anchorages and retaining structures
TRANSCRIPT
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Brussels, 18-20 February 2008 – Dissemination of information workshop 1
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997-1 Eurocode 7
Section 8 – Anchorages
Section 9 – Retaining structures
Brian Simpson Arup Geotechnics
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2 ©
EN 1997-1Geotechnical design – General Rules BP106.9
BP111.5 BP112.6 BP124-T1.311 General
2 Basis of geotechnical design
3 Geotechnical data
4 Supervision of construction, monitoring and maintenance
5 Fill, dewatering, ground improvement and reinforcement
6 Spread foundations
7 Pile foundations8 Anchorages
9 Retaining structures
10 Hydraulic failure
11 Overall stability12 Embankments
Appendices A to J
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8 AnchoragesBP124-F3.6
8.1 General
8.2 Limit states
8.3 Design situations and actions
8.4 Design and construction considerations
8.5 Ultimate limit state design8.6 Serviceability limit state design
8.7 Suitability tests
8.8 Acceptance tests
8.9 Supervision and monitoring
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8 Anchorages
• Section depends on EN1537 - Execution of special
geotechnical work - Ground anchors
• Not fully compatible with EN1537. Further work on
this is underway.
• BS8081 being retained for the time being.
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EN1537:1999
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EN1537:1999Execution of special geotechnical work - Ground anchors
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EN1537:1999 Execution of special geotechnical work - Ground anchors
- provides details of test procedures (creep load etc)
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Partial factors in anchor design
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Brussels, 18-20 February 2008 – Dissemination of information workshop 16
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997-1 Eurocode 7
Section 8 – Anchorages
Section 9 – Retaining structures
Brian Simpson Arup Geotechnics
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Brussels, 18-20 February 2008 – Dissemination of information workshop 17
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997-1 Eurocode 7
Section 9 – Retaining structures
Fundamentals – Design Approaches
Main points in the code text
Examples:Comparisons with previous (UK) practice
Comparison between Design Approaches
Lessons from the Dublin Workshop
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Brussels, 18-20 February 2008 – Dissemination of information workshop 18
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997-1 Eurocode 7
Section 9 – Retaining structures
Fundamentals – Design Approaches
Main points in the code text
Examples:Comparisons with previous (UK) practice
Comparison between Design Approaches
Lessons from the Dublin Workshop
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Genting Highlands BP87.59 BP106.30 BP111.22 BP112.43 BP119.43 BP124-F3.9 BP130.33 BP145a.8
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Genting Highlands BP87.60 BP106.31 BP111.23 BP112.44 BP119.44 BP124-F3.10 BP130.34 BP145a.9
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FOS > 1 for characteristic soil strengthsBP87.61 BP106.32 BP111.24 BP112.45
BP119.45 BP124-F3.11 BP130.35 BP145a.10
- but not big enough
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The slope and retaining wall are all part of the same
problem. BP87.62 BP106.33 BP111.25 BP112.46
BP119.46 BP124-F3.12 BP130.36 BP145a.11
Structure and soil must be designedtogether - consistently.
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Approaches to ULS design –
The merits ofDesign Approach 1 in Eurocode 7Brian Simpson
Arup Geotechnics BP145a.1
ISGSR2007 - First International Symposium on
Geotechnical Safety and Risk
EUROCODES EN1997 1: Anchorages and Retaining structures
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Brussels, 18-20 February 2008 – Dissemination of information workshop 24
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997-1 Eurocode 7
Section 9 – Retaining structuresFundamentals – Design Approaches
Main points in the code text
Examples:Comparisons with previous (UK) practice
Comparison between Design Approaches
Lessons from the Dublin Workshop
EN 1997-1
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EN 1997-1Geotechnical design – General Rules BP106.9 BP111.5 BP112.6 BP124-T
1 General
2 Basis of geotechnical design
3 Geotechnical data
4 Supervision of construction, monitoring and maintenance5 Fill, dewatering, ground improvement and reinforcement
6 Spread foundations
7 Pile foundations
8 Anchorages9 Retaining structures
10 Hydraulic failure
11 Overall stability
12 Embankments
Appendices A to J
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9 Retaining structures
9.1 General
9.2 Limit states
9.3 Actions, geometrical data and design situations
9.4 Design and construction considerations
9.5 Determination of earth pressures
9.6 Water pressures
9.7 Ultimate limit state design
9.8 Serviceability limit state design
9 2 Li it t t
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9.2 Limit states
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9.3.2 Geometrical data
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9 3 Geo et ca data
9.3.2 Geometrical data
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100%
10 %
100%
10 %
9.4 Design and construction considerations
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g
9.4 Design and construction considerations
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g
9 4 2 D i t
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9.4.2 Drainage systems
9 5 Determination of earth pressures
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9.5 Determination of earth pressures
9.5 Determination of earth pressures
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p
9 5 3 Limiting values of earth pressure
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9.5.3 Limiting values of earth pressure
Annex C also provides charts and formulae for the active
and passive limit values of earth pressure.
