outline

8

9 Photo from USGS, 2009

10

11 Photo from South Carolinian Library Archives, 2012

12 From Andrus et al., 2009

13 Measured to Estimated Shear Wave Velocity Ratio (Hayati and Andrus, 2009)

14

15  Liquefaction Overview  Current Methods of Accounting for Age in Liquefaction Analysis  Additional Data from Explosive Compaction Projects  Griffin, Indiana  Comparison of Current Methods  Conclusions Outline

16 (from Hryciw, 1986)

17 20 0510152025303540 0 CPT tip resistance, q c (MPa) Pre-Blast Range (7 tests) One Week Range (6 tests) 2 4 6 8 10 12 14 16 18 Depth, z (m)

18  Liquefaction Overview  Current Methods of Accounting for Age in Liquefaction Analysis  Additional Data from Explosive Compaction Projects  Griffin, Indiana  Comparison of Current Methods  Conclusions Outline

19 Blast site Paleo-liquefaction sites Photo courtesy of Mulzer Crushed Stone, Inc. Griffin, IN North

20 Clay Loose ~GWT Sand Dense Sand Loose Gravelly Sand 2m 1m 2m 5m 4m Lower Liquefiable Layer Upper Liquefiable Layer 0 m 2 m 4 m 6 m 8 m 10 m 12 m 14 m

21 Paleo-liquefaction feature

22

23

24

25 681012141618 10 10.5 11 11.5 12 12.5 13 13.5 14 Tip resistance, q c (MPa) Depth, z (m) Pre-Blast Mean (7 tests) One Week Mean (6 tests)

26 200210220230240250260 10 10.5 11 11.5 12 12.5 13 13.5 14 Shear Wave Velocity, V s (m/sec) Depth, z (m) Pre-Blast V s Post-Blast V s

27  Jebba Dam, Jebba, Nigeria Explosive Compaction Projects in Aged Sand Deposits  Douglas Lake, Michigan  Harriet’s Bluff, Georgia  Greeley, Colorado

28 Pre-Blast Tip Resistance (MPa) Post-Blast Tip Resistance (MPa) Strength Gain Factor Geologic Age (years before present) Griffin, IN14.581.9512,000 Jebba, Nigeria (Mitchell and Solymar, 1984) 15101.515,000 Harriet’s Bluff, GA (Hryciw and Dowding, 1988) 53.751.255,000 Greeley, CO (Charlie et al., 1992) 4.52.61.9711,000 Douglas Lake, MI (Thomann and Hryciw, 1992) 82.52.159,000

29  Liquefaction Overview  Current Methods of Accounting for Age in Liquefaction Analysis  Additional Data from Explosive Compaction Projects  Griffin, Indiana  Comparison of Current Methods  Conclusions Outline

30 Pre- Blast V s (m/sec) Post- Blast V s (m/sec) Predicted MEVR ± 1 σ Calculated MEVR Griffin, IN2562121.241.07 – 1.41 1.26 Douglas Lake, MI (Thomann and Hryciw, 1992) 2201701.231.06 – 1.41.27

31

32

33  Liquefaction Overview  Current Methods of Accounting for Age in Liquefaction Analysis  Additional Data from Explosive Compaction Projects  Griffin, Indiana  Comparison of Current Methods  Conclusions Outline

34

35 Questions?

36 GRAVITY LOAD U=U hs BEFORE LIQUEFACTIONINITIAL LIQUEFACTION U=U hs +U xs =  v

37 GRAVITY LOAD U=U hs POST LIQUEFACTION

38 LOOSE SATURATED SAND


Download ppt "Liquefaction Resistance of Geologically Aged Sand Deposits David Saftner University of Minnesota Duluth."

Similar presentations


Ads by Google