1
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Introduction to composite bridges
Conceptual design of composite bridges in Europe
Erection of composite bridges
Introduction to composite bridges
Conceptual design of composite bridges in Europe
Erection of composite bridges
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Conceptual design of composite
bridges in Europe
Conceptual design of composite
bridges in Europe
3FKA – UTM 2012 4FKA – UTM 2012
2
5FKA – UTM 2012
EPFL
6FKA – UTM 2012
7FKA – UTM 2012 8FKA – UTM 2012
3
9FKA – UTM 2012 10FKA – UTM 2012
Content
► Two beams bridges
► Box section bridges
► Truss bridges
► Arch bridges
► Cable stayed bridges
11FKA – UTM 2012
Pont sur la baie de Montreux, 1968SwitzerlandSpan length: 60 mBridge length: 275 m
Pont sur la baie de Montreux, 1968SwitzerlandSpan length: 60 mBridge length: 275 m
12FKA – UTM 2012
Bridge over la Chandelard, 1973SwitzerlandSpan length: 50 mBridge length: 245 m
4
13FKA – UTM 2012
14FKA – UTM 2012
15FKA – UTM 2012 16FKA – UTM 2012
Weathering steel
5
17FKA – UTM 2012
Weathering steel
18FKA – UTM 2012
19FKA – UTM 2012
Pont Napoléon, 1980Span length: 60 - 83 mSwitzerlandBridge length: 330 mCurvature in plan: R = 600 m
20FKA – UTM 2012
Pont Napoléon, 1980Span length: 60 - 83 mSwitzerlandBridge length: 330 mCurvature in plan: R = 600 m
6
21FKA – UTM 2012
Pont de Châtillon, F, 1988Span length: 50 mBridge length: 240 mCurvature in plan: R = 320 m
22FKA – UTM 2012
Viaduc de Monestier, F (2007)
23FKA – UTM 2012
Viaduc de Monestier, F (2007)
24FKA – UTM 2012
Viaduc de Monestier, F (2007)
7
25FKA – UTM 2012Launching procedure
Viaduc de Monestier, F (2007)
26FKA – UTM 2012
Viaduc de l’Elle, F (2008)
27FKA – UTM 2012
Viaduc de l’Elle, F (2008)
28FKA – UTM 2012
Viaduc de l’Elle, F (2008)
8
29FKA – UTM 2012
Pont sur la LosentzeSwitzerland, 1985
Two closed small boxes
30FKA – UTM 2012
Pont sur la Losentze Switzerland, 1985
31FKA – UTM 2012
Pont sur la LosentzeSwitzerland, 1985
32FKA – UTM 2012
9
33FKA – UTM 2012 34FKA – UTM 2012North American Steel Construction conference April 6 34
The Dala Bridge, Switzerland 1989
Legs erected vertically,
then inclined, pulling the main girders
35FKA – UTM 2012North American Steel Construction conference April 6 35
The Dala Bridge, Switzerland 1989
36FKA – UTM 2012North American Steel Construction conference April 6 36
The Dala Bridge, Switzerland 1989
10
37FKA – UTM 2012
slab
Studconnector
wind
supportcross
bracing
pile plan bracingfor erection
main beam
[mm] Span Support
width 300 à 700 300 à 1200
depth 15 à 40 20 à 100
depth 10 à 18 12 à 22
width 400 à 1200 500 à 1400
depth 20 à 70 40 à 120
Usual sizesFor continuous beams
With a span length : 30 – 80 m
38FKA – UTM 2012
Content
► Two beams bridges
► Box section bridges
► Truss bridges
► Arch bridges
► Cablestay bridges
39FKA – UTM 2012 40FKA – UTM 2012
11
41FKA – UTM 2012
Bois de rosset bridge, Switzerland 1990
42FKA – UTM 2012
Bois de rosset bridge, Switzerland 1990
43FKA – UTM 2012
Bois de rosset bridge, Switzerland 1990
44FKA – UTM 2012
Bois de rossetbridge,
Switzerland1990
12
45FKA – UTM 2012
Veveyse, Switzerland, 1969 (129 m)
46FKA – UTM 2012
Two long 130 m main spans
Height of the central piers: 100 m
Total length: 945 m
The Vaux viaduct, Switzerland 1999
47FKA – UTM 2012
Description of the Viaduct
40 56 56 56 56 56 56 62 62 62 130 6213016 45
945 m
R=1000 m
R=1000 m
N
Crane
Crane
Launching
Launching
48FKA – UTM 2012
diaphragms
13.46 m6.00 m 3.73 m3.73 m
4.28
-6.4
0 m
longitudinaland transversestiffeners
Section for the 130 m main spans
Description of the Viaduct
13
49FKA – UTM 2012
Section for the shorter spans
Description of the Viaduct
0.2
5 m
0.40
m
3.40
m
13.46 m6.00 m 3.73 m3.73 m
50FKA – UTM 2012
Erection Procedure
51FKA – UTM 2012
Verrières F (144 m), 2002
Span length: 80 – 144 m
Bridge length: 720 m
Piles height: 141 m
52FKA – UTM 2012
Content
► Two beams bridges
► Box section bridges
► Truss bridges
► Arch bridges
► Cablestay bridges
14
53FKA – UTM 2012
Tubular trusses
Railbridge Olten, Switzerland 2003Span Length: 44 m
54FKA – UTM 2012
Tubular trusses
Hagneck Bridge, Switzerland 2004
55FKA – UTM 2012
Hagneck Bridge, Switzerland 2004
56FKA – UTM 2012
Tubular trusses
Lully Bridge, Switzerland 1999
15
57FKA – UTM 2012
Lully Bridge, Switzerland 1999
58FKA – UTM 2012
59FKA – UTM 2012
Lully Bridge, Switzerland 1999
60FKA – UTM 2012
Three roses bridge, Basel, 2004
77 m 105 m 84 m
16
61FKA – UTM 2012
Three roses bridge, Basel, 2004
62FKA – UTM 2012
Pont d’Antrenas, France 1994
Tubular trusses
63FKA – UTM 2012
Sindelfingen Footbridge,
Germany 1989
Tubular trusses
64FKA – UTM 2012
Traun Bridge, Germany 2000
Tubular trusses
17
65FKA – UTM 2012
Nesenbachtal Bridge, Germany 2000
Tubular trusses
66FKA – UTM 2012
section en travée
Bern 26 m 26 m39 m 39 m 39 m 39 m
215 m
Zurich
Construction duration8 month
Tubular trusses
Dättwil Bridge 2001
67FKA – UTM 2012
Dättwil Bridge 2001
68FKA – UTM 2012
Dättwil Bridge 2001
18
