anónimo - footbridge awards 2008

Footbridge Awards 2008 - Final 13/6/08 15:17

www . l a p - c o n s u l t . c om

50 years of experience in all aspects of structural engineering

creative and innovative designs

competitive contractor‘s opinions

state-of-the-art detailed designs

checking of designs by others

supervision on site

Tri-Countries Bridge across Rhine River, GermanyWinner Footbridge Award 2008 Category Technology-Long SpanHighly Commended Aesthetics-Long Span


CONTENTS

IntroductionBridge engineers are constantly pushing the boundaries of structural engineering and striving

to achieve the ultimate in aesthetics; nowhere is this more true than in footbridge design.The winners of the Footbridge Awards 2008 come from around the globe, proving that gooddesign is inherent in the industry worldwide.

The number and quality of entries to this year’s awards made judging very difficult. Our expertpanel gave careful consideration to the aesthetic and technical achievements of all the projectssubmitted, before identifying the winning schemes and awarding highly-commended status tothose that came very close. In the technical medium span category it proved impossible tochoose between two outstanding projects, and we compromised by recognising them as jointwinners.

I would like to take this opportunity to congratulate our winning teams, finalists and allentrants for their efforts in maintaining the industry’s highest standards, and to thank our panelof expert judges for taking the time to review and comment on a substantial quantity ofinformation.

Helena Russell

Published by:Bridge design & engineering32 Vauxhall Bridge Road, London SW1V 2SS, UKTel: +44 20 7973 6400ISDN: +44 20 7931 0833Website: www.bridgeweb.comEditor: Helena RussellTel: +44 20 7973 4697Fax: +44 20 7973 4797Email: [email protected] sales manager: Lisa BentleyTel: +44 20 7973 4698 Fax: +44 20 7233 5053Email: [email protected]

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Sales director Emma SabinProduction director Linda AldersonCirculation manager Maggie SpillaneDesigner Inderpal S. PattiProduction Corrine SavageManaging director Graham Bond

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Cover picture: Tri-Countries Bridge, Weil am Rhein

4 WINNER Simone de Beauvoir BridgeParisian bridge with literary leanings winsan aesthetics award

6 Aesthetics: highly commended Tri-countries Bridge and Newport Footbridge are also recognised in the long span category

7 WINNER Svratka River BridgeA new structural form in Brno takes theprize in the medium span category

8 The WingAlmere’s footbridge flies effortlessly into the highly-commended spot

9 Living BridgeA new link for Limerick University inIreland is highly commended

10 WINNER Borgo Tossignano FootbridgeA new addition to an old bridge hits thespot in the short span aesthetics category

11 Aesthetics: Highly commendedKew Gardens, UK and Drachten, The Netherlands are highly commended

12 WINNER Tri-Countries BridgeLinking communities, it is a winner in the technical long span category

13 Technical: highly commendedNessebridge, Germany and Passerelle 2006, Italy win recognition

14 JOINT WINNER Studenci FootbridgeLink in Slovenia shows innovation in the technical medium span category

15 JOINT WINNER Svratka River BridgeA second prize for this Czech winner

16 Technical: highly commended Recognition for Macintosh IslandFootbridge and Oosterdoks Swingbridge

17 WINNER Plettenberg Bay BridgeSouth African winner in the technicalshort span category

18 Technical: highly commendedBaden-Baden and Papakura are recognised

JudgesDr Wasoodev Hoorpah is a consulting engineer specialising insteel structures and bridge design, and chaired the workinggroup on dynamics of footbridges at AFGC in France. He iseditor of a footbridge magazine.

Dr Alessandra Zambrano is a consulting engineer andprofessor at the Second University of Naples where she teachestheory and design of bridges.

João Fonseca is partner at consulting engineer Encil -Projectos e Estudos de Engenharia Civil, and associateprofessor at the University of Beira Interior in Portugal where hespecialises in structural engineering.

33www.bridgeweb.com


The Simone de Beauvoir footbridge seems to float in theair, carried along by its own momentum, relying on its

own audacity. Grace is conferred by its physical lightness,and elegance by its apparent technical simplicity. It is anevent in itself: those using it are less motivated by a need tocross the river than by the pleasure of being there tocontemplate the river, the passing of time, and thelandscape that it reveals and rearranges.

The bridge is formed by wave shapes which are intendedto give it a syncopated rhythm, and carries pedestrians notonly over the river, but also over the riverside roadways oneach side. On the right bank is a chaotic expanse and, onthe left bank, is a more formal avenue which runs below thesteps leading up to France’s National Library.

It rests on the river banks, relaxed and open on one side,restricted on the other, before its symmetrical launch, whenthe structure is freed from its asymmetrical departurepoints. Over its 194m length, an arch and a beam cross inthe air above the water, each linking the two levels of thebanks; at the top, the National Library esplanade and gardenterrace with, lower down, the two quaysides. Ramps andstairs lead to the river banks.

Approaching it, pedestrians discover the amplitude of thebridge’s bows – it initially resembles a rope bridge, a gentlerollercoaster that invites users to cross the river. They canfeel the structure vibrate, it is flexible rather than rigid andwhen pedestrians stop in the middle, it seems to shiverunderfoot.

Architect Dietmar Feichtinger wanted it to be a livingentity; he intended to prompt the viewer to appreciate thebridge as a work of art, rather than just a feat ofengineering. The footbridge is also a hub, not only becauseit links two river banks and two districts that until now had

been divided, nor because it provides a new choice ofroutes, but rather because it creates an equilibrium. But thisequilibrium is not static or frozen, it is dynamic, being in a

state of constant change that depends on the loads, windsand temperature. Its elastic and flexible equilibrium is notthe result of an established order governed by constraintsdemanding the use of excessive measures to hold it inposition. Rather than being like an oak tree, constrained andrigid, it is intended to be like a reed, free, fluid and reactive.

While the footbridge uses few materials, they assist oneanother, with traction compensating for compression andtorque balancing torsion. The perfect solidarity of theelements, their shared workload and stresses offer a way ofadapting to the world with its difficulties and adversities. Thefootbridge gives physical form to the flows developed for itsdesign and resembles a suspended wave-like movement.There is no design affectation nor redundant details. Themetal elements are welded together, nothing is bolted to thestructure, with the exception of the oak floor planking.

