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From Bridges across Great Belt and resund towards a Femern Belt Bridge

Niels J GIMSINGProfesor Emeritus

Techn. Univ. of DenmarkDK-2800 Lyngby, Denmarknjg@byg.dtu.dk

Professor Emeritus at the

Department of Civil Engineering.

Participated in the design of theGreat Belt Bridge and the resundBridge, and acted as specialistdesign adviser on numerous bridgesaround the World . Co-owner ofGimsing & Madsen, ConsultingEngineers, Denmark.

Summary

In Denmark the construction of three major bridges was initiated in the 1990.s: Storeblt Bridge(Great Belt Bridge), resund Bridge and Femern Belt Bridge. The first two were completed in 1998

and 2000, respectively, and the third is expected to be constructed during the second decade of the

21st century. In both design and construction procedures a number of innovative features have been

introduced.

Keywords: Box girder bridge, suspension bridge, cable-stayed bridge, wind tunnel test, compositeaction.

1. Introduction

Denmark consists of the peninsula Jutland and

406 islands, out of which 79 are inhabited. The

second largest island, Funen, is separated from

Jutland by the strait Little Belt and from the

largest island, Zealand, by the strait Great Belt.

In round figures 45% of the population lives in

Jutland 10% on Funen and 45% on Zealand

were the capital Copenhagen is situated.

The substitution of ferry services by bridges

across the straits separating the different parts ofDenmark began in 1935 with the opening of the

bridge across the Little Belt and in 1937 with the

opening of the Storstrm Bridge between

Zealand and Falster. At the opening the 3.2 km

long Storstrm Bridge was the longest in Europe.

After the completion during the 1930.s of more

than ten bridges across a number of the smaller

straits in Denmark the country was virtually

joined in two infrastructure units separated by

the 18 km wide Great Belt.Fig. 1: Map of Denmark

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Plans to build the final link - across the Great Belt - were worked out already in the late 1930.s but

the outbreak of World War II and the subsequent post war period with lack of resources made it

impossible to consider construction of a Great Belt Bridge for a period of more than twenty years.

In 1978 the Great Belt Bridge was close to

reach the construction stage based on adesign with either a 780 m cable stayed-

bridge main span or a design with a 1416 m

suspension bridge main span across the

international navigation route between the

Baltic Sea and the North Sea.

The 1978 design never reached the

construction stage as the government

decided to give priority to a natural gas

distribution net throughout the country.

Finally in 1987 the Danish Parliament approved the construction of a fixed traffic link across the

Great Belt but now in a different configuration from that of 1978. In stead of carrying both the road

and the railway across the East Channel on a bridge it was decided to let the railway cross in a

bored tunnel and only carry the motorway across on a bridge. Across the West Channel both road

and railway should be on a bridge (as assumed in 1978) but in a different alignment.

2. Great Belt Bridge

The two bridges forming a part of the Great Belt crossing is the 6.6 km long West Bridge between

Funen and Sprog and the 6.8 km long East Bridge between Sprog and Zealand.

2.1 West BridgeThe West Bridge crosses domestic Danish waters without international restrictions regarding

navigational requirements. The West Bridge could therefore be constructed as a low level bridge

with a maximum vertical clearance of 18 m just to allow passage of coasters, fishing boats and

leisure vessels [1].

The most unique feature of the West Bridge is the

extensive use of precast elements for both thesubstructure and the superstructure. The elements

were cast on a work site area close to the bridge

abutment on Funen. Five production lines were

used to cast the caissons and the pier shafts as well

as the box girders for the road and the rail

superstructures.

The huge precast elements with a weight of up to

6000 tonnes (and slightly more) were moved onto a

load-out pier where they could be picked up by the

purpose built floating crane Svanen with a lifting

Fig. 2: Design from 1978 for a suspension bridgewith a 1416 m main span for both road and railway

Fig. 3: Casting yard on Funen

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capacity of 6000 tonnes. As some of the largest caissons had a weight in excess of the lifting

capacity they had to have their lower part submerged during transportation to utilize buoyancy.

The superstructure of the West Bridge is divided

into two parallel bridges with individual girders

for the road and the railway, whereas the caissonsin the substructure are common for both bridges.

The precast box girder elements have the full

length of the span (110 m) reaching from midspsn

to midspan. That allowed the floating crane to

pick up the girder elements at the center as the

post-tensioned reinforcement both in the

construction phase and in the final stage would

have the right position at the top of the girders

above the supports.

