geomechanics
MINOR PROJECT – SLOPE STABILITY DESIGN
Project Brief: You are required to design an embankment for a 30m wide roadway. The embankment needs to be designed
to meet the following specifications:
✓ 20kPa road traffic
✓ Flooding conditions
✓ Long term embankment
References: The embankment system can be designed using the following references:
✓ Borehole to establish the ground conditions (note at the groundwater is at the existing ground
surface)
✓ Software – SlopeW
Assessment: ✓ Determine the tallest embankment height for a batter slope of 4H:1V, 3H:1V and 2H:1V for the
following cases. Note that circular and non circular slips need to be assessed.
o short term stability assuming flooding conditions up to RL3m within the embankment, and
no flood water outside the embankment (target FoS >1.3)
o long term stability with no flooding conditions (target FoS >1.5)
✓ For an embankment height of 6m with 2H:1V batter, where should you place a row of piles to ensure
a long term FoS > 1.5 can be achieved? What characteristics will the piles need to have, including
shear capacity and length? The piles may comprise any material, e.g. concrete piles, steel sheets.
Deliverables: Short report summarising the assessment outcomes
AS Nil
1 4
-0 7
-1 7
TOPSOIL
QUATERNARY ALLUVIUM
TERTIARY BRIGHTON GROUP (RED BLUFF FORMATION)
U63
U63
CH
CH
MTOPSOIL: Silty CLAY; medium to high plasticity, grey, root matter.
Silty CLAY; high plasticity, dark grey.
0.5m Becoming grey
Silty CLAY; high plasticity, pale grey, yellow brown, with fine to coarse grained sand.
0.10
3.60
50
50 - 80
Borehole Information Field Material Description
VicRoads
Mordialloc Freeway
Braeside
2135645A
Hole Angle:
Bearing:
-90°
---
M E
T H
O D
1.86 m AHD
E 335155.034 N 5791500.89 MGA94 55
S U
P P
O R
T
W A
T E
R
B17-68173
This Borehole log should be read in conjunction with WSP's accompanying explanatory notes.
Date Commenced:
Date Completed:
Recorded By:
Log Checked By:
Drill Model/Mounting:
Borehole Diameter:
14-7-17
14-7-17
JL
NS
Surface RL:
Co-ords:
SHEET : 1 OF 6
Comacchio Geo 305/ Track
100 mm
Client:
Project:
Borehole Location:
Project Number:
BOREHOLE NO.
BOREHOLE ENGINEERING LOG W
S P
A u st
ra lia
P ty
L td
. V
0 0 8
.3 0 .0
0 2 P
B _ L IB
_ 7 .5
_ W
N _ N
E W
_ L O
G O
0 .G
L B
L o g
P B
N O
N -C
O R
E D
L O
G
S IT
E 2
6 -
M O
R D
IA L L O
C L
O G
S .G
P J
< <
D ra
w in
g F
ile >
>
2 9 -0
5 -2
0 1 8 1
2 :2
7 D
e ve
lo p e d b
y D
a tg
e l P
ty L
td
STRUCTURE AND ADDITIONAL
OBSERVATIONS
G R
A P
H IC
L O
G
F B
V L
L M D
D V D
V S
S F S T
V S
T HS
A M
P L
E RELATIVE DENSITY /
CONSISTENCY
U S
C S
S Y
M B
O L
F IE
L D
T E
S T
M O
IS T
U R
E
SOIL/ROCK MATERIAL FIELD DESCRIPTION
R L
( m
A H
D )
D E
P T
H (
m )
P O
C K
E T
P E
N E
T R
O M
E T
E R
(k P
a )
1.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
-2.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
W B C TERTIARY BRIGHTON GROUP (RED BLUFF FORMATION)
SPT
SPT
U63
CH
CI
SPT 2, 3, 5 N=8
SPT 3, 3, 5 N=8
MSilty CLAY; high plasticity, pale grey, yellow brown, with fine to coarse grained sand.
Sandy CLAY; medium plasticity, pale grey yellow brown, fine to coarse grained sand.