Annex C Sample procedures to determine limit values
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of earth pressures on vertical walls
• Based on Caquot and
Kerisel (and Absi?).• No values for adverse wall
friction, which can lead to
larger Ka and much smallerKp.
Wall friction
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Adverse wall friction may be
caused by loads on the wallfrom structures above, inclined
ground anchors, etc.
C 2 Numerical procedure for obtaining passive pressures
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C.2 Numerical procedure for obtaining passive pressures
• Also provides Ka
• Programmable formulae (though not simple)
• Incorporated in some software (eg Oasys FREW, STAWAL)• Precise source not known (to me), but same values as
Lancellotta, R (2002) Analytical solution of passive earth
pressure. Géotechnique 52, 8 617-619.• Covers range of adverse wall friction.
• Slightly more conservative than Caquot & Kerisel when φ and
δ/φ large – but more correct?
Ka, Kp charts in Simpson & Driscoll
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9 7 Ultimate limit state design
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9.7 Ultimate limit state design
9.7.2 Overall stabili ty
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9.7.3 Foundation failure of gravity walls
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9.7.4 Rotational failure of embedded walls
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9.7.5 Vertical failure of embedded walls
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9.7.6 Structural design of retaining structures
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9.7.6 Structural design of retaining structures
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9.7.7 Failure by pull-out of anchorages
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9.8 Serviceability limit state design
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9.8.2 Displacements
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Brussels, 18-20 February 2008 – Dissemination of information workshop 52
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
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, y p
EN 1997-1 Eurocode 7
Section 9 – Retaining structuresFundamentals – Design Approaches
Main points in the code text
Examples:Comparisons with previous (UK) practiceComparison between Design Approaches
Lessons from the Dublin Workshop
8m propped wall BP87.71 BP111.33 BP112.49
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8m propped wall - data BP78.26 BP111.34
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p ppBP112.50 BP119.50 BP124-F3.15
CASE: DA1-1
DA1-2
EC7SLS
Unplanned overdig (m) 0.5 0.5 0
Dig level: Stage 1 -8.5 -8.5 -2.5
Stage 2 -8.0 Characteristic φ' ( ) 24 24 24
γ (or M) on tan φ' 1 1.25 1
Design φ' 24 19.6 24
δ'/φ' active 1 1 1 δ'/φ' passive 1 1 1
K a 0.34 0.42 0.34
Factor on K a 1 1 1
Design K a 0.34 0.42 0.34 K p 4.0 2.9 4.0
Factor on K p 1 1 1
Design K p Excd. side
Retd. side
4.0 2.9 4.0
1.0 γQ 1 1.3 1
8m propped wall - length and BM BP78.28
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BP111.35 BP112.51 BP119.51 BP124-F3.16
CASE: DA1
-1 DA1
-2 EC7
SLS
Unplanned overdig (m) 0.5 0.5 0
Design φ' 24 19.6 24
Design K a 0.34 0.42 0.34
Design K p Excd. side
Retd. side 4.0 2.9 4.0
1.0
γQ 1 1.3 1
Computer program STW STW F
Data file PROP11 PROP1 BCAP3A
Wall length (m) 15.1
* 17.9
* 17.8
**
Max bending moment
(kNm/m) 1097 1519 -236
+682
Factor on bending moment 1.35 1 1
ULS design bending
moment (kNm/m) 1481 1519 -236
+682
* Computed ** Assumed
Redistribution of earth pressure BP87.75 BP111.36 BP112.52
BP119.52 BP124-F3.17
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Compare CIRIA 104 BP87.2 BP111.54 BP112.54 BP119.53 BP124-F
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10kPa (13kPa)
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0
-8m (-8.5m)
φ′ = 24° (19.6°)
. 0
630kN/m
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x b c a p 5 - F e b 0 7 c
E v e n t 3 R u n 3
I n c r e m e n t 1 1 1 : 2 8
2 1 - 0 2 - 0 7 : B e n d i n g m o m e n t
- 2 0 . 0 0
- 1 6 . 0 0
- 1 2 . 0 0
-
8 . 0 0 0
- 4 . 0 0 0
y c o o r d i n a t e ( x = - 0 . 5 0 0 0
m )
S c a l e x 1 : 1
0 1
y 1 : 1 3 6 8 1
- 1 2 0 0 .