All steel parts are made of steel S355 (N or M), of qualityL or K2G3 according to their thickness, with some beingclass Z. The entire steel construction is protected againstcorrosion and painted metallic grey. All connections in themain structure are welded, with the exception of thespherical bearings of the ‘boomerangs’ and the connectionof the main bridge with the approach bridges.

All welding work to the central lens was carried out in thefabrication yard, while the side elements and theconnections at the points of intersection were made on site.

The decks are clad in striated oak, with non-slip inserts,and the gaps between the balustrades are made of stainlesssteel nets stretched vertically between the extrudedaluminium handrail and a guiding rod at the bottom. The netis transparent but sufficiently visible to convey a good senseof safety, and the lighting is integrated into the handrails,emphasising the silhouette of the bridge.

Aesthetics long span: WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Mairie De Paris

PPrriinncciippaall ddeessiiggnneerr:: Dietmar Feichtinger Architectes

SSttrruuccttuurraall eennggiinneeeerr:: RFR Engineers

PPrriinncciippaall ccoonnttrraaccttoorr:: Eiffel Construction Métallique

OOppeenneedd:: July 2006

Judges’ comment“This is bold architecture which fits very well into its green,urban surroundings”

“The architect’s solution provides an appropriate landmark forthis high-profile site”

SIMONE DE BEAUVOIRFOOTBRIDGE, PARIS, FRANCE

WINNER

44 www.bridgeweb.com


66

Aesthetics long span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Welsh Assembly Government

PPrriinncciippaall ddeessiiggnneerr:: Atkins

AArrcchhiitteecctt:: Grimshaw

PPrriinncciippaall ccoonnttrraaccttoorr:: Alfred McAlpine Project Services

SStteeeell ffaabbrriiccaattoorr//eerreeccttoorr:: Rowecord Engineering

Aesthetics long span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: City of Weil Am Rhein

SSttrruuccttuurraall eennggiinneeeerr:: Leonhardt, Andrä & Partner

AArrcchhiitteecctt:: Dietmar Feichtinger Architectes

PPrriinncciippaall ccoonnttrraaccttoorr:: Max Bögl

LLaauunncchhiinngg ssuubbccoonnttrraaccttoorr:: Saarens

Newport’s new footbridge links the east bank of the Usk to the city’s commercial centreon the west. The dramatic crane structure is a symbolic link to the site’s earlier use as

trading wharves, and creates a strong landmark on the city skyline, drawing attention to ariver that is hidden from much of the city centre. These dramatic aesthetics are achievedby placing the main supports on one bank of the river, and as a result, kept most of theworks away from the east bank’s residential areas. An existing car park on the west bankwas used as a flat construction site. The crane structure avoided any impact on the ecologyof the river, and by minimising temporary works, maximised effort and expenditure on thepermanent bridge. Design of the eastern abutment was modified to provide access alongthe riverbank for otters and the lighting plan was adapted to avoid lights shining directlyinto the water as this could disrupt fish migration. Four masts anchored on the west banksupport the 135m-long bridge deck. They are stayed by two 120mm diameter cableswhich also transfer the deck loads to ground level. The tallest element is the back mast,67m above ground level. The entire steelwork weighs 850t; it was fabricated by Rowecord,assembled on site in January 2006, and installed in May of the same year.

This 248m-long footbridge over the River Rhine connects the residents of threecommunities, and three countries. It links the French town of Huningue directly to the

town of Weil am Rhein in Germany, and is very close to the Swiss border.The footbridge lies along the axis of two main roads; both the Hauptstrasse in Weil am

Rhein and the Rue de France in Huningue, France, are on the same alignment. Toemphasise this visual connection between the two countries, the cross-section of thefootbridge was made asymmetrical in order not to block the view along this axis.

A double hexagonal tubular steel arch is the main support element of the bridge, and onthe south side, another single arch is inclined against it. The details of the design such asthe supports close to the river banks, the widening of the slowly rising ramps, and theparapets consisting of cable-suspended steel-nets leave the sight of the river undisturbedand enable the bridge to blend into the landscape. The entire main bridge with a length of248m was assembled several hundred metres north of the final location, then floated intoplace. As the shipping route allows a closure of maximum 24 hours, the process of floatingthe bridge and putting it on temporary support jacks had to be finished within this time slot.

“The separationof the deck

and mastalignments is

pleasing, as isthe delicacy of

the cranestructure”

“The bridge offersa unifying

gesture,delivered with

remarkableslenderness and

transparency”

Judges’ comment Judges’ comment

NEWPORT CITY FOOTBRIDGE,NEWPORT, WALES

TRI-COUNTRIES BRIDGE, WEIL AM RHEIN/HUNINGUE, GERMANY/FRANCE

www.bridgeweb.com


The designers of this new footbridge tried to find astructural form that was inherent to the bridge site and

which best fulfilled the function of bridging the site. It is aclean, simple structure made of structural elements on ahuman scale; a structure that expresses - through itsstructural system and material used - the progress inscience and technology.

The deck of the bridge is formed by a stress ribbon thatis supported by a flat arch - since both the stress ribbonand the arch are fixed in the same abutments, the structureforms a self-anchored system that stresses the footings byvertical forces only. Both stress ribbon and arch wereassembled using segments made of high strengthconcrete, and were erected without using temporarysupport. This is the first structure of its type to be built.

The bridge connects the newly-developed SpielberkOffice Centre with the historic city centre, and is situated inthe vicinity of a new international hotel and a prestigiousoffice area. Close by is an old multi-span arch bridge withpiers in the river, so it was obvious that the new bridgeshould also be formed by an arch structure. The designerswanted to build a span without any supports in the riverbed, but due to poor geotechnical conditions, a traditionalarch structure with a large horizontal force would havebeen too expensive. The self-anchored stress ribbon andarch structure was a logical solution to this problem, andthe smooth curves that are characteristic for stress ribbonstructures allowed a soft connection between the bridgedeck and the banks.

Since the riverbanks are formed by old stone walls, theend abutments are situated beyond these walls. Theabutments are supported by pairs of drilled shafts; the rearshafts are stressed by tension forces, the front shafts arestressed by compression forces. These pairs of forcesbalance the tension and compression forces originating inthe stress ribbon and arch.

The arch span has a length of 42.9m and a rise of2.65m, giving a rise to span ratio of 1/16.19. The arch is

formed by two legs whose separation is variable and whichmerge at the arch springings. The 43.5m-long stress-ribbon is assembled of 1.5m-long segments, and in themiddle portion of the bridge it is supported by low spandrelwalls. The stress ribbon is carried and prestressed by fourinternal tendons of 12, 15mm-diameter monostrandsgrouted in PE ducts. The segments have a variable depthwith a curved soffit. Both the stress-ribbon and the arch aremade from high-strength concrete which has acharacteristic strength of 80MPa.