6.70
250
Borehole Information Field Material Description
VicRoads
Mordialloc Freeway
Braeside
2135645A
Hole Angle:
Bearing:
-90°
---
M E
T H
O D
1.86 m AHD
E 335155.034 N 5791500.89 MGA94 55
S U
P P
O R
T
W A
T E
R
B17-68173
This Borehole log should be read in conjunction with WSP's accompanying explanatory notes.
Date Commenced:
Date Completed:
Recorded By:
Log Checked By:
Drill Model/Mounting:
Borehole Diameter:
14-7-17
14-7-17
JL
NS
Surface RL:
Co-ords:
SHEET : 2 OF 6
Comacchio Geo 305/ Track
100 mm
Client:
Project:
Borehole Location:
Project Number:
BOREHOLE NO.
BOREHOLE ENGINEERING LOG W
S P
A u st
ra lia
P ty
L td
. V
0 0 8
.3 0 .0
0 2 P
B _ L IB
_ 7 .5
_ W
N _ N
E W
_ L O
G O
0 .G
L B
L o g
P B
N O
N -C
O R
E D
L O
G
S IT
E 2
6 -
M O
R D
IA L L O
C L
O G
S .G
P J
< <
D ra
w in
g F
ile >
>
2 9 -0
5 -2
0 1 8 1
2 :2
7 D
e ve
lo p e d b
y D
a tg
e l P
ty L
td
STRUCTURE AND ADDITIONAL
OBSERVATIONS
G R
A P
H IC
L O
G
F B
V L
L M D
D V D
V S
S F S T
V S
T HS
A M
P L
E RELATIVE DENSITY /
CONSISTENCY
U S
C S
S Y
M B
O L
F IE
L D
T E
S T
M O
IS T
U R
E
SOIL/ROCK MATERIAL FIELD DESCRIPTION
R L
( m
A H
D )
D E
P T
H (
m )
P O
C K
E T
P E
N E
T R
O M
E T
E R
(k P
a )
-2.5
-3.0
-3.5
-4.0
-4.5
-5.0
-5.5
-6.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
W B C TERTIARY BRIGHTON GROUP (RED BLUFF FORMATION)
SPT
SPT
SPT
CI
CH
SW
CI
SPT 4, 7, 11 N=18
SPT 4, 16,
10/40mm N=R
SPT 6, 9, 11 N=20
MSandy CLAY; medium plasticity, pale grey yellow brown, fine to coarse grained sand.
Silty CLAY; high plasticity, pale grey, yellow brown, trace sand.
SAND; fine to coarse grained, brown.
Sandy CLAY; medium plasticity, grey - pale grey, fine to medium grained sand.
8.30
9.50
11.50
Borehole Information Field Material Description
VicRoads
Mordialloc Freeway
Braeside
2135645A
Hole Angle:
Bearing:
-90°
---
M E
T H
O D
1.86 m AHD
E 335155.034 N 5791500.89 MGA94 55
S U
P P
O R
T
W A
T E
R
B17-68173
This Borehole log should be read in conjunction with WSP's accompanying explanatory notes.
Date Commenced:
Date Completed:
Recorded By:
Log Checked By:
Drill Model/Mounting:
Borehole Diameter:
14-7-17
14-7-17
JL
NS
Surface RL:
Co-ords:
SHEET : 3 OF 6
Comacchio Geo 305/ Track
100 mm
Client:
Project:
Borehole Location:
Project Number:
BOREHOLE NO.