- 1 0 0 0 .
- 8 0 0 . 0
- 6 0 0 . 0
- 4 0 0 . 0
- 2 0 0 . 0 . 0
2 0 0 . 0
4 0 0 . 0
Bending moment [kNm/m]
630kN/m
8m propped wall - length and BM BP78.32
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BP111.38 BP112.55 BP119.54 BP124-F3.19
CASE: CIRIA
Fs CIRIA
Fs BS
8002
DA1
-1 DA1
-2 EC7
SLS DA1
-1 DA1
-2 DA1
-2 DA1
-2 Unplanned overdig (m) 0 0 0.5 0.5 0.5 0 0.5 0.5 0.5 0.5
Design φ' 16.5 24 20.4 24 19.6 24 24 19.6 19.6 19.6
Design K a 0.49 0.36 0.41 0.34 0.42 0.34 0.34 0.42 0.42 Design K p Excd. side
Retd. side 2.1 3.4 2.8 4.0 2.9 4.0
1.0 4.0 2.9
1.0 2.9
1.0
γQ 1 1 1 1 1.3 1 1 1.3 1.3 1.3
Computer program STW STW STW STW STW FREW FREW FREW FREW SAFE
Data file PROP4 PROP5 PR1B-03 PROP11 PROP1 BCAP3A BCAPBA BCAP1A BCAP4A XBCAP5
Wall length (m) 20.4
** 14.1
** 17.9
* 15.1
* 17.9
* 17.8
**
17.8
** 17.8
** 17.8
** 17.8
**
Max bending moment
(kNm/m)
1870
##
776 1488 1097 1519 -236
+682
-241
838
1359 -308
1158
-229
1131Factor on bending moment 1.5 1.0? 1.35 1 1 1.35 1 1 1
ULS design bending
moment (kNm/m) 1164 1488? 1481 1519 -236
+682
-325
1131
1359 -308
1158
-229
1131
* Computed ** Assumed ## Not used in design
8m excavation - comparison of methods BP78.34
BP111.39 BP112.56 BP119.55 BP124-F3.20
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0
5
10
15
20
25
30
35
C I R I A 1 0 4
B S
8 0 0 2
E C 7
- S T W
E C 7 -
F
R E W
E C 7 -
S A F E
Length (m)
BM/50
Prop F/50
Redistribution of earth pressure BP87.75 BP111.36 BP112.5
BP119.56 BP124-F3.21
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German practice for sheet pile design - EAB (1996) BP87.39 BP111.37 BP112.5
BP119.57 BP124-F3.22
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SAFE Grundbau2 BP116.24 BP119.58 BP124-F3.24
2m
q=80kPa
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8m
φk′=35°
γ= 17 kN/m3
/ φ = 2/3 (active)
Ka = 0.224
?
γ = 20 kN/m3
22.4
30.5
15.3
Weissenbach, A, Hettler, A and Simpson, B (2003) Stability of excavations. In Geotechnical Engineering
Handbook, Vol 3: Elements and Structures (Ed U Smoltczyk). Ernst & Sohn / Wiley.