69FKA – UTM 2012
Branson Bridge, Switzerland 2006
70FKA – UTM 2012
Branson, Fully, (60 m)
71FKA – UTM 2012
Branson Bridge, Switzerland 2006
72FKA – UTM 2012
Content
► Two beams bridges
► Box section bridges
► Truss bridges
► Arch bridges
► Cablestay bridges
19
73FKA – UTM 2012
St Triphon (90 m),
Switzerland, 1980
74FKA – UTM 2012
Landquartbrücke, Switzerland, 1990 (123 m)
75FKA – UTM 2012
Mornas, TGV French, 1999 (121 m)
76FKA – UTM 2012
Garde Adhémar, French, 1999 (135 m)
20
77FKA – UTM 2012Pont de l‘Europe, F, Orléans, 2000,(202 m) 78FKA – UTM 2012Pont de l‘Europe, Orléans (202 m)
79FKA – UTM 2012
Reggio Emilia, Italia Calatrava, 2008
221 m
80FKA – UTM 2012
Reggio Emilia, Calatrava, 2008
179 m
21
81FKA – UTM 2012The Gateshead Millennium Bridge, England, 2001 (105 m)
82FKA – UTM 2012
The Gateshead Millennium Bridge, England, (105 m)
83FKA – UTM 2012
Content
► Two beams bridges
► Box section bridges
► Truss bridges
► Arch bridges
► Cable stayed bridges
84FKA – UTM 2012
St-Maurice, Switzerland, 1986 (110 m)
Cable stayed bridges
22
85FKA – UTM 2012
Pont sur la Poya, Fribourg Switzerland, 2013Span length: 196 mBridge length: 851 m
Cable stayed bridges
86FKA – UTM 2012
Pont sur la Poya
87FKA – UTM 2012
Pont sur la Poya
88FKA – UTM 2012
Normandie, F (856 m), 1995
23
89FKA – UTM 2012
The Millau viaduct 200490FKA – UTM 2012
The Millau viaduct
91FKA – UTM 2012
The Millau viaduct
92FKA – UTM 2012
The Millau viaduct
24
93FKA – UTM 2012
The Millau viaduct
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Erection of composite bridgesErection of composite bridges
95FKA – UTM 2012
Content
► Steel structureFrom the ground by craneLaunchingCantilever
► Concrete slabSlab cast in-situ,Slab launched in stages,Precast slab.
96FKA – UTM 2012
MONTAGE A LA GRUE DEPUIS LE SOL
From the ground by crane
25
97FKA – UTM 2012
From the ground by crane
98FKA – UTM 2012
From the ground by crane
99FKA – UTM 2012 100FKA – UTM 2012
LANCEMENT
By launching
26
101FKA – UTM 2012
By launching
102FKA – UTM 2012
By launching
103FKA – UTM 2012 104FKA – UTM 2012
By launching
27
105FKA – UTM 2012
By launching
106FKA – UTM 2012
By launching
107FKA – UTM 2012
By launching
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By launching
28
109FKA – UTM 2012
ENCORBELLEMENT
Cantilever erection
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111FKA – UTM 2012
Cantilever erection
112FKA – UTM 2012
Cantilever erection
29
113FKA – UTM 2012
Lifting of a span
114FKA – UTM 2012
Content
► Steel structureFrom the ground by craneLaunchingCantilever
► Concrete slabSlab cast in-situ,Slab launched in stages,Precast slab.
115FKA – UTM 2012
DALLE COULEE SUR PLACE AVEC COFFRAGE MOBILE
Slab cast in-situ
Slab cast in-situ
116FKA – UTM 2012
Slab cast in-situ
30
117FKA – UTM 2012
Slab cast in-situ
118FKA – UTM 2012
Slab cast in-situ
119FKA – UTM 2012
Slab cast in-situ
120FKA – UTM 2012
Slab cast in-situ
31
121FKA – UTM 2012
Slab cast in-situ
122FKA – UTM 2012
Slab cast in-situ
123FKA – UTM 2012
Slab cast in-situ
124FKA – UTM 2012
Prefabricated slab elements
32
125FKA – UTM 2012
Prefabricated slab elements
126FKA – UTM 2012
Prefabricated slab elements
127FKA – UTM 2012
Prefabricated slab elements
128FKA – UTM 2012
Prefabricated slab elements
33
129FKA – UTM 2012
Prefabricated slab elements
130FKA – UTM 2012
Prefabricated slab elements
131FKA – UTM 2012
Prefabricated slab elements
132FKA – UTM 2012
Prefabricated slab elements
34
133FKA – UTM 2012
Prefabricated slab elements
134FKA – UTM 2012
Prefabricated slab elements
135FKA – UTM 2012
Prefabricated slab elements
136FKA – UTM 2012
Prefabricated slab elements
35
137FKA – UTM 2012
Prefabricated slab elements
138FKA – UTM 2012
Prefabricated slab elements
139FKA – UTM 2012
Prefabricated slab elements
140FKA – UTM 2012
Prefabricated slab elements
36
141FKA – UTM 2012 142FKA – UTM 2012
Dättwil
Prefabricated slab elements
143FKA – UTM 2012
Lanching of the slab
144FKA – UTM 2012
Lanching of the slab
37
145FKA – UTM 2012
Lanching of the slab
146FKA – UTM 2012
Lanching of the slab
147FKA – UTM 2012
Lanching of the slab
148FKA – UTM 2012
Lanching of the slab
38
149FKA – UTM 2012
Lanching of the slab
150FKA – UTM 2012
151FKA – UTM 2012 FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
04/09/2012
1
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Design of composite bridges
Behaviour of composite bridges
Design of composite bridges according EC 4
Design of composite bridges
Behaviour of composite bridges
Design of composite bridges according EC 4
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Behaviour of composite bridgesBehaviour of composite bridges
3FKA – UTM 2012
Measured according strain
Measured according vertical deformation
calculated
0.1
0.9
For practical design
Transverse distribution line of loads
4FKA – UTM 2012
According to the traditionnal design, normal stresses in thesteel girders can be as high as 60 à 80 N/mm2 in compression in cross sections over intermediate supports !
