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Liquefaction Resistance of Geologically Aged Sand Deposits
David SaftnerUniversity of Minnesota Duluth
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
Photo from Penzien, 1964
Photo courtesy of Rebecca Teasley
dvo
vo rg
aCSR
'65.0 max
Whitman (1971)
Seed and Idriss (1971)
Updated several times since 1971
“Simplified” Method
0 20 40 60 80 100 120 140 160 1800
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Normalized Tip Resistance, qc1N
Cyc
lic R
esi
stan
ce R
atio
, C
RR
Robertson & Wride (1998)
Moss et al. (2006)
Idriss & Boulanger (2008)
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
10-2
100
102
104
106
108
1
1.5
2
2.5
3
3.5
Age (years)
Str
engt
h G
ain
Fac
tor
Kulhawy and Mayne (1990)
Seed (1979)
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)
𝐾𝐷𝑅=1.08𝑀𝐸𝑉𝑅−0.08
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
(from Hryciw, 1986)
20
0 5 10 15 20 25 30 35 400
CPT tip resistance, qc (MPa)
Pre-Blast Range (7 tests)
One Week Range (6 tests)2
4
6
8
10
12
14
16
18
Dep
th, z
(m
)
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
Blast site
Paleo-liquefactionsites
Photo courtesy of Mulzer Crushed Stone, Inc.
Griffin, IN
Nor
th
Clay
Loose ~GWTSand
DenseSand
LooseGravellySand
2m
1m
2m
5m
4mLower Liquefiable Layer
Upper Liquefiable Layer
0 m
2 m
4 m
6 m
8 m
10 m
12 m
14 m
Paleo-liquefaction feature
Paleo-liquefaction feature
6 8 10 12 14 16 1810
10.5
11
11.5
12
12.5
13
13.5
14
Tip resistance, qc (MPa)
Dep
th, z
(m
)
Pre-Blast Mean (7 tests)One Week Mean (6 tests)
200 210 220 230 240 250 26010
10.5
11
11.5
12
12.5
13
13.5
14
Shear Wave Velocity, Vs (m/sec)
Dep
th,
z (m
)
Pre-Blast V s
Post-Blast V s
Jebba Dam, Jebba, Nigeria
Explosive Compaction Projects in Aged Sand Deposits
Douglas Lake, Michigan
Harriet’s Bluff, Georgia
Greeley, Colorado
Pre-Blast Tip Resistance
(MPa)
Post-Blast Tip Resistance
(MPa)
Strength Gain
Factor
Geologic Age (years before
present)Griffin, IN 14.5 8 1.95 12,000Jebba, Nigeria (Mitchell and Solymar, 1984)
15 10 1.5 15,000
Harriet’s Bluff, GA (Hryciw and Dowding, 1988)
5 3.75 1.25 5,000
Greeley, CO (Charlie et al., 1992)
4.5 2.6 1.97 11,000
Douglas Lake, MI (Thomann and Hryciw, 1992)
8 2.5 2.15 9,000
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
Pre-Blast Vs
(m/sec)
Post-Blast Vs
(m/sec)
Predicted MEVR
Predicted MEVR
± 1 σ
Calculated MEVR
Griffin, IN 256 212 1.24 1.07 – 1.41 1.26Douglas Lake, MI (Thomann and Hryciw, 1992)
220 170 1.23 1.06 – 1.4 1.27
𝐾𝐷𝑅=0.201 log 𝑡+0.863
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
Explosive compaction resets a deposit’s
geotechnical age Determine age using Andrus et al. (2009)
MEVR approach Strength gain factor using:
Questions?
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