From erection of the first caisson to installatiom of

the last box girder elements a period of only 25 months elapsed.

2.2 East BridgeThe East Bridge crosses the international navigation route from the Baltic Seato the North Sea.Therefore, the bridge had to be designed so that the largest existing ships could pass safely through

the large main span across the navigation channel [2].

In 1978 it was believed that a 780 m span would be adequate to allow safe passage of the largest

ships provided that it could be assured that the very large ships could be guided through the main

span without encountering other ships in the immediate vicinity of the bridge. With a 1416 m span

it was believed that ships could pass the main span without restrictions.

Prior to tendering the East Bridge in 1990 a number of navigation studies were performed to ensure

that the bridge would not affect the safe passage through the Great Belt of even the largest ships. In

the meantime it also became clear that it would not be acceptable to impose one way passage of

large ships through the main span.

The final choice of the main span length of the East Bridge was based on manoeuvring simulations

carried out at the Danish Maritime Institute. Here the navigational safety was studied for main spansof 900 m, 1200 m, 1400 m and 1600 m by having experienced pilots and ship captains to

manoeuvre computer generated ships through the shipping lane under severe weather conditions.

The result of the navigational studies was that only with a main span of 1600 m (and a vertical

clearance of 65 m) could all the involved shipmasters agree that the bridge would have no

decremental effect on safe passage.

2.2.1 Approach spans

On either side of the 2700 m long suspension bridge approach bridges with lengths of 1600 m and

2500 m, respectively, have been constructed as continuous box girders in steel.

Fig. 4: The floating crane Svanen with aprecast element for the roadway

superstructure

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As for the West Bridge full span prefabricated elements were erected for the approach spans of the

East Bridge. However, due to application of steel the weight of a 193 m long girder element was

only 2500 tonnes in stead of the 5800 tonnes weight of the 110 m long precast elements of the West

Bridge.

The steel girders for the East Bridgeapproach spans were fabricated in Italy

and assembled into 193 m long erection

units on a work site area at Aalborg in

Denmark. From here they were

transported on a barge to the bridge site

and lifted onto the piers by two cranes

positioned at either end of the erection

unit.

The extreme end of the erection unit was

initially supported 4 m above the final level of the bearing and in this position the continuity at theother end was completed by site welding. Subsequently, the girder was lowered onto the final

bearing and by this procedure it was ensured that continuity would also be achieved for the dead

load of the steel girders.

During the detailed design of the East Bridge it was discovered that vortex excited oscillations of

the slender approach span girders with a depth-to-span ratio around 1/25 could be experienced even

for cross winds with a velocity of less than 25 m/sec. These vibrations would not endanger the

structural integrity of the bridge but could result in discomfort by the users of the bridge. It was,

therefore, decided to install large tuned mass dampers to eliminate all oscillations for wind speeds

below 25 m/sec. For wind speeds above 25 m/sec the bridge would in any case be closed to all

traffic so user comfort did not have to be considered.

Besides the tuned mass dampers a number of dehumidification plants are also installed inside the

box girders to exclude corrosion and make interior painting superfluous. This system was for the

fist time used in the box girder of the Little Belt suspension bridge from 1970 and has since then

been used intensively around the world as a most efficient way to exclude corrosion inside major

box girders.

2.2.2 Anchor Blocks

The anchor blocks of the East Bridge are located farfrom the coasts at open sea and they are therefore

very visible compared to anchor blocks on land

where they can be partly hidden behind vegetation

and buildings.

It was, therefore, important to arrive at a less

massive appearance than found in many existing

anchor blocks.

The anchor blocks are founded at a water depth of

approximately 10 m on 122 m long and 55 m wide precast concrete caissons. The upper visible partof the anchor blocks are cast in situ.

Fig, 5: Erection of a 193 m long box girder element forthe East Bridge approach spans

Fig. 6: Anchor block of the East Bridge

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2.2.3 Pylons

The two pylons reach a height of 254 m making them the

highest concrete pylons in the world at the time of construction.

The pylons are designed with a very simple and cleanappearance characterised by just two cross beams between the

quasi-vertical legs. In contrast to other large suspension bridges

there is no cross beam immediately below the deck but half way

to the top.

In situ casting was chosen as slipforming was abandoned by the

client and prefabrication of segments was unattractive due to

weight problems.

The batching plants were located on a work site area on Zealand

and transported to the pylons by truck mixers on ferry boats.After arrival at the pier the mixed concrete was pumped to the

top of the pylon and cast into the jump form.