The arch was assembled from two arch segmentstemporarily suspended on erection cables anchored at theend abutments. Before the mid-span joint was cast, thelength of the erection cables was adjusted, and in this waythe effects of deformations of the shafts were eliminated.Once this had been carried out, the erection cables werereplaced by external cables that tie the abutments together.The segments were then placed on the arch spandrel wallsand on the external cables. Subsequently, the internal

tendons were pulled through the ducts and tensioned andfinally the external tendons were removed. In this way, therequired geometry of the deck was obtained. After castingthe joints between the deck segments, the cables weretensioned up to the design stress and, as a result, the deckwas prestressed.

The structural solution was developed on the basis ofvery detailed static and dynamic analyses. The staticfunction and quality of the workmanship were checked byloading tests, during which trucks were brought onto thebridge – in one test they were loaded on the full length ofthe deck, and in the other, on half the length of the deck.The bridge is very stiff hence there is no risk of usersfeeling uncomfortable vibrations when they are crossing orstanding on the bridge.

The construction of the bridge started in February andwas completed in September 2007; it cost just €530,000to build, and was well-received by the public when itopened.

Aesthetics medium span: WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: CTP Invest

AArrcchhiitteecctt:: Studio Acht

SSttrruuccttuurraall eennggiinneeeerr:: Strasky, Husty & Partners

PPrriinncciippaall ccoonnttrraaccttoorr:: Skanska DS

OOppeenneedd:: October 2007

Judges’ comment“Nice looking and so discreet in its simplicity”

“Simple and slender, this bridge is not only a cost-effective solution,it is modest in its intentions”

SVRATKA RIVER BRIDGE, BRNO,CZECH REPUBLIC

/

WINNER

77www.bridgeweb.com


www.bridgeweb.com88

The municipality of Almere wanted an elegant, lightbridge to cross a lake measuring 60m by 300m in the

new residential area of Oostvaardersbuurt in Almere. Thebridge lies on an important alignment which carries apedestrian and cycle route between the centre of the cityand the suburbs. As it crosses the water, the alignmentcurves, and consequently the bridge follows this samecurve. Verburg Hoogendijk Architects designed a structurewith two basic components; the actual support structure isin the shape of a curved wing that glides over the water andis supported by two columns. The second component

consists of two small substructures that connect the mainbridge to the two concrete embankments.

The main structure is intended to mimic the wing of anaeroplane, with ribs on the inside working together as onestructure with the skin of the wing on the outside. Thebridge designed by VHA performs in exactly the sameway. The steel ribs on the inside are connected with theouter steel skin and together they form a strong structureto support the bridge deck.

The concrete structures on land are set back so thewaters edge is kept free of obstacles, allowing flora and

fauna to migrate easily along the water’s edge. Thelength of the bridge is about 100m, with an actual spanof 45m and width of 4m. The various components of thebridge all come together through the fact that they arecarefully detailed and a great deal of effort went intoresolving the point at which the bridge deck meets thegreen bank. The combination of the steel wing-structure,the stainless steel railing, the steel deck and the five lightmasts give the bridge its elegant and outstandingappearance, emphasising the bond between techniqueand tradition.

Judges’ comment“Its elegant profile blends perfectly blends with the flat countryside”

“This low-lying, slender form seems to create a continuousconnection between the two sides of the water”

Aesthetics medium span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Municipality Almere

AArrcchhiitteecctt:: Verburg Hoogendijk Architects

SSttrruuccttuurraall eennggiinneeeerr:: ABT Delft

PPrriinncciippaall ccoonnttrraaccttoorr:: BRS Staalwerken

OOppeenneedd:: September 2005

THE WING, ALMERE, THE NETHERLANDS

Creativity – Knowledge – Experience – Hard workFrom small pedestrian bridges to large scale projects

Pedestrian Bridge across the Svratka River in Brno

Bridge across the Odra River, Motorway D47

Strasky, Husty and Partners, Ltd.Consulting Engineers

Bohunicka 50, 619 00 Brno, Czech Republicwww.shp.eu


www.bridgeweb.com 99

Linking the established and developing campuses of theUniversity of Limerick, the ‘Living Bridge’ creates a new

journey through the hidden natural environment of the RiverShannon. The bridge provides a new connection between thecampus on the south side of the River Shannon and theuniversity’s developing annexe on the north.

At this point the Shannon is wide and shallow, fragmentedby woodland growth and with extensive flood plains. With amajor new performing arts centre at the northern end of thebridge, there is a large footfall over the crossing, and as a‘living bridge’ the intention is that it should become inhabited

as a place for informal meetings, exhibits and performances.The bridge sweeps across the Shannon on a wide curve in

six spans between strategically located supports on theriverbanks, wooded islands and pool edges. The impression isboth of a single crossing and also of a series of bridgesjumping from pier to pier like stepping stones. This alternatingrhythm of bridge and island is reinforced in the construction,with lightweight bridge structures connecting the solid landingpiers. At each end the deck is seen disappearing into thelandscape without sight of the destination, and the journeytemporarily encloses pedestrians in the natural environment

of the river corridor, celebrating it as a hidden delight. Thedeck widens at each landing pier to create a gathering spaceor refuge furnished with benches and shelters.

The lines of the bridge are visually reinforced by nightwhen the slender deck edge is illuminated by lights.Additional lighting units in the parapet posts impart arhythmic tempo to the crossing and provide a safely litenvironment for the bridge user. The 350m-long bridge isformed of six 44m spans between steel ‘tetrapod’ supports.The bridge sections are supported from below deck level bya pair of cable trusses.