Shrinkage effect
Free shrinkage
N corresponding
connected
04/09/2012
2
5FKA – UTM 2012
More elaborate calculation of shrinkage effects taking into account of teconcrete behaviour (cracks, creep)
Shrinkage effect
6FKA – UTM 2012
cs, inf [N/mm2]
Shrinkage effect – compression stresses in the lower flange contraintes over intermediate support
Calculation for twenty existing composite bridgesWith span length between 30 and 120 m (cs = 0.25 ‰)
-25 N/mm2
Design value
Shrinkage effect
7FKA – UTM 2012
measurements calculation according code
Temperature effect
8FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h2850
400
Tamb = 16°C
Temperature effect
04/09/2012
3
9FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h2850
400
Tamb = 22°C
Temperature effect
10FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
2850
400
Tamb = 26°C
Temperature effect
11FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
2850
400
Tamb = 29°C
Temperature effect
12FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
] 0h
2h
4h
6h
8h
10h
2850
400
Tamb = 34°C
Temperature effect
04/09/2012
4
13FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
10h
12h
2850
400
Tamb = 35°C
Temperature effect
14FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
10h
12h
14h
2850
400
Tamb = 33°C
Temperature effect
15FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
10h
12h
14h
16h
2850
400
Tamb = 26°C
Temperature effect
16FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
10h
12h
14h
16h
18h
2850
400
Tamb = 21°C
Temperature effect
04/09/2012
5
17FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
10h
12h
14h
16h
18h
20h
2850
400
Tamb = 19°C
Temperature effect
18FKA – UTM 2012
0
1
2
3
4
5
15 20 25 30 35 40 45
température [°C]
haut
eur
[m]
[m
]
0h
2h
4h
6h
8h
10h
12h
14h
16h
18h
20h
22h
2850
400
Tamb = 18°C
Temperature effect
19FKA – UTM 2012
0
0.1
0.2
0.3
0.4
-4 -2 0 2 4
contraintes [N/mm2]
haut
eur
[m]
[m]
section 1
section 4
section 5
section 7
128 m
130 m
42 m
portées42 m
Max tension stresses in the concrete slab
max = 1.7 N/mm2
span
Temperature effect
20FKA – UTM 2012
Max compression stresses in the steel girder
0
1
2
3
4
5
-30 -20 -10 0 10 20
contraintes [N/mm2]
haut
eur
[m]
section 1
section 4
section 5
section 7
128 m
130 m42 m
portées42 m
Webmax ≈ -20 N/mm2
Lower flangemax ≈ - 5 N/mm2
Upper flangemax ≈ - 20 N/mm2
span
Temperature effect
04/09/2012
6
21FKA – UTM 2012
Measurements during Erection ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
22
Measurements
Example of vertical reaction results
0
1
2
3
4
5
6
0 10 20 30 40
Movement ofthe bridge
[m]
Reaction [MN]
calculated values
tolerancezone: ± 15 %
measured values
level adjustments
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
23
20 25-70
-60
-50
-40
-30
-20
-10
0
10
2
1
3
4
Ver
tic
al
str
es
se
s [
N/m
m2]
Bridge position [m]30
1
3
2
4
Example of vertical stress results
Measurements ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
24
2354 kN 4114 kN
16 mm 21 mm
max =2.0 mm
max =1.5 mm
1000
mm
South bridgeStage 5
South bridge stage 8Web lateral deformation
Measurements
04/09/2012
7
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
25
Temperature during concrete hydration
0
5
10
15
20
25
30
35
40
24.02 25.02 26.02 27.02 28.02 1.03 2.03 3.03 4.03
Date
Tem
pera
ture
[°C
] Concrete slabSteel girderTamb
25.5 h
5
8°C
28°C
<70 cm
Measurements ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
26
Slab cracking
Durability
Origin of tensile stresses
What to do
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
27
Slab cracking
After demolition, however no corrosionof the stud shear connectors
28FKA – UTM 2012
Slab cracking
04/09/2012
8
29FKA – UTM 2012
Durability of the slabSlab transverse cracking tolerated if:
- Good etancheity well put in place
- Good detailing of the slab well constructed
- crack opening lower than 0.4 mm
Longitudinal reinforcement: about 1,5% on intermediate support (conceptual design)
about 0.7% in span (minimum reinforcement)
But over all: compact concrete
Take measures to avoid cracking if they are “simple” need to know the orign of crackingVery very good durability need to introduce longitudinal prestressing in the concrete slab
30FKA – UTM 2012
Origin of tensile stresses
• Hydratation effects of the concrete slab
• Construction of the slab
• Direct actions (traffic,…)
• Indirect actions (shrinkage,…)
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
31
Tensile stresses in the slab [N/mm2]Origin Span 30.0 m Span 80.0 m
Hydratation effects 0.6 1.8
Concreting end to end 1.8 2.7Surfacing 0.8 1.3Traffic 0.3 0.1Shrinkage 0.8 1.4
Tensile stresse are the highest during the construction of the slab (hydration and concreting) 60%
Origin of tensile stresses ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
32
Stresses due to hydratation t
= 0.9 N/mm2 –1.3
[ N/mm 2
–1.319.6
19.6
Moments dus à T
Système statique
1
3
2
stressesIn section 2 :
2.2
2.2–34.2
–34.2
Ec = 8 kN/mm2= +25°
Ec = 25 kN/mm2= -25°
Hydration effects
04/09/2012
9
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
33
Temperature during concrete hydration
0
5
10
15
20
25
30
35
40
24.02 25.02 26.02 27.02 28.02 1.03 2.03 3.03 4.03
Date
Tem
pera
ture
[°C
] Concrete slabSteel girderTamb
25.5 h
5
8°C
28°C
<70 cm
Measurements ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
34
Steps of concreting (slab cast in-situ)
Construction of the slab
1 2 3 4 5 6 7 8
direction of concreting
1 2 5 4 3 8 7 6
direction de concreting
Concreting end to end
Concreting “piano”
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
35
Steps of concreting end to end
2t=2.7 /mmN
4500
1 5 6 7 82 3 4TRANSVERSE CRACKING
Span: 80 m
Construction of the slab ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
36
Span 80.0 m
13’000
4’500
c = 2.7 N/mm2End to end
c = - 0. 5N/mm2Piano
Tensile stresses in the slabSpan 30.0 m
12’500
1’900
2c = 1.8N/mm
End to end
2c = - 0.2 N/mm
Piano
Construction of the slab
04/09/2012
10
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Design of composite bridges
according EC 4
Design of composite bridges
according EC 4
38FKA – UTM 2012
Main selected features
• General presentation and scope of EC’s related to steel and composite bridges
• Structural analysis
• Cross-section analysis at ULS and SLS
• Fatigue
39FKA – UTM 2012
Eurocodes (EN)
EN 1990 basis of design
EN 1991 actions
EN 1992 concrete
EN 1993 steel
EN 1994 composite
EN 1995 timber
EN 1996 masonry
EN 1997 geotechnic
EN 1998 seismic
EN 1999 aluminium
EN 1991 : actions
EN1991-1-1 densities… EN1991-1-3 snow EN1991-1-4 wind EN1991-1-5 thermal actions EN1991-1-6 execution EN1991-1-7 accidental actions EN1991-2 traffic
04/09/2012
11
EN 1992 : concrete
EN 1992-1-1 general rules
EN 1992-2 bridges
42FKA – UTM 2012
Partie 2
bridges
Partie7.1
pylons
Partie7.2
chimneys
Partie 6
Cranes
Partie4.2
tanks
Partie4.3
Pipelines
Partie 5
pilingapplications
Partie 1.1
General rulesbuilding
Partie 1.2
fire
Partie 1.3
sheetings
Partie 1.4
Stainless steel
Partie 1.5
Plated elements
Partie 1.6
shells
Partie 1.7
Plated elements loaded transv.