In each pylon the total quantity of concrete amounted to nearly

40,000 m3.

2.2.4 Cables

Each main cable contains 18.648 galvanised wires with a minimum tensile stress of 1570 MPa and

a diameter of 5.38 mm.

Both the air-spinning method and the PPWS method was allowed by the client during bidding but

only the air-spinning method proved to be competitive [3].

2.2.5 Deck

The deck of the suspension bridge consists of a slender box girder in steel with a depth of 4.3 m and

a width of 31 m. It was fabricated in Italy in 48 m long segments and transported on a barge to

Denmark.

With a span approximately 15% longer than that of the

Humber Bridge there were special concerns aboutaerodynamic stability as past experience had indicated

that the critical wind speeds for bridges with a mono-

box deck would diminish as the span was increased.

Initially the wind tunnel tests were performed on

section models with different cross sectional layouts to

determine a suitable configuration.

The section model tests indicated that it would be

possible to achieve the required critical flutter wind

speed of more than 60 m/sec with the mono-box but to give a further verification of the adequacy itwas decided to test a full aeroelastic model in a scale of 1:200. As the continuous box forming the

Fig. 7: Pylon under construction

Fig. 8: Full bridge model in wind tunnel

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deck of the suspension bridge is 2700 m long it was necessary to build a special 14 m wide wind

tunnel at the Danish Maritime Institute.

The result of the extensive wind tunnel tests was a critical flutter wind speed of 72 m/sec,

comfortably higher than the limit of 60 m/sec. However, this was for a model with an open railing,

but the client also wanted to know the influence of adding wind screens to improve the user comfort.

Adding wind screens proved to have a decisive effect

as it reduced the critical flutter wind speed to 62 m/sec.

In contrast to the majority of existing suspension

bridges the deck of the Great Belt suspension bridge is

continuous from one anchor block to the other - and

with only lateral support at the pylons.

The omission of a pylon cross beam below the deck

and the continuity of the steel box clearly exhibits thefact that the vertical load of the deck is transferred to

the main cables through the hanger cables.

3. resund Bridge

The bridge constituting the eastern part of the resund Link has a total length of 7845 m and it

consists of three main sections: the western approach bridge with a length of 3014 m; the main

bridge (over the navigation channel) with a length of 1092 m; and the eastern approach bridge with

a length of 3739 m.

Fig. 10: The resund Bridge

.Across the navigation channel the main span has a length of 490 m and a vertical clearance (air

draught) of 56 m.

The bridge is the longest cable-stayed bridge in the world with both road and railway traffic, and it

is also one of the largest composite structures ever built [4].

3.1 Approach bridges

The two approach bridges have a combined length of 6753 m which constitutes approximately 85%

of the total length of the bridge. It was, therefore, evident from the initial design phase that the

emphasis should be laid on arriving at an optimum solution for these spans.

Fig. 9: Deck at pylon

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A double deck configuration offered the advantage of separating the train and automobile traffic

and at the same time the required stiffness would be achieved through the large structural depth

imposed by the clearance requirements above the railway tracks.

The double deck arrangement naturally leads to a structure with steel trusses between the two decks

which in turn can be incorporated as chords to achieve maximum structural efficiency. With thetrain load constituting the major part of the live load it was important to position the two vertical

main trusses just outside the clearance diagram of the railway so that the heavy load on the tracks

could be carried as directly as possible through transverse girders to the lower nodes of the main

trusses.

Fig. 11: Cross section and part elevation of approach spans

With the transverse position of the trusses determined by the clearance of the railway the wider

roadway deck had to be made with overhangs, i.e. the deck slab should be cantilevered on either

side of the trusses. This was in fact advantageous for the upper deck as it led to a favourable

distribution between positive and negative moments in the slab and thereby made it possible to

design the roadway deck as a solid concrete slab supported directly on the top chords of the main

trusses. With a span of 12 m between the top chords the concrete slab had to be designed with a

varying depth and with transverse prestressing.

The design of the trusses was influenced by a number of considerations. The geometrical layout

should be clean and simple not only for the overall appearance but also to give a harmonic rhythm

when viewed from a passing train, the truss should be maintenance friendly, and the truss should be

so rigid that it could respect the strictrequirements regarding deflections

under passing trains. The solution

was to use a Warren truss composed

of unilateral triangles with relatively

flat diagonals inclined approximately

45o in stead of the generally accepted

value of 60o (a value arrived at when

minimizing the quantity of structural

steel and neglecting the favourable cost implications of reducing the number of nodes). All truss

members are made as closed boxes with stiffeners and diaphragms inside so that the exterior

surfaces are clean and easy to maintain. The interior of all boxes is protected against corrosion byinstallation of dehumidification plants.