BOREHOLE ENGINEERING LOG W
S P
A u st
ra lia
P ty
L td
. V
0 0 8
.3 0 .0
0 2 P
B _ L IB
_ 7 .5
_ W
N _ N
E W
_ L O
G O
0 .G
L B
L o g
P B
N O
N -C
O R
E D
L O
G
S IT
E 2
6 -
M O
R D
IA L L O
C L
O G
S .G
P J
< <
D ra
w in
g F
ile >
>
2 9 -0
5 -2
0 1 8 1
2 :2
7 D
e ve
lo p e d b
y D
a tg
e l P
ty L
td
STRUCTURE AND ADDITIONAL
OBSERVATIONS
G R
A P
H IC
L O
G
F B
V L
L M D
D V D
V S
S F S T
V S
T HS
A M
P L
E RELATIVE DENSITY /
CONSISTENCY
U S
C S
S Y
M B
O L
F IE
L D
T E
S T
M O
IS T
U R
E
SOIL/ROCK MATERIAL FIELD DESCRIPTION
R L
( m
A H
D )
D E
P T
H (
m )
P O
C K
E T
P E
N E
T R
O M
E T
E R
(k P
a )
-6.5
-7.0
-7.5
-8.0
-8.5
-9.0
-9.5
-10.0
8.5
9.0
9.5
10.0
10.5
11.0
11.5
W B C TERTIARY BRIGHTON GROUP (RED BLUFF FORMATION)
TERTIARY BRIGHTON GROUP (BEAUMARIS SANDSTONE)
SPT
SPT
SPT
CI
SW
CL
SPT 3, 4, 4 N=8
SPT 16,
10/40mm HB N=R
SPT 2, 3, 7 N=10
MSandy CLAY; medium plasticity, grey - pale grey, fine to medium grained sand.
SAND; fine to coarse grained, grey.
Silty sandy CLAY; low plasticity, pale brown - green, fine grained sand, with brown bands of fine grained sand
14.40
15.50
Borehole Information Field Material Description
VicRoads
Mordialloc Freeway
Braeside
2135645A
Hole Angle:
Bearing:
-90°
---
M E
T H
O D
1.86 m AHD
E 335155.034 N 5791500.89 MGA94 55
S U
P P
O R
T
W A
T E
R
B17-68173
This Borehole log should be read in conjunction with WSP's accompanying explanatory notes.
Date Commenced:
Date Completed:
Recorded By:
Log Checked By:
Drill Model/Mounting:
Borehole Diameter:
14-7-17
14-7-17
JL
NS
Surface RL:
Co-ords:
SHEET : 4 OF 6
Comacchio Geo 305/ Track
100 mm
Client:
Project:
Borehole Location:
Project Number:
BOREHOLE NO.
BOREHOLE ENGINEERING LOG W
S P
A u st
ra lia
P ty
L td
. V
0 0 8
.3 0 .0
0 2 P
B _ L IB
_ 7 .5
_ W
N _ N
E W
_ L O
G O
0 .G
L B
L o g
P B
N O
N -C
O R
E D
L O
G
S IT
E 2
6 -
M O
R D
IA L L O
C L
O G
S .G
P J
< <
D ra
w in
g F
ile >
>
2 9 -0
5 -2
0 1 8 1
2 :2
7 D
e ve
lo p e d b
y D
a tg
e l P
ty L
td
STRUCTURE AND ADDITIONAL
OBSERVATIONS
G R
A P
H IC
L O
G
F B
V L
L M D
D V D
V S
S F S T
V S
T HS
A M
P L
E RELATIVE DENSITY /
CONSISTENCY
U S
C S
S Y
M B
O L
F IE
L D
T E
S T
M O
IS T
U R
E
SOIL/ROCK MATERIAL FIELD DESCRIPTION
R L
( m
A H
D )
D E
P T
H (
m )
P O
C K
E T
P E
N E
T R
O M
E T
E R
(k P
a )
-10.5
-11.0
-11.5
-12.0
-12.5
-13.0
-13.5
-14.0
12.5
13.0
13.5
14.0
14.5
15.0
15.5
W B C TERTIARY BRIGHTON GROUP (BEAUMARIS SANDSTONE)
TERTIARY GELLIBRAND MARL (FORMERLY FYANSFORD FORMATION)
SPT
SPT
SPT
CL
SC
SPT 2, 3, 7 N=10
SPT 3, 6, 10 N=16
SPT 5, 7, 13 N=20
MSilty sandy CLAY; low plasticity, pale brown - green, fine grained sand, with brown bands of fine grained sand
Clayey SAND; fine grained, pale brown, low plasticity fines.
18.2m Becoming grey with dark green pockets.
17.30
Borehole Information Field Material Description
VicRoads
Mordialloc Freeway
Braeside
2135645A
Hole Angle:
Bearing:
-90°
---
M E
T H
O D
1.86 m AHD
E 335155.034 N 5791500.89 MGA94 55
S U
P P
O R
T
W A
T E
R
B17-68173
This Borehole log should be read in conjunction with WSP's accompanying explanatory notes.