Judges’ comment“A stunning structure which, despite its size, fits well in thesurroundings”

“The repetitive inclination of the parapet and main struts is pleasing”

UNIVERSITY OFLIMERICK ‘LIVING

BRIDGE’, LIMERICK, IRELAND

Aesthetics medium span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: University of Limerick

AArrcchhiitteecctt:: Wilkinson Eyre Architects

SSttrruuccttuurraall eennggiinneeeerr:: Arup

PPrriinncciippaall ccoonnttrraaccttoorr:: Eiffel UK

OOppeenneedd:: November 2007

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The process of adapting bridges with historic andarchitectural significance for modern requirements is an

issue of major importance. Such adaptations demand thatarchitects and engineers have a thorough understanding ofthe complex issues that have to be resolved to achieve asolution that is both valid in form and responds to theenvironmental and functional needs of the location. Thistype of intervention is only possible if the chosen solutionrespects the existing structure and also capitalises on itsarchitectural, environmental and visual features. Generallyspeaking, in order to preserve the historic and architecturalfeatures of a bridge, the best approach is to select formsand materials that are distinct from the older architecturalstructure. This conserves the role of the historical structureas fully as possible, and creates a result in which the oldand the new integrate on a functional level.

The cyclist and pedestrian bridge in the town of BorgoTossignano is a good example of the functional adaptationof an older bridge which dates back to 1945 and carries alocal road that runs from north to south west, linking thethree provinces of Ferrara, Bologna and Florence.

The old bridge across the river Santerno is part of anextensive geographical context characterised by amultitude of small towns and villages scattered over theadjacent land and its bordering foothills. Today the bridge isa nodal point not only for inter-provincial and regionalcommunications but for movement within the municipalityitself. Under the high volume of vehicular traffic and thecontinuous transit of pedestrians and cyclists seen today,the old bridge is inadequate not only from the static andfunctional points of view but in terms of road safety too,since its physical limitations make it impossible toguarantee the safety of all users. The solution to thisproblem was the construction of a new bridge alongside theexisting structure, to separate pedestrians and cyclists fromvehicular traffic.

Bearing in mind the major historic and architecturalsignificance of the original bridge, the decision was madeto adopt a design solution that would conserve the oldbridge and emphasise those features that make it so

interesting from an architectural, environmental and visualpoint of view. The work modifies the original width to makeit compatible with the needs of present-day vehicular,cyclist and pedestrian traffic, but enhances the historicalstructure within its natural context through sensitive staticadaptation and delicate interventions that adapt the oldbridge to meet modern needs without spoiling its originalappearance, an image that very much forms part of thecollective memory of the local population.

The work was completed by erecting a steel structureconsisting of a series of arches, reflecting the design of theoriginal bridge. This is secured to the old bridge wall andsupports a wooden platform that carries cyclists andpedestrians alongside the existing roadway.

Vertical loads are distributed by the wooden platform andtransmitted to the ground via a coordinated sequence ofsteel, T-section cross-beams at intervals of 700mm. On oneside, these are secured to the face of the existing bridge andon the other side they rest on tubular profiles which are300mm in diameter and 7.1mm thick, themselvessupported by steel arches. The arches transmit the verticalloads via tubular profiles of 508mm diameter and 12.5mmthick down to the tops of the existing piles, making use oftheir angle to the vertical. The upper cross-beams thatsupport the platform fulfil the connection function necessaryto avoid tipping. Stability in the longitudinal plane is providedby a longitudinal member which runs along the centre lineof the platform and consists of two coupled HEB profiles.

1100

BORGOTOSSIGNANOFOOTBRIDGEBOLOGNA,ITALY

Aesthetics short span: WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Provincia di Bologna

PPrriinncciippaall ddeessiiggnneerr:: Progeest

PPrriinncciippaall ccoonnttrraaccttoorr:: A Guidi

OOppeenneedd:: June 2006

Judges’ comment“A very nice combination of old and new”

“The solution respects the original structure thoroughly, and givesa pleasing aesthetic result”

www.bridgeweb.com

WINNER


The Sackler Crossing plots a serpentine path over thewater, its constantly curving route yielding its secrets

gradually. The deck is set the minimum possible distancefrom the lake’s surface, allowing visitors to feel they aretaking a walk across the water, and this sense is enhancedby views of the lake between the deck treads and by thenear invisibility of the supporting structure.

Rhythmic bands of dark granite form the deck, whilebronze uprights emerge from the gaps between them to actas simple balusters, the top of each slender piececontoured to fit comfortably in the hand. Viewed end on, thebalusters appear solid, but from the side this solidity

fragments, allowing views through and affording thestructure a pleasing material ambiguity.

The structure supporting the 70m-long crossing wasdesigned to be sleek and unobtrusive by using a slendersteel support framework. Driven tubular piles in the lakebed extend above water level to act as discreet centralsupports to the framework at 8m intervals.

The steel framework forming the deck consists of agrillage of longitudinal hollow sections and slendertransverse ribs - these ribs are not visible from above,having been designed to fit between gaps in the graniteplanks. The deck units were curved in plan to enhance

interest and each section was hot-dip galvanised andpainted for long term durability.

The 564 granite sleepers forming the walkway rest onpads above the steelwork and are spaced apart to permitthe deck to drain and users of the crossing to appreciatethe water below. A series of full-scale mock-ups wascommissioned to test and refine the proposed design, andthis process was invaluable in communicating the client’srequirements to contractors tendering for the project.

The low maintenance requirements of the materialschosen meant that the whole life costs of the structurecould be minimised.

Judges’ comment“The balustrade and the curve of the structure are verypleasing to the user”

Aesthetics short span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Royal Botanic Gardens, Kew

PPrriinncciippaall ddeessiiggnneerr:: John Pawson

SSttrruuccttuurraall eennggiinneeeerr:: Buro Happold

PPrriinncciippaall ccoonnttrraaccttoorr:: Balfour Beatty

OOppeenneedd:: May 2006

The Drachten Wheel concept was developed in responseto the need to create a landmark, as well as providing a

link to a new business park on the other side of themotorway from the town centre. The bridge carriespedestrians and cyclists over the A7 motorway and a 15m-wide drainage canal. The designers reached the final formquite quickly, but the reasoning was not obvious. Becauseof plans for future road widening, the pier was placed inbetween the two road carriageways.

Often the deck of a cable-stayed bridge appears to becramped by the legs of its tower – so why not open out the

legs to make clear space all around the deck? In this waythe cable planes become interesting, and the towerbecomes a tall ellipse which is tilted, because of the plancurvature of the deck. Drivers approaching on themotorway see it as a traditional upright tower – only as theviewer gets closer does the three-dimensional aspectbecome clear.

In the Netherlands the design impact force on the bridgedeck from an overheight vehicle is 2MN, which is very high.The circular tubes that make up the edge members of thedeck offered a solution to this – they could be filled with

concrete where they pass over the highway. Robust detailswere also required at the supports, and the solution waswhat became known as the crescent beam. By offsettingthe bearings some way below the deck, they were able toabsorb thermal strains with small rotations, and rugged pinbearings could be used in place of sliding ones. Thecrescent detail is also a particularly pleasing example of theseparation of parts – introducing some space and a gently-curved member where the deck meets the columns.