Partie 1.8
joints
Partie 1.9
Fatigue
Partie 1.10
Brittle fracture
Partie 1.11
cables
Partie 4.1
Silos
Partie 1.12 S500 to S690
Eurocode 3 : steel structures
EN 1994 : composite structures
EN 1994-2 general rules and bridges
Based on EN 1994-1 and EN 1993 - 2
44FKA – UTM 2012
Structural analysis
linear(material)
non linear
steel
concrete
04/09/2012
12
45FKA – UTM 2012
Elastic
Plastic (buildings, bridges in span)
Structural analysis ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
46
Classes of steel cross-sections
Cl.1
Cl.2Cl.3
Cl.4
Mpl
Mel
1 3 6
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
47Cl.1 Cl.3 / 4
All the sections class 1 : plastic analysis (not for bridges)
Some sections class 2 : elastic analysis up to Mpl,Rd
Some sections class 3 : elastic analysis up to Mel,Rd
Large composite bridges (in general)
Classes of steel cross-sections ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
48
Class of webs
04/09/2012
13
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
49
Class of flanges
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
50
Class of a cross section
Corresponds to the largest class of all the elements
A composite section is generally class 1 under positive moment due to the location of the PNA (the web is in tension)
Actual design
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
51
Cracking of concrete in a composite bridge
If under characteristic combination 2fctm c cracked global analysis
EI1EI2
EI1
Cracked zone
Structural Analysis ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
52
Example of cracked zones in a composite bridge 60-80-60 m
17 %15,6 % 23 % 17,7 %
ctm2f 6, 4MPa
-12
-10
-8
-6
-4
-2
0
2
4
6
8
0 20 40
60
80 100 120
140
160 180
200
Structural Analysis
04/09/2012
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ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
53
Alternative if– No prestressing (tendons or jacking on supports)
– lmin/lmax>0.6
EI1EI2
EI1
Imin Imax
0.15Imax
Structural Analysis
Cracking of concrete in a composite bridge
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
54
Elastic calculation of bending moments
Elastic verification of sections– Over support (local buckling of compressed web)– In span
Plastic verifications of sections also possible– In span
Actual design - ULS
Actual design
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
55
• Redistribution due to plastification at mid-span is neglected except if :– Class 1 or 2 at mid-span (if MEd > Mel,Rd )– Class 3 or 4 on support– Lmin/Lmax < 0.6
• Non-linear elastic analysis or• Linear elastic analysis with MEd < 0.9 Mpl,Rd in
sagging moment regions
Cl.1/2
Cl.3 / 4
M
Linear elastic analysis of a composite bridge and plastic strength in span ÉCOLE POLYTECHNIQUE
FÉDÉRALE DE LAUSANNE
56
Max bending in span Max bending over support
Elastic calculation of bending moments
Actual design
04/09/2012
15
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
57
Load Model (road)
Design Load Model (SIA 261 <> Eurocode 1)
SIA 261 §10.3.1
Qi, qi et qr = 0.9
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
58
Transverse distribution line of loads
Transverse distributionline of loads
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
59
beff
bv
A
B C
DJ L
MNO
Deformation due to shear
Effectives width ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
60
Equivalent spans Le for slab effectives width
Effectives width
Actual design
04/09/2012
16
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
61
Effectives width of concrete slab
b1 b1 b2
be1 be2
beff
b0
eei i
Lb min( ; b )
8
0eff i eib b b with e
iei
L0,55 0,025 1
b end supports
i 1 elsewhere
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
62
Elastic calculation of bending moments Elastic verification of sections
– Over support (local buckling of compressed web)
Check - ULS
Elastic design procedure over support
fy/a
s fys/s
fy/a
Steel sectionLoad during erection
Steel + reinforcement sectionLoad on composite sections
Localbuckling
partial factor = 1,05
partial factor = 1,15
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
63
Check – ULS in span
ResistingSteel alone
Resistingcomposite
unpropped during erection
propped during erection
Dead loadSteel concrete
Perm. loadSurfacing traffic
~ 6 = Ea/Ec~ 18
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
64
Modular ratio used in a composite section
L 0 L tn n . 1
Value of t0 : t0 = 1 day for shrinkage
t0 = a mean value in case of concrete cast in several stages
a0
cm
En
E t 0t t creep coefficient given by EC2 : and
L is given by : Permanent loads
shrinkageImposed deformations
1,10,551,5
04/09/2012
17
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
65
Elastic calculation of bending moments Elastic verification of sections
– In span
PNA
ENA
Elastic resistance (for class 1, 2, 3)
fck/c
fy/a
compression
traction
partial factor = 1,5
partial factor = 1,05
Taking into account The load history and duration
Check - ULS ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
66
Elastic calculation of bending moments Plastic verifications of sections
– In span
Mpl,Rd
+
- -
+
xp
c = cu a ≥ y0,85 fck/a
fyd = fy/a
beff
h
a
Shrinkage and load history are neglected
partial factor = 1,5
partial factor = 1,05
Check - ULS
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
67
Plastic verifications of sections in span?
q
Q
Applicable only if L1/L2 ≥ 0.6L1 L2
Verification:
MEd ≤ red Mpl,Rd
red = 0.95
red = 0.90
Without load onsteel section aloneWith load onsteel section alone
M
Mpl
el
Mg
pl= 5 el
Actual design - ULS ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
68
Longitudinal shear v
Design of the connexion
04/09/2012
18
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
69
Design of the connexion in the elasto-plastic region of the span
Bending moment
Shear force
longitudinal shear
Elasto-plastic region
FA FB
Design of the connexion
Longitudinalshear in elasto-plasticregion
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
70
Design of the connexion in the elasto-plastic region of the span
Design of the connexion
FB
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
71
Design of the connexion in the elasto-plastic region of the span
Design of the connexion
bending
Elasto-plasticregion
Longitudinalshear
Stud resistance
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
72
Resistance of stud shear connectors
hd
21uRk
dP 0,8 f4
2 2cmRk ck
P 0,29 d f E
1 2Rk Rk RkP min(P ;P )
and
h0,2. 1d
ifh3 4d
1If not
RdP75.0
25.1Rk
Rd
PP At U.L.S.
At S.L.S.