3.32m
Grundbau in STAWAL BP119.59 BP124-F3.25
60 0 0 400 0 200 0 0 2 00 0 4 00 0 600 0
Bending Moment [kNm /m ]
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[1 ]
.0
[2] [2]
-8.000
Toe-10.59m
.0 .0
199.3kN/m
Ac tua l Press uresWa ter Pres sureMomentShear
-24 0.0 -160.0 -80.00 .0 8 0.00 1 60 .0 240.0
-60 0.0 -400.0 -200.0 .0 2 00.0 4 00 .0 600.0
-24 0.0 -160.0 -80.00 .0 8 0.00 1 60 .0 240.0
Press ure [kPa]Shear Force [kN/m ]
Scale x 1:128 y 1:128
-14.00
-12.00
-10.00
-8.000
-6.000
-4.000
-2.000
.0
2.000
R e d u c e d L ev el [ m ]
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Brussels, 18-20 February 2008 – Dissemination of information workshop 68
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
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EN 1997-1 Eurocode 7
Section 9 – Retaining structuresFundamentals – Design Approaches
Main points in the code text
Examples:
Comparisons with previous (UK) practiceComparison between Design Approaches
Lessons from the Dublin Workshop
Eurocode 7 Workshop
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69 ©
Dublin, 31 March to 1 April 2005BP130.1
Organised byEuropean Technical Committee 10
Technical Committee 23 of ISSMGE
GeoTechNet Working Party 2
Retaining Wall Examples 5 to 7
Example 5 – Cantilever Gravity Retaining Wall BP130.2
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0.75m
B = ?
6m
0.4mFill
Sand
20o
Surcharge 15kPa • Design situation- 6m high cantilever gravity retaining wall,
- Wall and base thicknesses 0.40m.
- Groundwater level is at depth below the base of the wall.- The wall is embedded 0.75m below ground level in front of the wall.
- The ground behind the wall slopes upwards at 20 o
• Soil conditions- Sand beneath wall: c'k = 0, φ'k = 34
o, γ = 19kN/m3
- Fill behind wall: c'k = 0, φ'k = 38o, γ = 20kN/m3
• Actions
- Characteristic surcharge behind wall 15kPa
• Require- Width of wall foundation, B
- Design shear force, S and bending moment, M in the wall
Example 5 BP130.3
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0.75m
B = ?
6m
0.4m
Fill
Sand
20o
Surcharge 15kPa
20o
Kaγz
Example 5 BP130.4
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0.75m
B = ?
6m
0.4m
Fill
Sand
20o
Surcharge 15kPa
20o
Kaγz
Example 5 – Cantilever Gravity Retaining Wall BP130.5
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Example 5 - Gravity wall
1 b
2 N1
2
3 N1
N
1
N
N
N
N
N
1=3
2 2=N
b b
1
2
3
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0 0 1 1 1 2 2 2 2 2 3 3 3 5 5 5 8 8 16 16 17 G C C C C C C C
B A S E W I D T H
m
C:\BX\BX-C\EC7\Dublin\ Dublin-results.xls
1 , 2 or 3 – EC7 DA1, DA2 or DA3
b – EC7 DA1 Comb 1 only
N – national method
Contributor
Example 5 – Cantilever Gravity Retaining Wall B P1 30 .2 B P1 24 .A 6. 11
Surcharge 15kPa• Design situation
- 6m high cantilever gravity retaining wall,
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0.75m
B = ?
6m
0.4m
Fill
Sand
20o- Wall and base thicknesses 0.40m.- Groundwater level is at depth below the base of the wall.
- The wall is embedded 0.75m below ground level in front of the wall. - The ground behind the wall slopes upwards at 20
o
• Soil conditions- Sand beneath wall: c'k = 0, φ'k = 34
o, γ = 19kN/m3
- Fill behind wall: c'k = 0, φ'k = 38o, γ = 20kN/m3
• Actions- Characteristic surcharge behind wall 15kPa
• Require- Width of wall foundation, B
- Design shear force, S and bending moment, M in the wall
Additional specifications provided after the workshop:
1 The characteristic value of the angle of sliding resistance on the interface between wall and concrete under the
base should be taken as 30º.
2 The weight density of concrete should be taken as 25 kN/m3.
3 The bearing capacity should be evaluated using to the EC7 Annex D approach.
4 The surcharge is a variable load.
5 It should be assumed that the surcharge might extend up to the wall (ie for calculating bending moments in the
wall), or might stop behind the heel of the wall, not surcharging the heel (ie for calculating stability).