Date Commenced:
Date Completed:
Recorded By:
Log Checked By:
Drill Model/Mounting:
Borehole Diameter:
14-7-17
14-7-17
JL
NS
Surface RL:
Co-ords:
SHEET : 5 OF 6
Comacchio Geo 305/ Track
100 mm
Client:
Project:
Borehole Location:
Project Number:
BOREHOLE NO.
BOREHOLE ENGINEERING LOG W
S P
A u st
ra lia
P ty
L td
. V
0 0 8
.3 0 .0
0 2 P
B _ L IB
_ 7 .5
_ W
N _ N
E W
_ L O
G O
0 .G
L B
L o g
P B
N O
N -C
O R
E D
L O
G
S IT
E 2
6 -
M O
R D
IA L L O
C L
O G
S .G
P J
< <
D ra
w in
g F
ile >
>
2 9 -0
5 -2
0 1 8 1
2 :2
7 D
e ve
lo p e d b
y D
a tg
e l P
ty L
td
STRUCTURE AND ADDITIONAL
OBSERVATIONS
G R
A P
H IC
L O
G
F B
V L
L M D
D V D
V S
S F S T
V S
T HS
A M
P L
E RELATIVE DENSITY /
CONSISTENCY
U S
C S
S Y
M B
O L
F IE
L D
T E
S T
M O
IS T
U R
E
SOIL/ROCK MATERIAL FIELD DESCRIPTION
R L
( m
A H
D )
D E
P T
H (
m )
P O
C K
E T
P E
N E
T R
O M
E T
E R
(k P
a )
-14.5
-15.0
-15.5
-16.0
-16.5
-17.0
-17.5
-18.0
16.5
17.0
17.5
18.0
18.5
19.0
19.5
W B C TERTIARY GELLIBRAND MARL (FORMERLY FYANSFORD FORMATION)
SPT
SC
SPT 3, 4, 9 N=13
MClayey SAND; fine grained, grey with dark green pockets, low plasticity fines.
END OF BOREHOLE AT 20.75 m Target depth achieved
20.00
Borehole Information Field Material Description
VicRoads
Mordialloc Freeway
Braeside
2135645A
Hole Angle:
Bearing:
-90°
---
M E
T H
O D
1.86 m AHD
E 335155.034 N 5791500.89 MGA94 55
S U
P P
O R
T
W A
T E
R
B17-68173
This Borehole log should be read in conjunction with WSP's accompanying explanatory notes.
Date Commenced:
Date Completed:
Recorded By:
Log Checked By:
Drill Model/Mounting:
Borehole Diameter:
14-7-17
14-7-17
JL
NS
Surface RL:
Co-ords:
SHEET : 6 OF 6
Comacchio Geo 305/ Track
100 mm
Client:
Project:
Borehole Location:
Project Number:
BOREHOLE NO.
BOREHOLE ENGINEERING LOG W
S P
A u st
ra lia
P ty
L td
. V
0 0 8
.3 0 .0
0 2 P
B _ L IB
_ 7 .5
_ W
N _ N
E W
_ L O
G O
0 .G
L B
L o g
P B
N O
N -C
O R
E D
L O
G
S IT
E 2
6 -
M O
R D
IA L L O
C L
O G
S .G
P J
< <
D ra
w in
g F
ile >
>
2 9 -0
5 -2
0 1 8 1
2 :2
7 D
e ve
lo p e d b
y D
a tg
e l P
ty L
td
STRUCTURE AND ADDITIONAL
OBSERVATIONS
G R
A P
H IC
L O
G
F B
V L
L M D
D V D
V S
S F S T
V S
T HS
A M
P L
E RELATIVE DENSITY /
CONSISTENCY
U S
C S
S Y
M B
O L
F IE
L D
T E
S T
M O
IS T
U R
E
SOIL/ROCK MATERIAL FIELD DESCRIPTION
R L
( m
A H
D )
D E
P T
H (
m )
P O
C K
E T
P E
N E
T R
O M
E T
E R
(k P
a )
-18.5
-19.0
-19.5
-20.0
-20.5
-21.0
-21.5
-22.0
20.5