Design of the connexion
04/09/2012
19
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
73
Verification at SLS
Limitation of stresses– As in EN1992-2 and EN1993-2 (fy in the steel
part)
Limitation of crack widths– As in EN1992-2 with tension stiffening
(wk=0.3mm in general)
– Using a simplified method
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
74
Fatigue verification in EC3
Calculation of E,2 under a fatigue loading
Influence of the type of influence line Influence of the type of traffic Influence of the number of lanes
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
75
Fatigue verification in EC3
verificationpartial factor for loading = 1,0
Category of detail
Actual design
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
76
Fatigue SN curves in EC3
C
Fatigue verification in EC3
Actual design
04/09/2012
20
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
77
C for each detail
Fatigue verification in EC3
Actual design FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
04/09/2012
1
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
Innovative design of steel-concrete composite bridges
Innovative design method
Innovative connection
LTB
Innovative design of steel-concrete composite bridges
Innovative design method
Innovative connection
LTB
UTM – 2012 2
Innovative design method for steel-concrete composite plate girder bridges
• Introduction, context
• Basis of the new design method
• Step by step procedure
• Conclusion, exemple
UTM – 2012 3
Introduction, context
• Current analysis of steel-concrete composite bridges: EER and EE or EP
• Need to consider:• Loading history• Shrinkage and creep of concrete
• Long and tiresome calculations for an illusory precision
Cl.1Cl.3 / 4Cl.1
UTM – 2012 4
Introduction, context
0
100
200
300
400
0 25 50 75 100
FB1 [mm]
F [kN]
Deformationcapacity
Under negative bending moment, slender composite beams show some deformation capacity
This deformation capacity is called
Available rotation capacity av
of the composite beam in the support region
04/09/2012
2
UTM – 2012 5
• How to use the available rotation capacityover support ?o To redistribute bending moments from supports
to span
o When span region in elasto-plastique domain, to redistribute bending moments from span to supports
• Requiers some rotation capacity fromcross-sections over supports
Required rotation capacity req
• Verification:
over support
Basis of the new design method
req av
UTM – 2012 6
av
Mref
Mel,Rd
Rdelref MM ,9.0
0.9 takes into account of the load history
Available rotation capacity av
M
Basis of the new design method
UTM – 2012 7
Available rotation capacity av
av is a function of:
Shear force if VEd > 0.8 VRd
Slendernesses of the web and of the compressed flange
Position of the neutral axis
Steel grade
Basis of the new design method
UTM – 2012 8
Available rotation capacity av
E
f
kt
bf y
w
w
cr
yp
05.1
5.05.0'
5.05.0 si
'p
Cla
ss 1
2'
75.15
p
vc
FEM results
63 mrad
010203040506070
0.0 0.5 1.0 1.5 2.0
av [mrad]
Existing composite bridges
4m
rad
< a
v<
24 m
rad
Basis of the new design method
04/09/2012
3
UTM – 2012 9
Required rotation capacity req
req = req,1 + req,2
req,1: redistribution of bending moments from
intermediate supports to the span
req,2 : use of elasto-plastique domain
in span
Basis of the new design method
UTM – 2012 10
Required rotation capacity req,1
Ed
EdrEd
M
MM
,
l [m]
req,1 [mrad]
req,1
M
- Ed
0
10
20
30
40
50
60
70
20 30 40 50 60 70 80 90 100
= 0.1 = 0.2 = 0.3
Basis of the new design method
UTM – 2012 11
Required rotation capacity req,2
pl
Edr
M
M ,
req,2
M +r,Ed
pl,span
0
10
20
30
40
50
60
70
20 30 40 50 60 70 80 90 100
0.95 0.9
0.85 0.8
0.75 0.7
= 0.95= = 0.75
= 0.90= = 0.70
0.800.85
req,2 [mrad]
l [m]
Basis of the new design method
UTM – 2012 12
Required rotation capacity req
= 0.3
= 0.2
= 0.1
= 0.0
req = req,1 + req,2
pl
Edr
M
M ,
Ed
EdrEd
M
MM
,0
10203040506070
0.70 0.80 0.90 1.00
req [mrad]
Basis of the new design method
04/09/2012
4
UTM – 2012 13
Existing bridges
Allow to find hidden bearing capacity(evolution of the traffic loading)
Design method applicable with otherassumptionso Larger deflection
o Use of updated load models
Allow to take into account of longitudinal stiffeners on the web
Basis of the new design method
UTM – 2012 14
0
20
40
60
80
0.0 0.5 1.0 1.5 2.0
av [mrad]
Existing bridges
'p
Influence of a longitudinal stiffener
2'
75.15
p
vc
Without stiffener
av,sup = 40 – 46 VEd / VRd si h1 = 0.2 hw
av,sup = 28 – 31 VEd / VRd si h1 = 0.3 hw
stiffener
0
20
40
60
80
0.0 0.5 1.0 1.5 2.0
av [mrad]
UTM – 2012 15
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure to apply the new design method
UTM – 2012 16
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
04/09/2012
5
UTM – 2012 17
Step by step procedure
Shear force:
Distance between lateral supports of the compressed flange (lateral torsional buckling):
RdEd VV 80.0
y
fcD f
EbL
3225.0
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
UTM – 2012 18
Over support:
M
Mrefav
elref MM 9.0
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
UTM – 2012 19
In span:
M
Mpl
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
UTM – 2012 20
E
f
kt
bf y
w
w
cr
yp
05.1
5.05.0'
010203040506070
0.0 0.5 1.0 1.5 2.0
av [mrad]
av
5.05.0 si
'p
Cla
ss 1
2'
75.15
p
vc
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
04/09/2012
6
UTM – 2012 21
Ed
EdrEd
M
MM
,
Max. bending moment over the support:
M +r,Ed
M -Ed
M -r,EdM
- Ed
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
UTM – 2012 22
M +Ed
Max. bending moment in the span:1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
UTM – 2012 23
Ed
EdrEd
M
MM
,
l [m]
req,1 [mrad]
0
10
20
30
40
50
60
70
20 30 40 50 60 70 80 90 100
= 0.1 = 0.2 = 0.3
req,1
av ≥ req req,1 req,2 req,2
req,2 < 0 (req,1 too large) step 1
req,2 ≥ 0 following step
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
UTM – 2012 24
av
= 0.3 = 0.2
= 0.1 = 0.0pl
Edr
M
M ,
0
10
20
30
40
50
60
70
0.70 0.80 0.90 1.00
req [mrad]1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
04/09/2012
7
UTM – 2012 25
RdplEd MM ,
RdplEdr MM ,,
Verification over the support (indirect):
Verification in the span:
avreq
1. PRELIMINARY DESIGN
2. PRELIMINARY CONDITIONS
3. RESISTANCE OF CROSS-SECTIONS
4. AVAILABLE ROTATION CAPACITY
5. BENDING MOMENTS
6. REQUIRED ROTATION CAPACITY
7. PLASTIC MOMENT UTILIZATION RATIO
8. VERIFICATIONS
Step by step procedure
UTM – 2012 26
Conclusion
Example
Appui Travée
UTM – 2012 27
Conclusion
Analysis ElementCross-sections
supportCross-sections
in spanCross-sections
area [%]Benefit
EER, EESupport,span
Upper fl.webLower fl.
