David Saftner "Liquefcation Aged Sand Deposits"

Report
Liquefaction Resistance of
Geologically Aged Sand Deposits
David Saftner
University of Minnesota Duluth
Outline



Liquefaction Overview
Current Methods of Accounting for Age
in Liquefaction Analysis
Additional Data from Explosive
Compaction Projects

Griffin, Indiana

Comparison of Current Methods

Conclusions
Photo from Penzien, 1964
Photo courtesy of Rebecca Teasley
“Simplified” Method

Whitman (1971)

Seed and Idriss (1971)

Updated several times since 1971
 amax   vo 
rd

CSR  0.65
 g   'vo 
0.5
0.45
Robertson & Wride (1998)
Cyclic Resistance Ratio, CRR
0.4
Moss et al. (2006)
Idriss & Boulanger (2008)
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
0
20
40
60
80
100
120
Normalized Tip Resistance, qc1N
140
160
180
Outline



Liquefaction Overview
Current Methods of Accounting for Age
in Liquefaction Analysis
Additional Data from Explosive
Compaction Projects

Griffin, Indiana

Comparison of Current Methods

Conclusions
3.5
Kulhawy and Mayne (1990)
Seed (1979)
Strength Gain Factor
3
2.5
2
1.5
1
-2
10
0
10
2
10
Age (years)
4
10
6
10
8
10
Photo from USGS, 2009
Photo from USGS, 2009
Photo from South Carolinian Library Archives, 2012
From Andrus et al., 2009
Measured to Estimated Shear Wave Velocity Ratio
(Hayati and Andrus, 2009)
 = 1.08 − 0.08
Outline



Liquefaction Overview
Current Methods of Accounting for Age
in Liquefaction Analysis
Additional Data from Explosive
Compaction Projects

Griffin, Indiana

Comparison of Current Methods

Conclusions
(from Hryciw, 1986)
CPT tip resistance, qc (MPa)
0
0
5
10
15
20
25
30
35
Pre-Blast Range (7 tests)
One Week Range (6 tests)
2
4
Depth, z (m)
6
8
10
12
14
16
18
20
40
Outline



Liquefaction Overview
Current Methods of Accounting for Age
in Liquefaction Analysis
Additional Data from Explosive
Compaction Projects

Griffin, Indiana

Comparison of Current Methods

Conclusions
Griffin,
Paleo-liquefaction
IN
sites
Blast site
Photo courtesy of Mulzer Crushed Stone, Inc.
0m
Clay
2m
2m
Loose
Sand
4m
~GWT
Upper
Liquefiable
Layer
1m
2m
6m
5m
8m
10 m
12 m
14 m
Dense
Sand
Loose
Gravelly
Sand
Lower
Liquefiable
Layer
4m
Paleo-liquefaction feature
Paleo-liquefaction feature
Tip resistance, qc (MPa)
10
10.5
Depth, z (m)
11
11.5
12
12.5
13
13.5
14
6
8
10
12
14
Pre-Blast Mean (7 tests)
One Week Mean (6 tests)
16
18
Shear Wave Velocity, Vs (m/sec)
200
10
210
220
230
Pre-Blast V s
10.5
11
Depth, z (m)
11.5
12
12.5
13
13.5
14
Post-Blast V s
240
250
260
Explosive Compaction Projects in
Aged Sand Deposits

Jebba Dam, Jebba, Nigeria

Douglas Lake, Michigan

Harriet’s Bluff, Georgia

Greeley, Colorado
Griffin, IN
Jebba, Nigeria
(Mitchell and
Solymar, 1984)
Harriet’s Bluff, GA
(Hryciw and
Dowding, 1988)
Greeley, CO
(Charlie et al., 1992)
Douglas Lake, MI
(Thomann and
Hryciw, 1992)
Pre-Blast Tip
Resistance
(MPa)
14.5
15
Post-Blast Tip
Resistance
(MPa)
8
10
Strength
Gain
Factor
1.95
1.5
Geologic Age
(years before
present)
12,000
15,000
5
3.75
1.25
5,000
4.5
2.6
1.97
11,000
8
2.5
2.15
9,000
Outline



Liquefaction Overview
Current Methods of Accounting for Age
in Liquefaction Analysis
Additional Data from Explosive
Compaction Projects

Griffin, Indiana

Comparison of Current Methods

Conclusions
Griffin, IN
Douglas Lake, MI
(Thomann and
Hryciw, 1992)
PreBlast Vs
(m/sec)
256
220
PostBlast Vs
(m/sec)
212
170
Predicted
MEVR
1.24
1.23
Predicted
MEVR
±1σ
1.07 – 1.41
1.06 – 1.4
Calculated
MEVR
1.26
1.27
 = 0.201 log  + 0.863
Outline



Liquefaction Overview
Current Methods of Accounting for Age
in Liquefaction Analysis
Additional Data from Explosive
Compaction Projects

Griffin, Indiana

Comparison of Current Methods

Conclusions

Explosive compaction resets a deposit’s
geotechnical age
Determine age using Andrus et al. (2009)

MEVR approach
Strength gain factor using:

 = 0.201 log  + 0.863
Questions?

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