Fig. 12: Approach spans

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The most efficient use of the different structural materials would clearly be achieved by establishing

a composite action between the concrete slab and the top chords of the steel trusses. However, the

composite action should not only cover longitudinal shear but also bending moments between the

top chords and the concrete slab so that

a rigid closed frame could beestablished by the lower cross beams,

the diagonals of the truss and the upper

concrete deck. This required that the

top plate of the chords was equipped

with studs in two different sizes,

normal studs in the central region of the

top plate and long studs along the edges

(above the webs of the box shaped

chords).

The long studs would be efficiently anchored inside the concrete slab and thereby allow transfer ofthe moment as a couple consisting of two vertical forces of opposite sign. The short studs on the

other hand were only to transfer shear.

the assumption

For the design of the studs it was important to

investigate the interaction between the long and the

short studs to avoid that the long studs were

overstressed before the short studs were efficiently

activated.

In 1989 when a double deck truss bridge was

considered for the West Bridge of the Great Belt

Link a full scale test was performed at the

Department of Structural Engineering, Technical

University of Denmark. From this test it could be

concluded that it would be safe to base the design on

the assumption that total shear was equally

distributed over the long and the short studs whereas

the moment transfer only affected the long studs.

A great effort was made during the conceptual design

phase to design the main trusses in such a way thatthey were not only structurally efficient but also

pleasing in appearance. This resulted in gently curved

gusset plates in a configuration that was favourable in

relation to fatigue a feature of special importance

due to the train loading. Besides this it was also

decided to keep the exterior surfaces plane so that

variations in plate thickness were to be made by

adding thickness inside the box sections. This

implied a slight complication in the fabrication as the

interior diaphragms were to be geometrically adjusted as the side plate thickness was varied but this

proved to be of minor importance.

Fig. 13. Joint between the top chord and the upperconcrete slab

Fig. 14: Top chord with studs

Fig. 15: Test specimen in the structurallaboratory at Techn. Univ. of Denmark

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In the design of the trusses it was attempted to

minimize the number of structural elements to

give the structure a clear and logic layout. An

important step was to reduce the number of nodes

by having a diagonal inclination of approximately

450

. The effort resulted in a truss with only 64members within the span length of 140 m: 14 top

chord members, 14 bottom chord members, 28

diagonals and 8 transverse girders. In a traditional

truss with stringers, wind bracings and verticals in

the main trusses the number of members can

easily amount to more than 350.

The trusses of the approach spans are made

mainly of high strength steels S 460 N with a yield

stress of 460 MPa. Only the lower cross beams

and the top chord members between the gussetplates are made of S 355 N.

The steel structure for the approach bridges

totalling approximately 65,000 tons were

manufactured in Spain on a large work site area in

Cdiz. Here the steel trusses were assembled and

painted in elements with the full span length

(generally 140 m). Also in Cdiz the upper roadway slab was cast, and for this purpose the

subcontractor had built a huge covered workshop with a roof spanning 150 m so that the steel

trusses could be moved in and out sideways. Furthermore, the workshop had large air condition

plants installed to reduce the temperature rise during concrete hardening.

From Cdiz the approach span girders were

transported in pairs to the work site area in Malm

on large barges each capable of carrying two

prefabricated spans each weighing almost 5000

tons,

At the work site area in Malm the precast concrete

trough girders were added at the lower deck before

the full span unit was transported to its final

location.

Every second week two 140 m girders arrived in

Malm and were subsequently erected by Svanen.

Consequently, the bridge grew in average by 20 m

per day throughout the erection period.

3.2 Main bridge

With the main bridge forming a relatively small part (approx. 15%) of the total bridge length it wasobvious that a structural solution should be sought where the approach spans (comprising

Fig. 16: Node of the main truss

Fig. 17: Truss at the storage area in Malm.

Fig. 18: Covered workshop at the work site

Fig. 19: Svanen with 140 m truss element

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continuous trusses) could continue into the main bridge without a complete change of structural

system and materials, and without an abrupt visual transition. Also the strict requirements regarding

strength and stiffness imposed by the passage of both heavy freight trains and high speed passenger

trains proved to have a strong influence on the design of the main bridge with its 490 m main span

the longest for any cable-stayed bridge carrying both road and railway traffic.