The bridge, its approaches and associated landscapingwere built for €2.4 million.

Judges’ comment“A creative use of the spoked wheel concept, and at areasonable cost”

Aesthetics short span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Gemeente Smallingerland

PPrriinncciippaall ddeessiiggnneerr:: Arup

SSttrruuccttuurraall eennggiinneeeerr ((ccoonnccrreettee)) :: Grontmij

PPrriinncciippaall ccoonnttrraaccttoorr:: Van Spijkerbouw

OOppeenneedd:: July 2006

1111

THE DRACHTENWHEEL,

DRACHTEN, THENETHERLANDS

SACKLERCROSSING,

LONDON, UK

www.bridgeweb.com


This new footbridge connects Germany and Franceacross the Rhine River with a record-breaking main

span of almost 230m, and a total length of 248m from oneside to the other. The bridge is extraordinary due to its size,its low cost and the particular attention that was paid to theissue of dynamics in the structure.

In July 2001 the city of Weil am Rhein and theCommunauté des trois communes announced a competitionto construct a pedestrian and cyclist bridge across the RiverRhine, to improve the infrastructure of the region and cross-community relations. It was opened in March 2007 and is inthe south west corner of Germany, close to the Swiss border,hence the name of the bridge.

The basic criteria for the design of the bridge was anavigation clearance envelope of 7.8m high by 155m wide.To reduce the risk of ship collision even further, piers in theRhine River were avoided. The steel arch bridge has a totallength of 248m and a main span of 229.4m, the longest inthe world for pedestrian bridges. There are ramps and stairson both sides of the main bridge, and a lift in Huningue offersadditional access for wheelchairs and so on.

The alignment of the structure is designed to tie-in with,but not obstruct the views along, the main roads on each sideof the river. The Hauptstrasse in Weil am Rhein, Germany, andthe Rue de France in Huningue, France, are situated on thesame axis. To emphasise this highly symbolic and visualconnection between the two countries, the footbridge isaligned with the axis but its cross-section is made asymmetricin order not to obstruct the view along the avenue.

The structural design of the bridge is a response to thisparticular situation, which in turn creates a technicalchallenge. The main structural elements of the bridge are avertical, double hexagonal tubular steel arch on the northside, and an inclined, circular hollow section arch on thesouth side. The visual scope of the structure is widened bythis cross-sectional arrangement.

Other details of the design, such as having the supportsclose to the river banks, incorporating a widening of theslowly-rising ramps, and using cable-suspended steel meshfor the railings, leave the sight of the river undisturbed and

enable the bridge to blend into the landscape somewhat,despite its size.

The complex details are carefully designed with regard todurability and aesthetics. The joints of the arches are builtusing cast steel nodes, in order to avoid the use of gussetplates. This support arrangement is fixed for longitudinaldisplacement, but restrains horizontal rotations.

The quality of design and construction of the complexdetails is demonstrated, for example, in the base of the archon the west side of the river, for which the latest researchand development results for cast steel nodes were used.

The inclined locked-coil rope hangers connecting theorthotropic deck with the arch, use open sockets whichmake it possible to adjust the cable lengths.

In order to make efficient use of materials and to saveenergy, the amount of structural steel was minimised to1,020t, or about 120kg/m2. The cost of the whole projectwas just €9 million, or about €1,050/m2, thus providinggood value for money. To the client’s satisfaction, thebudget was not exceeded and if the bridge behaves as

predicted, the robust design will contribute to keeping thelife-cycle costs low.

The main bridge was assembled to its entire length of248m at a construction site a few hundred metres to thenorth of the final location, then shifted onto pontoons andfloated into position. The team was only allowed to closethe shipping route for a maximum of 24 hours, hence theprocess of floating the bridge and putting it on temporarysupport jacks had to be finished within this time slot.

Before the opening of the bridge, vibration tests wereperformed to check its dynamic behaviour, with thecooperation of about 1,000 people from both communities.

They walked in step across the bridge, under thedirection of the engineers, to check the lateral vibrations ofthe structure.

The testing revealed that the critical lateral vibrations areonly activated when more than 500 people cross the bridgeat a walking speed of at least 5.8km/h. The probability ofthis scenario is very low, consequently the city councilsdecided not to install dampers.

TRI-COUNTRIESBRIDGE, WEILAM RHEIN/HUNINGUE,GERMANY/FRANCE

1122

Technical long span: WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: City of Weil Am Rhein

SSttrruuccttuurraall eennggiinneeeerr:: Leonhardt, Andrä & Partner

AArrcchhiitteecctt:: Dietmar Feichtinger Architectes

PPrriinncciippaall ccoonnttrraaccttoorr:: Max Bögl

LLaauunncchhiinngg ssuubbccoonnttrraaccttoorr:: Saarens

Judges’ comment“Impressive technical achievements, particularly in the dynamics”

“Remarkable slenderness and transparency”

“This represents global and local steel design extended beyondthe usual values”

WINNER

www.bridgeweb.com


1133

Technical long span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Stadt Leer

PPrriinncciippaall ddeessiiggnneerr:: Schlaich Bergermann & Partner

PPrriinncciippaall ccoonnttrraaccttoorr:: Arge Prien-Neumann, Bremen

OOppeenneedd:: April 2006

The cable-stayed bridge spans 82m, and connects the historic old town of the city ofLeer in Germany with new office and residential areas beyond the port basin. It is

cranked in plan, a decision governed by the approaches. The two bridge parts follow thedirections of the roads leading to it, resulting in an alignment with a change in direction atthe movable central part of the span. This not only allows for interesting views whencrossing the bridge, it also fits the concept of the cable-stayed bridge which works as twofully-loadable individual cantilevers (trusses) when the bridge is open and which convertsto a continuous girder of additional transverse stiffness when the bridge is closed.

Inclining the masts towards the water minimises their height and moves the mast headsaway from the adjacent buildings, avoiding visual conflicts. Usually, single masts lead totransversely-inclined cables which reduce headroom for the user. Here, the introduction ofspreader beams which bend the cables eliminates this clearance problem and creates aninteresting space above the deck. From the centre of the bridge, where the movable steel-only deck is 3m wide, the deck width increases to 4m along the fixed part of the span,which is a composite section with a 20cm-thick concrete slab and total height of 600mm,and up to 5m at the massive concrete abutments that support the inclined mast.