Example 5 – Cantilever Gravity Retaining Wall BP124.A6.12
Examp le 5 - Gravity w all
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3
2
1
bb
2=N2
1=3
N
N
N
N
N
1
N
1N3
2
1N2
b1
0.0
1.0
2.0
3.0
4.0
5.0
6.0
0 0 1 1 1 2 2 2 2 2 3 3 3 5 5 5 8 8 16 16 17 E C C C C C C C
B A S E
W I D T H m
Example 5 – Cantilever Gravity Retaining Wall BP130.5
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E E{ F Frep; Xk/ M; ad} = Ed ≤ Rd = R{ F Frep; Xk/ M; ad}/ R
Example 5 – Cantilever Gravity Retaining Wall BP130.5
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Column no. 1Characteristic values of all parameters.
Column no. 2
Characteristic eccentricity and
inclination; forces and resistance
factored.
Column no. 3
Characteristic eccentricity; unfavourable
(horizontal) force and resistance
factored. Favourable (vertical) force not
factored in deriving inclination or for
comparison with resistance.
Column no. 4
Unfavourable (horizontal) force and
resistance factored. Favourable
(vertical) force not factored in derivinginclination or eccentricity, but factored
for comparison with resistance.
Column no. 5
Unfavourable (horizontal) force and
resistance factored. Favourable
(vertical) force not factored in deriving
inclination or eccentricity, or forcomparison with resistance.
Column no. 1 2 3 4 5
Base width 3.75 3.75 3.75 3.75 3.75
Eccentricity (m) 0.57 0.57 0.57 0.79 0.79
Effective width B' (m) 2.61 2.61 2.61 2.17 2.17
Vertical force kN/m 690 941 690 941 690
Horizontal force kN/m 207 285 285 285 285
Inclination H/V 0.30 0.30 0.41Seenote 0.41
R (kN/m) 1392 1373 879 659 659
γ(R) 1 1.4 1.4 1.4 1.4
Rd (kN/m) 1392 981 628 471 471
Rd/Vd 2.02 1.04 0.91 0.50 0.68
Example 5 – Cantilever Gravity Retaining Wall BP124.A6.12
Example 5 - Gravity wall
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321bb2=N
2
1=31
b 21
N
1
N N
N N
0
200
400
600
800
1000
1200
0 0 1 1 1 2 2 2 2 2 3 3 3 5 5 5 8 8 16 16 17 G C C C C C C C
B E N D I N G M O
M E N T
k N
m / m
.
Example 5 – Cantilever Gravity Retaining Wall BP124.A6.14
Example 5 - Gravity w all
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321bb
2=N
2
NN
N
N
1
N1b
1
0
50
100
150
200
250
300
0 0 1 1 1 2 2 2 2 2 3 3 3 5 5 5 8 8 16 16 17 E C C C C C C C
S H E A R F O
R C E
k N / m
.
Example 5 – Cantilever Gravity Retaining Wall BP130.8
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• Serviceability: – No criteria in the instructions
– Mainly ignored
– ½(Ka + K0) ?
– Middle third ?
• Very large range of results
• Importance of sequence of calculation and factoring – this is the main difference between the design approaches for
this problem
• Factors of safety must allow for errors andmisunderstanding
Example 6 – Embedded sheet pile retaining wall BP130.9
10kPa
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Sand
10kPa
3.0m
D= ?
1.5m
• Design situation- Embedded sheet pile retaining wall for a
3m deep excavation with a 10kPa
surcharge on the surface behind the wall
• Soil conditions- Sand: c'k = 0, φ'k = 37o, γ = 20kN/m3
• Actions- Characteristic surcharge behind wall
10kPa
- Groundwater level at depth of 1.5m below ground surface behind wall and at
the ground surface in front of wall
• Require
- Depth of wall embedment, D- Design bending moment in the wall, M
Example 6 – Embedded sheet pile retaining wall BP130.9
10kPa
• Design situation
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Sand
3.0m
D= ?
1.5m
- Embedded sheet pile retaining wall for a3m deep excavation with a 10kPa
surcharge on the surface behind the wall
• Soil conditions- Sand: c'k = 0, φ'k = 37
o, γ = 20kN/m
3
• Actions
- Characteristic surcharge behind wall10kPa
- Groundwater level at depth of 1.5m
below ground surface behind wall and at
the ground surface in front of wall
• Require
- Depth of wall embedment, D
- Design bending moment in the wall, M
Additional specifications provided after the
workshop:1 The surcharge is a variable load.