1000× 12022 × 2560
1200 × 120
700 × 4014 × 2700800 × 60
Support : 100Span : 100 -
EER, supportEP, span
Upper fl.webLower fl.
1000× 12022 × 2560
1200 × 120
700 × 4014 × 2720800 × 40
Support : 100Span : 86
14 %span
New method
Upper fl.webLower fl.
1000× 10022 × 2600
1250 × 100
700 × 4014 × 2720800 × 40
Support : 88Span : 86
12 % support14 % span
UTM – 2012 28
Conclusion
The new design method makes it possible to carry out a calculation of structural safety nearer to the behaviour of the structure and more precise
The advantages which result from this are numerous and are related to the plastic design of the structures:
The history of the loading and the visco-elastic behaviour of the concrete can be neglected at ULS
Better optimization of the cross-sections of the beams
Very interesting Method for the verification of the safety of existing bridges
04/09/2012
8
TUM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Innovative Steel Concrete Connection for Composite BridgesInnovative Steel Concrete Connection for Composite Bridges
Prof., Dr, Jean-Paul Lebet, ICOMSwiss Federale Institute of Technology, Lausanne
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
30TUM 2012
Contents
► Introduction
► New connection
► Resistance of the connection
► Design model
► Fatigue
► Conclusions
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
31TUM 20121. Introduction
Joints
Needs: durability, short duration of on-site work
Steel – concrete composite solutions with concrete precast elements
Context ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
32TUM 2012
Rapid and durable connection with prefabricated slab
Context
04/09/2012
9
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
33TUM 2012
Connexion ?Joints ?
Needs: durability, short duration of on-site work
Context ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
34TUM 2012
Context
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
35TUM 2012
Glued joints
Context ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
36TUM 2012
Précontrainte
Joints
Connection
Welding on site
Context
04/09/2012
10
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
37TUM 2012
Preliminary push-out tests with cement paste on differentconnection types
Precast concrete slab
Steel beam
connection types
Cement paste
New steel-concrete connection ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
38TUM 2012
HR
HP
HH
R
HR
Embossed steel plate and bonding layer HRPerfobond and bonding layer HPBonding layer HHStud connectors DEmbossed steel plate RPerfobond P
Load
[kN
]
Slip [mm]
push-out tests
New steel-concrete connection
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
39TUM 2012
Precast concrete slab
Steel beam
Cement paste
Embossed steel plate
Bonding layer
New connection definitionLongitudinal rib (rough concrete)
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
40TUM 2012
New connection definition
04/09/2012
11
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
41TUM 2012
Connection behaviour - Confinement
ec-4
ec-6
Uplift u perpendicular to sheared interfaces
Opening of cracks
Uplift 2u [mm]
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
42TUM 2012
Slip s Force v
Normal stresses Shear sresses v = b x
Slip s Uplift u
Uplift u Normal stresses
s, v
Embossed steel plate
Cement paste
Concrete slab
Connection behaviour - Confinement
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
43TUM 2012
Effet of the uplift u1
2conf,1 conf,3 slab 1 3 imp,2
1( ) ( ) ( )
bs s k u u
b
Deformed positionInternal stresses
,2
Connection behaviour - Confinement ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
44TUM 2012
Slab rigidity crackdeformed position
Connection behaviour - Confinement
04/09/2012
12
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
45TUM 2012
Numerical model
Numerical modelconfinement effect-modelling of the relationship between the confinement stress, σ and the uplift, u
Connection behaviour - Confinement
cracking of concrete
yielding of middle reinforcement
no further increase
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
46TUM 2012
Interfaces’ behaviourDirect shear tests
Interface behaviour
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
47TUM 2012
Interfaces’ behaviour
Ribbed steel Concrete UHPFRC
Interface behaviour ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
48TUM 2012
Failure criteria max -
Interface behaviour
04/09/2012
13
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
49TUM 2012
2 ( ) N/mmu c
Failure criteria for the three interfaces
Failure criteria
Interface behaviour ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
50TUM 2012
2( )( )
(1 )
uSu uu a uSu max Su
u s s s s u s s s
u u u e s s
independent of the normal stress, σ
Interface behaviour
Kinematic law u - s
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
51TUM 2012
elk
plk
/
el el
u pl el el u
u afr u fr u
k s s s
k s s s s s τ s s s s
e s s
1 2
du s τ s C +C
ds
Constitutive law - s
Interface behaviour ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
52TUM 2012
Experimental investigation and modelisationdirect shear tests on small scale specimens
static loading
Embossed steel-cement grout interface
Interface behaviour
04/09/2012
14
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
53TUM 2012
u3
3
s3
s
s
= 1
= 1
= 2
= 2
s
u
u
1 s1
s
s2
conf
u2
2
max,1
max,2
2
1
Failure criteria
Kinematical law s - u
Constitutive law - s
confinement
Interface behaviour ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
54TUM 2012
s
u
Interface 2
Interface 1 Interface 3
Interface 4
Mechanical Model of the connexion
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
55TUM 2012
Experimental work with large scale specimens and analytical study
static push-out tests on large scale speciments
55
Connection behaviour ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
56TUM 2012
Connection behaviourmodel validation
04/09/2012
15
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
57TUM 2012
Longitudinal shear force versus slip, comparison between a fatigue and static test (push-out)
Connection behaviourFatigue ÉCOLE POLYTECHNIQUE
FÉDÉRALE DE LAUSANNE
58TUM 2012
Cyclic loading of interfaces – final results
embossed steel-cement grout interface
Connection behaviourFatigue
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
59TUM 2012
59
cyclic loading
Safe fatigue failure criterion for the new connection:
No failure due to cyclic loading occurs in the connection as long as theaccumulated slip under maximum applied longitudinal shear force isinferior to the slip which corresponds to failure for static loading.
Vmax,N us s
1 connu
fVmax,1
bs
Ns
The resistance of the connection to longitudinal shear under cyclic loadingcan be assessed by the structural performance for static loading !
Connection behaviourFatigue ÉCOLE POLYTECHNIQUE
FÉDÉRALE DE LAUSANNE
60Institute of Steel Structures - Xi’an University of Architecture & Technology
Composite beams behaviour
4. Comportement des poutres mixtes
Connections by adherence exhibit a limited ductility !
Beam behaviour ?, elastic, plastic, connection failure ?
4 to 8 metres
3 x 1000 kN
04/09/2012
16
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
61TUM 2012
Composite beams behaviour
Connections by adherence exhibit a limited ductility !