This dramatic footbridge was built as part of the new infrastructure required when thecity of Turin played host to the Winter Olympics in 2006. The bridge, designed by Hugh

Dutton Associes, was intended to provide a symbolic focal point for the entire Olympicvillage as well as a sculptural symbol of the Games which would remain after the event.

The inspiration for the parabolic arch was found in the concrete arches of the existingMercati halls next to the site. The arch has a slight lateral inclination to optimise the planangle of the suspension cables with respect to the steel deck as its curved path swingsacross the span. The lightweight suspension design and long span leads to dynamicsensitivity, and in response, the deck edge profile was refined using a wind tunnel tooptimise the shape and ensure stability. Pedestrian comfort simulation was carried outduring the initial design phases exploiting the curved deck geometry to efficiently damphorizontal sway with viscous jacks at the ends. V and N-shaped column configurationsprovide optimal structural support while maintaining a light, floating visual effect for thedeck. The steel triangular section of the arch made it possible to achieve the paraboliccurve in cold formed conical segments and achieve a crisp and pure profile that respondswell to diurnal and nocturnal light.

“The geometricalsolution to the

site constraintscan be

appreciated.”

Judges’ comment Judges’ comment

Technical long span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Agenzia Torino

PPrriinncciippaall ddeessiiggnneerr:: Hugh Dutton Associes

PPrriinncciippaall ccoonnttrraaccttoorr:: ATI Sermeca Falcone

OOppeenneedd:: February 2006

“The V and N-shaped columns

are interesting onthis sculpturalsymbol of the

Olympic games”

NESSEBRIDGE, LEER, GERMANY PASSERELLE 2006 TURIN OLYMPIC VILLAGE, ITALY

www.bridgeweb.com


The project to build a new footbridge over the River Dravain Maribor essentially involves the reconstruction of an

old bridge, strengthening the existing supports and buildinga new superstructure.

Despite its relatively simple and clear structural system,the new bridge is distinctive because of the interactionbetween its walking surface and structure elevation.However the transparency of the truss structure and itssymmetry mean that while being distinctive, the bridge alsoblends in with the environment and river landscape. Addedto this, the configuration and the original design made itpossible to use an interesting and economic method ofconstruction for the new crossing.

The bridge was built in 1885 using three simply-supported truss girders on wooden supports in theriverbed. After a flood in 1903, intermediate masonrysupports were added to the bridge, but in World War II itwas destroyed and reconstructed. Again in 1946 it wasswept away by floods, and two years later rebuilt. A hydro-electric power plant built in 1968 made it necessary toraise the river’s water level by some 5m.

To minimise the construction costs the supports of theold footbridge have been used, which dictated three spanseach 42m long, yet at the same time it was necessary toincrease the navigation clearance under the bridge from3m to 3.6m. The solution that was chosen has a triangularsteel truss as the primary longitudinal spine structure,along which a secondary transversal structure of ribs israised. It was not possible to increase the height of thestructure at the banks, so the walking surface rises gentlytowards the centre span of the bridge, and is thus dividedlongitudinally into two parts on the end spans. As the deckrises, the spine structure disappears and the walkways join.

The footbridge is straight in plan, and its verticalalignment follows a convex curve on a radius of 1,045m,which creates a maximum gradient of 5%. In the middle ofthe footbridge the deck width is 3.2m, at the ends it is splitinto two sections of 2.4m each, divided by the spine

structure rising through the deck. The variation of thealignment was solved by dividing the structure into twosystems. The main steel structure, the spine, is a centrally-positioned triangular truss of constant structural height andwidth. It is a space truss with three longitudinal pipes in atriangular cross-section of constant form. The axialdistance between the upper and lower pipes is 1.75m,which gives a total structural height of 2.05m, while theaxial distance between the lower flanges is 1.5m. Thelongitudinal pipes have a diameter of 299mm, wallthickness of 8–20mm, and the diagonal and cross pipeshave a diameter of 114mm. The upright connectionsbetween layers are not vertical but radial, so that theelement lengths and mutual angles are constant along thewhole bridge, making construction cheaper and simpler.

The secondary structure, which consist of ribs, is raisedalong the main structure and supports the walking surface.It is bolted into place once the main structure has been

erected, and is protected by hot dip galvanising.It is composed of transverse cantilever girders and

longitudinal. The transverse cantilevers also act as aparapet, and are the same size along the whole of thebridge. The deck is made of transversely placed profiledBangkirai wooden boards, and another special aspect ofthe design is the discreet lighting, which is concealed in thehandraill, using LED diodes with just 350W power.

Construction of the new bridge was very cost-effective,using the existing structure as a support. The triangulartruss was welded into segments and progressivelylaunched over the existing structure. Dividing the bridge intwo helped reduce the transverse size of the structure somuch that this method of erection was possible. Aftererection the new structure was supported through theremainder of the old bridge. Truss elements were erectedabove the intermediate supports and the bearings grouted,after which the old footbridge was dismantled.

STUDENCI FOOTBRIDGEMARIBOR, SLOVENIA

Judges’ comment“A pleasing technical solution to a difficult set of criteria”

“Interesting new technical ideas”

Technical medium span: JOINT WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: City of Maribor

AArrcchhiitteecctt:: Reichenberg Arhitektura

PPrriinncciippaall ddeessiiggnneerr:: Ponting

PPrriinncciippaall ccoonnttrraaccttoorr:: Group Pomgrad, Konstruktor

OOppeenneedd:: December 2007

WINNER

1144 www.bridgeweb.com


Technical medium span: JOINT WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: CTP Invest

AArrcchhiitteecctt:: Studio Acht

SSttrruuccttuurraall eennggiinneeeerr:: Strasky, Husty & Partners

PPrriinncciippaall ccoonnttrraaccttoorr:: Skanska DS


Judges’ comment“The use of an original solution along with efficient constructionmethods kept the bridge within a reasonable cost.”

“Good technical innovation”

SVRATKA RIVER BRIDGE, BRNO,CZECH REPUBLIC

By the development of a new structural form and carefulconsideration of how it would be built, the team

managed to design and build this elegant footbridge at avery modest cost. The intention was to find a simplestructure that suited the location, fitted with theneighbouring bridge, and could be built easily.

