Björn Isaksen - Design of Hardanger Suspension Bridge

8/13/2019 Bjrn Isaksen - Design of Hardanger Suspension Bridge

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Design of Hardanger Suspension Bridge


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Design team 6 from Bridge Section

2 from NPRA

2-3 consultants (Norconsult AS)

Other specialists in wind engineering

meteorology, geology and tunnelling,concrete technology


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General view


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Box girder cross section


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Guide vanes and vortex spoiler


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Inspection and maintenance trolley


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Towers


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Cross beams in tower


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Rock anchors


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Rock anchor details


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Main cables


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Main cables Aerial spinning

19 strands in each cable

528 wires in each strand

Wire diameter 5.30 mm Wrapping: wire diameter 3.5 mm

Cableguard: Polyethylen (PE) Installation of a dehumidification system


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Dehudimification system


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Suspender and sockets


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Cross section of suspender cable


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Design basis Wind measurements at the bridge site

Wind tunnel investigations- Terrain model

- Section model of the bridge girder

CFD analysis / numeric simulation of the

wind flow

Geological investigations for the towersand the main cabel anchorages


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Wind tunnel terrain model


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Buffeting theory of wind load The shape factors are valid for

fluctuating wind loads as well as formean wind loads.

Wind fluctuations converts momentarily

to load fluctuations.

The bridge girder is a line-like (small

diameter) object without influence onthe overall properties of the flow.


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21

2

2

( , )

( , )( , )

D D

L L

S M

q x t C D

q x t U C Bm x t C B

=


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cos sin 0

( , ) sin cos 0

0 0 1

y D

tot z L

S

q q

x t q q

q m

= =

q

[ ]T

( , )x t u w=v andT

( , ) y zx t r r r = r

212

2

D

L

M

C DV C B

C B

=

q 12

2 2

22

2

D D L

q L D L

M M

C D C D C BV C B C D C B

C B C B

= +

B

12

2 2

2 0

2 0

2 0

D D L

ae L D L

M M

C D C D C B

V C B C D C B

C B C B

= +

C212

2

0 0

0 0

0 0

D

ae L

M

C D

V C B

C B

=

K

( , )tot q ae aex t = + + +q q B v C r K r&


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Flutter derivatives (FD)


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Stability limit flutter velocity Selberg flutter

Wind tunnel measurements

Multimode analysis in frequency domain

Analysis in time domain (direct timeintegration)

Analysis in time domain and modal

coordinates


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0 0.2 0.4 0.6 0.8 1

-2

-1

0

1

2Eigenmodes

x/L

i,

i=zor

First vertical symmetric

Second vertical symmetric

First torsion symmetric


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0 20 40 60 80 100 120-10

-8

-6

-4

-2

0

2

V [m/s]

[deg]

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Björn Isaksen - Design of Hardanger Suspension Bridge