2 The wall is a permanent structure.
Example 6 – Embedded sheet pile retaining wall BP130.14
Kp(C&K) /
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• Huge range of results
• Values of Kp ?
• C&K / EC7 / Coulomb ??
• What about overdig?
• 2.4.7.1(5) Less severe
values than those
recommended in Annex A may
be used for temporary
structures or transient design
situations, where the likely
consequences justify it.
Kp(C&K) /
Kp(EC7) %
Example 7 – Anchored sheet pile quay wall BP130.16
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10kPa
D = ?
1.5m
Tie bar anchor
3.0m3.3m
Sand
Water
GWL
8,0m
• Design situation- Anchored sheet pile retaining wall for an 8m
high quay using a horizontal tie bar anchor.
• Soil conditions
- Gravelly sand - φ'k = 35o, γ = 18kN/m
3
(above water table) and 20kN/m3 (belowwater table)
• Actions- Characteristic surcharge behind wall 10kPa
- 3m depth of water in front of the wall and a
tidal lag of 0.3m between the water in front of
the wall and the water in the ground behind
the wall.
• Require
- De th of wall embedment D
Example 7 – Anchored sheet pile quay wall BP130.16
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10kPa
D = ?
1.5m
Tie bar anchor
3.0m3.3m
Sand
Water
GWL
8,0m
• Design situation- Anchored sheet pile retaining wall for an 8mhigh quay using a horizontal tie bar anchor.
• Soil conditions
- Gravelly sand - φ'k = 35o, γ = 18kN/m3
(above water table) and 20kN/m3
(belowwater table)
• Actions- Characteristic surcharge behind wall 10kPa- 3m depth of water in front of the wall and a
tidal lag of 0.3m between the water in front ofthe wall and the water in the ground behind
the wall.
• Require- De th of wall embedment D
Additional specifications provided after the
workshop:
1 The surcharge is a variable load.2 The wall is a permanent structure.
3 The length of the wall is to be the minimum
allowable.
Example 7 – Anchored sheet pile quay wall BP130.23
Example 7 - Bend ing mom ents
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b
N
NN2
331
b N
1 1
b1*
N
Nb
bb
N
N
N N bc 1
b
1
N
b1
2
3
NN
N
31
2
b
12
3
N
3
0
100
200
300
400
500
600
0 0 0 0 0 0 0 A A 2 2 2 2 2 2 3 3 3 3 5 5 5 7 7 7 7 8 9 D 12121213141616 B C C C C C 1515151515
B E
N D I N G M O M E N T k
N m / m
. - not the end of the design
Eurocode 3, Part 5BP87.78 BP130.26
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Economies of up to 30% due to plastic design
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Example 7 – Anchored sheet pile quay wall BP130.28
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• Large range of results
• SSI important
• Optimise: length, BM, anchor force?
• Design doesn’t end at the bending moment• Nobody considered SLS
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The wall must be 12m long.
What tie force is required? BP87.114
BP99.90 BP130.37
As a cantilever, length would be about 14m. BP87.115 BP99.91
BP130.38
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DA1 Comb 2 gives a tie force of 75kN BP87.116
BP99.92 BP130.39
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Brussels, 18-20 February 2008 – Dissemination of information workshop 94
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997-1 Eurocode 7
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EN 1997-1 Eurocode 7
Section 9 – Retaining structures
Fundamentals – Design ApproachesSlopes and walls all one problemDesign Approaches matter!
Main points in the code textGood basic check listsValues of Ka and Kp
OverdigNot enough attention to SLS (by users, at least)
Examples:Results broadly similar to existing practiceDAs: big effect on gravity walls; small effect on embedded
Lessons from the Dublin WorkshopVery wide range of resultsEffect of DAs for gravity walls and Kp for embeddedHuman error important – partly offset by safety factorsNeed to work with EC3-5
Brussels, 18-20 February 2008 – Dissemination of information workshop 95
EUROCODESBackground and Applications
EN1997-1: Anchorages and Retaining structures
EN 1997 1 Eurocode 7
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EN 1997-1 Eurocode 7Section 8 – Anchorages
Section 9 – Retaining structures
Brian Simpson Arup Geotechnics