The bridge was required to provide a link from the existingcity centre to a newly-developed area of office buildingsacross the Svratka River. The new bridge also had to fit withthe adjacent structure, an arch bridge with multiple spans,which had piers in the river.

The presence of this structure influenced the choice of thearch shape for the bridge, but the area suffers from poorground conditions, hence it would have been too expensiveto build a traditional arch bridge. To address this, thedesigners went one step further in developing a newstructural form for the bridge, which would make a boldstatement by crossing the river in a single, 43m-long span.

The footbridge has a stress ribbon deck, supported by aflat arch; the two parts form a self-anchored system as theyare fixed in the same abutments and as a result, only verticalforces are exerted on to the abutments. High strengthconcrete was used for the stress ribbon segments and thearch, and the erection method meant that the structure couldbe built without the need for any temporary towers in theriver. The lines of the stress ribbon deck create a smoothconnection at the abutments on each side.

Construction of the bridge began with the installation ofthe arch, which was precast in two halves and then liftedinto position and tied back with temporary cables to theabutments. These cables were used to adjust thealignment, and eliminate the effect of deformations of theshafts, before the joint was cast at mid-span. Thetemporary cables were replaced by external cables, ontowhich the segments of the stress ribbon were installed, andthen internal cables were threaded through the ducts in thesegments, and tensioned. The external cables were thenremoved, leaving the deck in the required geometry. Thejoints between the deck segments were cast, and theprestressing cables tensioned to the full design stress.

A loading test was carried out using lorries across thefull length of the bridge, and a second test with the bridge

only half loaded with lorries. It is a very stiff structure whichdoes not suffer any dynamic motion when in use.

The abutments of the bridge are located outside the oldstone walls that form the banks of the river, and aresupported by pairs of bored piles.

The rear piles are in tension while the front piles are incompression, and these forces balance the tension andcompression forces in the stress ribbon and arch.

The stress ribbon is carried and prestressed by fourinternal tendons each made up of 12 15mm-diametermonostrands in PE ducts. Both stress-ribbon and the archare made from high-strength concrete of 80MPa strength.

Construction of the bridge began in February 2007 andwas completed in September of the same year, at a totalcost of €530,000.

WINNER

1155www.bridgeweb.com


Technical medium span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Gold Coast Motor Events Company

PPrriinncciippaall ddeessiiggnneerr:: Arup

AArrcchhiitteecctt:: Cox Rayner Architects

PPrriinncciippaall ccoonnttrraaccttoorr:: Ark Construction Group/AustressFreyssinet JV


Technical medium span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Ontwikkelingsbedrijf GemeenteAmsterdam

PPrriinncciippaall ddeessiiggnneerr:: Gemeente AmsterdamIngenieursbureau

AArrcchhiitteecctt:: Kerste-Meyer

PPrriinncciippaall ccoonnttrraaccttoorr:: Hillerbrand

OOppeenneedd:: May 2005

The bridge, on Australia’s Gold Coast, crosses the Nerang River linking the island to thesurf beaches, and the bridge will also play a key role during the annual Gold Coast Indy

300 motor race. The existing bridge was closed due to safety concerns, and neededreplacing before the next Indy event, leaving only five months for the design andconstruction. The winning bidder was the only one which offered to meet the client’srequirement of a cable-stayed bridge within the very short time frame. The designincorporated extensive precasting and off-site fabrication; procurement of all of thesecomponents had to start long before design completion. Stay cables were ordered just twodays after the start of detailed design and precast driven piles two days later. In addition tothe time constraint, risk mitigation was a key issue, the solution being to erect the deck ontemporary supports to carry a full pedestrian live load, allowing the bridge to be openedearly if necessary without the towers or cables should these be delayed by weather or otherconstraint. Another challenge was the aggressive salt spray environment for which a highlydurable and well-detailed bridge was essential.(Photo: Christopher Frederick Jones)

The Oosterdoks swing bridge was designed to connect the city centre with the shores ofthe IJ, and it crosses one of the busiest navigational routes in Amsterdam. The bridge

opens around 5,000 times a year, hence a drive with two engines was chosen for reliability.It was designed to be as elegant as possible, which is why a stiffening, curved top chord

was necessary. There are no connections with partitions, endplates or nuts in sight – thestiffening chord is connected to the deck by a frame, with the path on both sides. The topchord of the framework is a steel circular pipe with a diameter of 500mm, and the braceshave an oval diameter and are oriented in such a way as to appear narrowest when seenfrom the transit. The east access ramp is partly situated above a traffic tunnel, and thefoundation piles near the tunnel had to be placed without vibrations.

Polystyrene foam was used to minimise the increase in load on the tunnel. The totallength of the bridge is approximately 125m and the deck has a height of 400mm andconsists of a rectangular bottom chord and orthotropic steel plates that have an epoxywearing course.

MACINTOSH ISLAND PEDESTRIANBRIDGE, QUEENSLAND, AUSTRAILA

OOSTERDOKS SWINGBRIDGEAMSTERDAM, THE NETHERLANDS

1166

“Five monthdesign/build

withimpressive

results”

Judges’ comment

“Carefuldetailing,

showing thetechnical

strengths ofsteel at its

optimum use”

Judges’ comment

Vela VKE is a truly South African, multi-disciplinary,consulting engineering company providing specialist

bridge design services across the globe.

As we continue to build on over sixty yearsof experience, our expertise and innovation

remain internationally recognised.

Group Head Office +27 12 481 3800Email: [email protected]: www.velavke.co.za

VV

KE

/B

RID

GE

2/04

www.bridgeweb.com


e

PLETTENBERGBAY PEDESTRIAN

BRIDGE,WESTERN CAPE,

SOUTH AFRICA

WINNER

The design of the Plettenberg Bay Pedestrian Bridgeincorporates an inclined arch with a slender steel

torsion box deck. The central span of 28.1m is supportedby the inclined arch and back spans each 9m long result ina total bridge length of 46.1m.

Although the design relies on a concept developed bySantiago Calatrava, this bridge is unusual in that it issupported by inclined circular hollow steel struts thateffectively continue the arch. The angle of the struts wasadjusted to minimise the bending moments at the fixedsupports due to the permanent loads.

The arch was constructed from single radius 273mmdiameter, 10mm-thick steel tubes and the 219mm-diameter deck elements were bent to a single radius thatbest fitted the double curvature of the deck. Double channelsections were used for the ties, in order to createtransparency and to accommodate future lightinginstallations. The deck is a trapezoidal box which is 1.6mwide and 350mm deep and is constructed of 10mm-thicksteel plate. Sizing of the box was done by reviewing thetorsional rigidity required to ensure the serviceabilityrequirements.