However full plastic resistance of the cross-section can be reached
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
62TUM 2012
Test of a composite beam under fatigue load and ultimate
P=275 (1-sin3.14t) KN
2P/3P/3
Pmax = 550 KNPmin = 140 KN
vmax= 537 KN/mvmin = 137 KN/m
Composite beams behaviour
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
63TUM 2012
Test of a composite beam
major results
Composite beams behaviour ÉCOLE POLYTECHNIQUE
FÉDÉRALE DE LAUSANNE
64TUM 2012
50 m long injection test of the connection
04/09/2012
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UTM – 2012 65
Lateral torsional buckling in bridge design
Design according european normalisation
New research
UTM – 2012 6666
LTB in bridge design (new research)
UTM – 2012 67
a) Canal bridge Mitelland. (Germany, 1982)
b) Highway bridge Kaiserslautern. (Germany, 1954)
c) Saint-Ilpize bridge. (France 2004)
LTB in bridge design (new research)
UTM – 2012 68
The method for instability problem
Critical stress for the first mode corresponding to the studied instability
Yield strength
cr
yf
Reduced slenderness
Theory
y
cr
f
Theory / Tests
Reduction curve f 1,0Verification
y
EdM1
f
Partial factor : M1 1,1 Statistical analysis / Tests
Simplified method
LTB in bridge design - usual verifications
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UTM – 2012 69
Critical load for column buckling
2cr
cr 2
N 1 EI
L
NEd
NEd
L
2 2cr
cr2 2
N1 EI 1 1 EI2 EIc
L l
NEd
NEd
L
ll
l
Note : These formulae assume that I and are constant over the whole length L.
(Euler’s formula)
(Engesser’s formula)
with c = Cd / l
(springs supposed to be uniformly distributed)
LTB in bridge design - usual verifications
UTM – 2012 70
• deformable section (because of a very slender web)
• variation of the flange thicknesses
• variation of the bending moment My
• transverse distribution of the traffic loads, so benefit effet of the less loaded girders
•the transverse frames introduce discrete lateral elastic support
• « typical » method - rarely usable
• 3D model would be necessary (2 girders + transverse frames)
• second order elastic analysis for better taking into account the imperfections (equivalent geometric, or geometric + residual stresses)
LTLT
Particularities of bridge girders
Consequences
LTB in bridge design - usual verifications
UTM – 2012 71
General method from EN1993-2, 6.3.4.1
• ultimate amplification factor
yfult,k
Ed
minf
Ed is the ULS stress in the mid-plane of the flange in compression.
• critical amplification factor
crcr,op
Ed
cr is the stress in the mid-plane of the flange in compression, corresponding to the first mode for LTB.
• slenderness
ult,kop
cr,op
• reduction factor
op 22op
11,0
2
op op1
1 0,22
with
• Verification:
ult,kop
M1
1,0 with M1 1,1
LTB in bridge design - usual verifications
UTM – 2012 72
7000
28
00
11
006
001
100
IPE 600
B
BC
A A
C
280
0
7000
15
00
A A
B
B
Transverse frames in spans Transverse frames on supports
60,00 m 80,00 m 60,00 m
a = 8 m a = 7,5 ma = 7,5 m
Elastic lateral support with a rigidity of the transverse frame Cd = 20,3 MN/m
calculated by assuming:• hinges at the interface steel/concrete• extensibility of the slab neglected
Fixe lateral support(by comparison with transverse frames in the spans)
The bridge
LTB in bridge design - usual verifications
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UTM – 2012 73
60,00 m 80,00 m 60,00 m
C0 P1 P2 C3
280
0
272
0
269
0
264
0
256
0
269
0
272
0
264
0
269
0
264
0
256
0
264
0
269
0
272
0
bfi = 1200 mm
tfi (mm) = 40 55 80120
80 55 40 55 80120
80 55 40
Acier S355
LTB in bridge design - usual verifications
UTM – 2012 74
-120
-100
-80
-60
-40
-20
0
20
40
60
0 50 100 150 200
Abscisse x (m)
Mo
men
t E
LU
dév
erse
men
t (M
N.m
)
poutre n°1 - la plus sollicitée
poutre n°2
Dead loads (construction phases, cracked elastic analysis, shrinkage)
Traffic loads (udl and TS with unfavourable transverse distribution for the girder n°1)
TS = 409,3 kN/axleudl = 26,7 kN/m
LTB during service life on support P1 (lower flange in compression)
+
LTB in bridge design - usual verifications
UTM – 2012 75
ANE
hw,c
hw,c 3*
sup
inf
-20
-10
0
10
20
30
40
50
0 20 40 60 80 100 120 140 160 180 200
Abscisses (m)
Eff
ort
no
rmal
(M
N)
Poutre n°1 la plus sollicitéeh tA b t w,c w
eff f f 3
t bI
3f f
12
Use of Engesser’s formula with:
• isolated central span (L=80m) considered on an elastic soil with uniform rigidity c = Cd /a
• use of the maximum thickness on support
• use of the maximum normal force on support
crit 2N EIc
crit 191,9 MNN
crit 1154,8 MPa
LTB in bridge design - usual verifications
UTM – 2012 76
NormFasc. 61 titre V
1978
SIA 161
1990
SIA 263
2003
EN 1993-2, 6.3.4.2
2007
Conditions for the function LT
n = 2,25
Welded section
=> Curve c
Welded section
h/bf = 2800/1200 > 2
=> Curve d
0,904 0,980 0,840 0,776
1,0 1,1 1,05 1,1
266,7 MPa-9,6 %
262,8 MPa-10,9 %
236 MPa-20,0 %
208,1 MPa-29,5 %
Ok? YES YES NO NO
LT
yLT
crit
0,505 0,4f
M1
Ed 249,25 MPa (first order on support P1)
LT y
RdM1
f
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UTM – 2012 77
Mode cr,op Description of the observed deformed shape
1 8,86
Anti symmetric waves with a buckling length Lf = 20 m around P1
2 10,26
Anti symmetric waves with a buckling length Lf = 20 m around P2
3 17,49
Quasi symmetric waves with a buckling length Lf = 20 m around P1
• bar model with a unique girder (Af + Aw,c/3)
• variable inertia and normal force
• discrete elastic lateral support, with rigidity Cd
a = 8 ma = 7,5 m a = 7,5 m
x
uy
60 m 60 m80 m
EN 1993-2, 6.3.4.1
LTB in bridge design - usual verifications
UTM – 2012 78
-400
-300
-200
-100
0
100
200
300
400
0 20 40 60 80 100 120 140 160 180 200
Co
ntr
ain
tes
dan
s le
pla
n m
oye
n d
e la
sem
elle
in
f (M
Pa)
yfult,k
f
295118
249 25min ,
,
f
ult,k
op
cr,op
1,180,365 0,2
8,86
2op opLT LT
11 0,2 0,63
2
op 22opLT LT
10,875 1,0
ult,kop
M1
1,0360,94 1,0
1,1
NO
• the section where cr,op is maximum can be located in another place in comparison with the section where ult,k is minimum.
