5 Deltaic 3 - MIT OpenCourseWare · 2.5 3.0 3.5 e o c c k = 0.5 e o k c k = 1/3 e o c k = de / d...
Transcript of 5 Deltaic 3 - MIT OpenCourseWare · 2.5 3.0 3.5 e o c c k = 0.5 e o k c k = 1/3 e o c k = de / d...
2 22.3
2.1
1.9
1.7
1.5
Permeability k, m/s log k (m/s)
1.3
2 23 34 45 56 67 78 89 91.1
101
10-10 10-9 10-8
102 1033 34 45
e - lg k
5 6 7 8 96 7 8 9
vσ' ,kPa log σ'vc (kPa)
1g = log10
e - lg σv̀
σv̀o
σp̀
The e vs. lg σv̀ and e vs. lg k relationships from a typical OEDK test on Louiseville clay.
Voi
d Ra
tio, α
1.75
1.50
1.25
1.00
0.75
0.50
0.25
00 0.5 1.0 1.5 2.0
Relation between the permeability change index Ck and eo for all clays tested.Adapted from Tavenas et al. (1983). "The Permeability of Natural Salt Clays: Parts I & II." CGJ 20(4), 629-668
2.5 3.0 3.5eo
ck = 0.5 eoc k
ck = 1/3 eo
ck = de / d log k eo~~ 12
13
-( )
Champlain claysOther Canadian claysOther clays
rk = 1.5
Deltaic
rk = 1
Atchafalaya
Comparison of vertical and horizontal permeabilities in intact natural clays.
For marine clays (mostly Canada) Typical rk= kh/kv = 1.0 - 1.5
10-8
10-9
10-10
10-9 10-8
10-8
10-7
10-6
10-10
987654
3
2
98765
4
3
2
2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9
Kho,
cm/se
c
m/s
Kvo
,m/s
kv = 10 cm/secx5 10-8+
Champlain claysOther Canadian claysOther claysφ 50 mm triaxial tests
10-4
10-5
10-6
10-7
10-8
10-910
120
110
S = 100%
100
9010 15 20 2515
Molding Water Content (%) Molding Water Content (%)
Con
duct
ivity
(cm
/s)
(for
S =
100
%)
Dry
Uni
t Wei
ght (
pcf)
Vicksburg Silty Clay: WL = 37, WP = 23 & IP = 14
2520
WoptHigh Effort
High
Medium
Low Compactive Effort
Kneading Compection
Data from Mitchell et al. ASCE, JSMFD 91(4). (1965) for Silty Clay Compacted with Impact Compaction: (a) Hydraulic Conductivity versus Molding Water Content; (b) Compection Curve (1 pct = 0.157 kN/m3)
Adapted from Daniel & Benson (1990), ASCE JGE 116(12)
Medium
Low
a b