A key challenge was the structure’s buildability; thebridge deck is set out on both a vertical and horizontalcurve. The dimensions of the straight steel plates used tofabricate the deck were calculated mathematically andchecked graphically using 3D CAD software. The proposedfabrication process and erection sequence were carefullyconsidered during the design stage.

In terms of the bridge’s detailed design, fatigue stresseswere a significant consideration. As it is a fixed arch, thetemperature load case was important as were the effects oflongitudinal sway due to asymmetric live loads. The transferof the torsion moments induced in the deck, and thecompressive stresses from the arch into the inclinedcircular steel struts, required careful detailing of theconnections. The biaxial bending moments in the strutvaried significantly and a circular section was thereforechosen as suiting the structural requirements as well as the

overall aesthetics. The steel base plate of the strut wasprestressed against the reinforced concrete base to reducefatigue stresses. A dynamic analysis was undertakenconsidering load models of a single pedestrian, apedestrian group and a continuous pedestrian stream.

After the final welding of the structure was completed inthe fabrication yard, the arch was dismantled and the deckdivided into four separate sections which were thentransported 500km to the site. Due to the time constraintsassociated with closing National Route 2, contractorCivils2000 elected to lift the entire 49.1m-long deck intoplace in a single lift. But the manoeuvrability of such a longstructure presented severe challenges. An application toreassemble the bridge in the central island of the highwaywas submitted and approved to minimise the liftingdistances.

After being reconstructed in the central island, thebridge was lifted into place using two 220t cranes andwelded onto the circular steel supports. Dimensionalaccuracy with this approach was essential; a laser survey

of the completed bridge in the fabrication yard wasundertaken. The deck’s as-built dimensions were thenchecked against the construction tolerances achieved insetting out the supporting steel struts on site.

The construction of the bridge has provided safecrossing to the many pedestrians walking to and fromPlettenberg Bay each morning and evening. Pedestriansuse the structure because it follows their desire lines andcan be accessed at grade from existing footpaths. Theproject forms part of South Africa National Roads Agency’spedestrian safety improvements along the National Route2, and in addition, its design is integrated into atransportation hub incorporating a labour desk office andablutions. This is aimed at encouraging pedestrians to usethe bridge and ensuring that vehicles do not stop on thehighway. The bridge won the South African Steel AwardsBridge Category for the high level of workmanship visible inthe structures fabrication and its integration into the naturalbeauty of South Africa’s Garden Route has also won praisefrom local communities.

1177www.bridgeweb.com

Technical short span: WINNER

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: South African National Roads Agency

AArrcchhiitteecctt:: Ahmed Janahi

PPrriinncciippaall ddeessiiggnneerr:: Vela VKE Consulting Engineers

PPrriinncciippaall ccoonnttrraaccttoorr:: Civils2000

OOppeenneedd:: January 2007

Judges’ comment“Interesting asymmetry”

“The innovation and the designers’ use of technology make itstand out from the crowd”


1188

Technical short span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Auckland Regional TransportAuthority

PPrriinncciippaall ddeessiiggnneerr:: VSL Australia

SSttrruuccttuurraall eennggiinneeeerr:: URS New Zealand

PPrriinncciippaall ccoonnttrraaccttoorr:: Dominion Constructors

OOppeenneedd:: August 2007

Technical short span: HIGHLY COMMENDED

CCoommmmiissssiioonniinngg aauutthhoorriittyy:: Stadt Baden-Baden

PPrriinncciippaall ddeessiiggnneerr:: Schlaich Bergermann & Partner

PPrriinncciippaall ccoonnttrraaccttoorr:: Max Frueh

OOppeenneedd:: June 2006

The ultra-high performance concrete Ductal was used to build a replacementfootbridge for Auckland Regional Transport Authority at Papakura Station.The conforming design consisted of an ordinary reinforced concrete U-shaped beam

superstructure supported by large circular steel columns on pad footings. But the use ofDuctal reduced the superstructure weight and offered the freedom to produce a moreinteresting shape. Ductal licensee VSL Australia proposed an efficient Pi-shaped beamsolution with an integral deck and large circular penetrations through the webs. The deckis only 50mm thick, cantilevers 400mm out from each leg and does not contain anyreinforcement other than the steel fibres in the UHPC.

Ductal is almost self-placing, has a compressive strength of 150-200MPa and aflexural strength of 30-40 MPa. The solution offers a weight saving of 65% over thereinforced concrete solution, resulting in the size reduction of the supporting columnsand pad foundation and an overall material cost saving. The footbridge has a total lengthof 178m consisting of nine simply-supported spans between 10.2m and 25.4m long.

This two-span pedestrian bridge crosses the main connecting highway between thecity of Baden-Baden and the Rheintal highway in southwestern Germany. The

concrete deck has two spans of 18m; it has no bearings and acts as an integralstructure with a rigid connection to the abutments and to the Y-shaped column dividingtwo directions of traffic flow on the highway below. This offers a robust solution and lowmaintenance by avoiding the need for inspection in the future. To reduce bending stressin the structure, the slender walls of the supporting abutments are quite flexible and thesoil behind them is stabilised with cement to prevent any interaction between it and theabutments.

In the transverse direction, the deck consists of a central section with constant depthand two tapering edges, increasing the impression of slenderness in elevation. It wasbuilt to a very tight construction schedule and within the defined budget.

PAPAKURA STATION FOOTBRIDGEAUCKLAND, NEW ZEALAND

FOOTBRIDGE CITE BADEN-BADEN,BADEN-BADEN, GERMANY“The

innovative useof UHPC

offers reducedthickness andweight in the

structure”

Judges’ comment

“Elegant andsimple”

Judges’ comment

www.bridgeweb.com


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Papakura Footbridge, Auckland, New Zealand: Finalist Footbridge 2008 Award, Short Span Category.

Mars Hill Bridge, USA fi rst Ductal® highway bridge, Wapello County, USA.

a revolutionarybuilding material

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an innovative, economical and sustainable solution becomes a reality.www.ductal.com

Outstanding durabilityEnticing aesthetics and low weightExtraordinary slenderness and strength

www.vsl.com

230x297_Lafarge-ductal_uk.indd 1 16/06/2008 13:00:35

anónimo - footbridge awards 2008

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