• ult,k can be minimum in the section where the flange thickness changes.
LTB in bridge design - usual verifications
UTM – 2012 79
Field of bridges
Different curves for LTB in bridges
LTB in bridge design - usual verifications
UTM – 2012 80
-200
-150
-100
-50
0
50
100
150
200
250
300
0 20 40 60 80 100Str
esse
s (M
Pa
)
First order stressesSecond order stresses - mode 1Total stresses - mode 1
C0 P1
0 20 40 60 80 10
First order stressesSecond order stresses - mode 3Total stresses - mode 3
P1C0
• definition of the equivalent geometric imperfection (shape + amplitude e0 = L/150)
• calculation by EF with an elastic analysis
• zoom on the area of P1
Second order elastic analysis
LTB in bridge design - usual verifications
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UTM – 2012 81
Mode 1 1 3 3
e0 Lf/150 Lf/300 Lf/150 Lf/300
max (MPa) 74,58 37,57 50,44 25,41
in the section x (m) 64,5 64,5 50 50
total max (MPa) 271,00 247,76 278,81 262,52
in the section x (m) 62,5 60 (P1) 60 (P1) 60 (P1)
Always verified : max yf 295 MPaf YES
• II is mainly due to the first iteration of the second order analysis (quasi proportional to the value of e0).
• e0 should be defined following the value of the reduced slenderness parameter.
el0
We 0,76 0,2
A use (so 25 mm instead of L/150 = 133 mm)
Second order elastic analysis
LTB in bridge design - usual verifications
UTM – 2012 82
There is a need for a “simplified” more accurate design method for bridge design
UTM – 2012 83
Methodology
LTB in bridge design (new research)
UTM – 2012 84
Residual stresses
• Longitudinal residual stresses at a macroscopic scale in thick
steel plates
• Origin: rolling, cutting and welding process
• Self-equilibrated system (∑M = 0 and ∑F = 0)
• Several models already exist but not for bridge sections
ECCS, n°33, 1984
(ECCS, n°22, 1976) (Flame-cutting, Welding)
LTB in bridge design (new research)
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UTM – 2012 85
Principle of the sectioning method
Initials measurements Li
Finals measurements Lf
Strain: Stresses:
LTB in bridge design (new research)
UTM – 2012 86
Specimens fabrication
• Flame-cutting set up and temperature measurements
1
2
3
LTB in bridge design (new research)
UTM – 2012 87
Expérimentaux sur contraintes résiduelles• Fabrication des éprouvettes d’oxycoupage
871. Introduction 2. Le projet 3. Travaux réalisés 4. Suite des travaux 5. Finances
UTM – 2012 88
Specimens fabrication
• Geometry of welding and pass sequencing
730
FC
FC
2600
60 730
Section View A-A
A
A
Plan view
Web PL20mm, S355J2 2600 x 180 x 20 mm
Flange PL60mm, S355N 2600 x 730 x 60 mm
20
180
Weld direction,
Speed 6.66 mm/s
T2b
Rolling direction
Temperaturemeasuring zones
1 12 2
3 3web
flange
123
1 23
Submerged Arc Welding process (SAW)
LTB in bridge design (new research)
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UTM – 2012 89
Specimens fabrication
• Welding set up and temperature measurements
LTB in bridge design (new research)
UTM – 2012 90
90
UTM – 2012 91
Preparation of the specimens
• Design of sectioning
13@20mm 13@20mm
2@25mm
60
5@10
mm
730
280 30 2805 55
6@10mm
70
6@10mm
70
1@15mm 1@15mm
9@20mm
60
5@10
mm
730
50 2005 55
6@10mm
70
6@10mm
70
1@15mm 1@15mm
70
6@10mm
1@15mm
6@10
mm
6@10
mm
2@17
.5m
m
9@20mm
200 70
6@10mm
1@15mm
Welding Specimens
Flame-cutting Specimens
LTB in bridge design (new research)
UTM – 2012 92
Preparation of the specimens
• Cutting steps2. Band saw
1. Circular saw
LTB in bridge design (new research)
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UTM – 2012 93
Preparation of the specimens
• Specimens after cutting
LTB in bridge design (new research)
UTM – 2012 94
Measuring techniques
b) Curvature deformationa) Longitudinal deformation
250 mm
“Needle comparator”“Deformeter”
LTB in bridge design (new research)
UTM – 2012 95
4. RESULTS AND DISCUSSION
LTB in bridge design (new research)
UTM – 2012 96
Temperature measurements
LTB in bridge design (new research)
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UTM – 2012 97
Flame-cutting residual stresses distribution for the 615 mm width plates
LTB in bridge design (new research)
UTM – 2012 98
Flame-cutting residual stresses distribution for the 730 mm width plate
LTB in bridge design (new research)
UTM – 2012 99
LTB in bridge design (new research)
Flame-cutting residual stresses distribution resume
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
04/09/2012
1
FKA – UTM 2012
ÉCOLE POLYTECHNIQUE FÉDÉRALE DE LAUSANNE
Prof., Dr, Jean-Paul Lebet Swiss Federale Institute of Technology, Lausanne
THE “VIADUCT DE MILLAU”THE “VIADUCT DE MILLAU”
North American Steel Construction conference, April 2
The Millau viaduct
3 4
04/09/2012
2
Viaduc de Millau
6
The Millau viaduct
Narrow and winding access roads
Height above ground
Long and innovative bridge
7
The Millau viaduct
8
The Millau viaduct
04/09/2012
3
9
The Millau viaduct
10
From North, 717 m
From south (descending), 1743 m
The Millau viaduct
Launching principle
11
The Millau viaduct
12
04/09/2012
4
13 14
The Millau viaduct
Translators used for the launching
15
The Millau viaductPrincipe of the launching
Avant-bec
Palée provisoire T1
Pile P1
Tablier du pont
Systèmes de lançage
04/09/2012
5
Step 0 – Initial position
Cinematic of the launching
Step 1 – up
Cinematic of the launching
Step 2 – Translation
Cinematic of the launching
Step 3 – Down
Cinematic of the launching
04/09/2012
6
Step 4 – Back to initial position
Cinematic of the launching
04/09/2012
7
28
The Millau viaduct
04/09/2012
8
29
The Millau viaduct
30
31 32
04/09/2012
9
33 34
35
The Millau viaduct
36
04/09/2012
10
37
Thank you for your attention