All these requirements clearly pointed towards a cable-stayed main span with a girder composed of

two vertical steel trusses and an upper concrete deck - as in the approach spans of the bridge. The

demand for a high degree of rigidity led to a harp-shaped cable system with relatively steep cables

and intermediate support in the side spans.

Fig. 19: Elevation of cable-stayed spans

To facilitate the anchoring of the stay

cables at the deck level it was decided

to change the truss geometry in the

cable supported regions. Thus, the

geometry of the approach spans where

all diagonals have the same length ismodified so that the two diagonals

leading to each node have different

inclinations and lengths. By this it was

achieved that the long diagonals

became parallel to the stay cables.

With the vertical trusses positioned in

the same transverse distance as in the

approach spans special structural

elements are required to transfer the

load to the cable system. Furthermore,the selection of a harp shaped cable

system and free-standing pylons above

the bridge deck imposed a distance of

31.5 m between the cable planes.

With the chosen lateral position of the vertical cable planes (imposed by the demand to have

uniform compression across the pylon cross sections from vertical load) the distance between the

cable anchorages at the girder level became 7 m larger than the width of the roadway. The load

transfer from the main trusses to the stay cables is, therefore, established by adding triangular

brackets (outriggers) in the plane of the long diagonals. At the end of each outrigger two anchor

tubes are positioned to give support to the sockets of the double stay cable.

Fig. 20: Adjustment of truss geometry from approachspan to main span

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Besides the adjusted truss geometry and

the addition of outriggers the main span

girder also deviates from the approach

spans by having a lower railway deck

made as a shallow box girder in steel.

This was chosen to reduce the dead loadand improve the capacity to transmit the

large positive moments at midspan.

The triangular brackets (outriggers)

and the adjusted truss geometry give the

main span a quite unique appearance

and at the same time it exhibits an

honest structure where nothing is done

to hide the flow of forces from the two

decks to the stay cables and further to

the 203.5 m high pylons.

The steel structure of the main span

girder was fabricated in Sweden at a

shipyard in Karlskrona. The steel grade

applied was generally S 420 N with a

yield stress of 420 MPa. After

completion of erection units with a

length of 140 m or 120 m the steel

structure was transported to the work

site area in Malm where the upper

concrete slab was cast.

During erection the girder of the main

span was supported on the pylon cross

beams, on the permanent piers in the

side span and on temporary piers in the

main span. The temporary piers were

allowed due to the fact that the

navigation channel were to be relocated

after completion of the main span

erection, and consequently no shipping

took place through the main span until

after completion of the superstructure.

After erecting the superstructure from

the transition pier at the end of the side

spans to midspan the cable erection was initiated and subsequently the load was transferred from

the temporary piers to the cable system.

With the chosen procedure comprising temporary piers the 490 m long main span could be erected

as four girder units with the concrete slab already in place as it was cast at the work site area. Only

Fig. 21: The main span girder with outriggers at thework site area

Fig. 22: Deck cross section in the cable-stayed spans

Fig. 23: Partly erected main span on temporary piers

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relatively small portions of the deck slab at the joints between the erection units had to be cast on

site.

The stay cables of the resund Bridge

contains approximately 70 seven-wire strands

inside a HDPE tube with an external diameterof 250 mm. To counteract rain-wind induced

vibrations the surface of the tubes were made

with a double helical spiral 2 mm thick.

However, this modest measure did not prove

sufficient to suppress the vibrations and

especially in case of sleet large oscillations of

the longest stays were observed. Further

measures in the form of dampers at the stay

anchorages and on the free length then had to

be taken.

4. Femern Belt Bridge

Only two years elapsed from the opening of the Great Belt Bridge to the opening of the resund

Bridge but almost twenty years will pass before the third if the large bridges, Femern Belt Bridge,

will be ready to carry the traffic from Sweden, Norway and Eastern Denmark on the most direct

route to Central Europe. The distance from Copenhagen to Hamburg will be shortened by 150 km

when travelling via Femern in stead of via Great Belt.

The final treaty between Denmark and Germany to build a bridge across the Femern Belt was

signed on 3 September 2008. It was agreed that the bridge from coast to coast should be designed,

financed and supervised by a Danish owned bridge authority whereas the approaches on land should

be handled by each of the two countries. The preferred solution was indicated to be a high level

bridge with a multi-span cable-stayed bridge across the international navigation channel. However,

it was also stated that an immersed tunnel should be further investigated for comparison.

4.1 Feasibility study 1999A feasibility study of the Femern Link was performed at the end of the 1990.s. It comprised traffic

forecast, environmental issues, geotechnical investigations for a number of technical solutions.

In the technical studies both immersed and bored tunnels were investigated for rail only as well as

for rail+road. Bridges were studied only for combined road and railway traffic with a dual-two lane

motorway and a double track railway.

The bridge proposals were in their main design features similar to the resund Bridge, i.e. with a

double deck truss carrying the two railway tracks on the lower level and the motorway on the upper

level. The depth of the truss was, however, increased to 15 m to allow the approach bridges to have

spans of 240 m.

Across the navigation channel two solutions were studied, a multi-span cable-stayed bridge and a

suspension bridge.

Fig. 24: Polyurethane tubes used as casings

around the bundles of seven-wire strands

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The cable-stayed bridge was designed with three

724 m main spans to allow one-way ship traffic in

two navigation channels each with a horizontal

clearance of 700 m.

The suspension bridge was designed with a 1752 mmain span and 588 m side spans.

The cost estimates clearly pointed towards the

cable-stayed option and after the conclusion of the

Feasibility Study it was decided that the primary

solution for the Femern Belt Link should be the

bridge option with cable-stayed main spans and as a

secondary solution an immersed tunnel.

More recently it has been questioned by some navigational authorities whether the cable-stayed

bridge will give sufficient safety as shipmasters without experience in navigating through the bridgemight be confused when approaching it and then select the central span in stead of the assumed

outer starboard span. Also, it is realised that the nearest anchor pier in the side spans of the cable-

stayed bridge would carry a special risk in relation to ship collision as the distance from the center

of the navigation span to the nearest anchor pier is only 640 m .

Fig. 26: Suspension bridge from the Femern Belt Link Feasibility Study 1999

It is, therefore, likely that the bridge consultants will reconsider the design of the navigation spans

in the Femern Belt, and maybe also reinvestigate a suspension bridge main span.

4.2 Ongoing investigationsTo give the best basis for the designers of the reference design to be tendered a number of

investigations have already been initiated.

Extensive environmental investigations have started to form the basis for the Environmental Impact

Assessment (Hydrography, Marine Biology, Approaches on land, etc.).

Geotechnical investigations of soil conditions is expected to continue until the end of 2011 within a

total budget of 40 million Euro.

Investigations into navigational safety are about to be concluded and will form a decisive basis for

the final choice of main span and approach span configurations.

With the unexpected appearance of individual cable vibrations in the resund Bridge a thorough

study of cable vibrations under wind, rain and frost conditions has been initiated at the Department

Fig. 25: Cable-stayed bridge from theFemern Belt Link Feasibility Study 1999

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of Civil Engineering, technical University of Denmark As part of this study a Climatic Wind

Tunnel will be installed at Force Technology in Denmark.

The specifications for the Femern Climatic Wind Tunnel:

- 20m x 8m closed-circuit- 25 m/sec mean wind velocity (min) with turbulence grid and flaps at -5

OC

- 40 m/sec mean velocity (min) without cooling elements

- Water spray capabilities (simulated rain) and water-proofing

- 2m2m section minimum to allow for a maximum of 10% blockage on a 200 mm wide

cable or bridge section

- Consistency of flow characteristics for both smooth and turbulent flow

- Full turbulence spectrum (within reason) achieved through some form of flaps

(turbulence generators)

- Approx. 1 MW tunnel power consumption

The total expected cost for the Climatic Wind Tunnel is approximately 1.3 Million Euro.

The actual construction of the Femern Belt Link is planned to start in 2012 with a completion in

2018.

5. References

[1] GIMSING, NIELS J. (editor), The Great Belt Publicartions: West Bridge, A/S Great Belt,

Copenhagen, 1998

[2] GIMSING, NIELS J. (editor), The Great Belt Publicartions: East Bridge, A/S Great Belt,

Copenhagen, 1998

[3] GIMSING, NIELS J., Cable Supported Bridges Concept and Design, Wiley,

Chichester, U.K., 1998.

[4] GIMSING, NIELS J. (editor), The resund Technical Publications:

THE BRIDGE, resundsbro konsortiet, Copenhagen, 2000.

[5] Trafikministeriet, Femer Blt-Forbindelsen, Forundersgelser Resumerapport (Femern

Belt Link. Feasibility Study Summarising Report), Trafikministeriet, Copenhagen, 1999.