Aquatics Centre, London 2012 Olympic and Paralympics Games

© Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin. Bautechnik 89 (2012), Heft 10 701

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Mike King, Gordon Mungall

Aquatics Centre, London 2012 Olympic and Paralympics Games

1 Site constraints

The Aquatics Centre is constructed on one of the mostchallenging and constrained sites on the Olympic Park(Fig. 1). The building is tightly wedged between railwaylines to the east and the Waterworks River to the west.The site is so constrained that in Games mode the west-ern temporary stands actually cantilever over the river insome areas and the eastern temporary stands extend towithin 8 m of the railway. Two tunnels were constructedbeneath the Aquatics Centre site prior to works beginningon the building. The tunnels are 4.15 m and 3.82 m inter-nal diameter and carry high voltage electricity cables. Thetwo tunnels are referred to as the Power Lines UnderGround (PLUG) tunnels. The external crown of both tun-nels is approximately 26 m below the site surface. Thetunnel alignments do not relate in any way to the buildingover. They have formed a major constraint on the site andhave had a significant effect on the building substructurescheme.

At the northern end of the site the building has been builtintegrally with one of the main entrances to the OlympicPark which bridges the Waterworks River and rail lines.

DOI: 10.1002 / bate.201201565

The Aquatics Centre is a centrepiece of the London 2012Olympic and Paralympic Games. Already now before the open-ing of the Games it is regarded as an iconic legacy building.The building comprises a 50 m competition pool and 25 m divepool under the wave-form roof of the main pool hall. A 50 mtraining pool is situated beneath the Olympic Park entranceplaza structure which is built integrally with the rest of thebuilding.The engineering strategy has been developed around two basic configurations; the Games mode and Legacy Mode.In the Games mode the facility has a maximum gross spectatorcapacity of 17 500 for use for the London 2012 Games as well ashousing facilities for the running of these events. In that modetemporary stands to the east and west of the competition anddiving pools will seat approx. 15 000 spectators. In the legacymode the building temporary seating will be dismantled and thebuilding will be a permanent pool facility for the local communi-ty as well as national and international swimming events beyond the Games.Each pool tank is provided with a combination of floating floorsand movable sub-division boom bulkheads to allow multiplelegacy and community use.

Keywords Olympic swimming hall; temporary stands for 15 000 spectators;11 000 m2 waveform roof; 120 m clear roof span; concrete dive boards

Schwimm-Arena der Olympischen und der Paralympischen Spiele London 2012Die Schwimm-Arena ist eines der Hauptgebäude der Olympi-schen wie auch der Paralympischen Spiele in London 2012.Schon vor Beginn der Spiele wurde es zu einer baulichenIkone. Unter einem wellenförmigen Dach befinden sich ein 50-m-Schwimmbecken sowie ein 25-m-Becken mit Sprung -türmen. Das 50-m-Aufwärmbecken liegt unter einem der Ein-gänge zum Olympia Park, der so genannten Plaza.Die ingenieurtechnischen Planungen erfolgten gemäß denunter schied lichen Anforderungen der „Games Mode“ und der„Legacy Mode“ nach den Spielen. Während der Spiele be -stehen Tribünenplätze für 17 500 Zuschauer sowie alle damitverbundenen sonstigen räumlichen Anforderungen. Die west-lich und östlich der Becken gelegenen temporären Tribünennehmen 15 000 Zuschauer auf. Für die „Legacy Mode“ werdendiese wieder abgebaut und die Schwimmhalle wird dann vonder breiten Öffentlichkeit und für nationale wie internationaleSchwimmwettbewerben genutzt. Alle Schwimmbecken ver -fügen über höhenverstellbare Böden und Unterteilungen.

Keywords Olympische Schwimmarena; temporäre Tribünen für 15 000 Zuschauer;11 000 m2 wellenförmige Dachkonstruktion; 120 m freitragende Dachspannweite;Stahlbeton Sprungtürme

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Fig. 1 External bird’s eye view (Games Mode)Luftbildaufnahme (Games Mode)

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M. King, G. Mungall: Aquatics Centre, London 2012 Olympic and Paralympics Games

The training pool has been constructed beneath the‘Plaza’ structure of these entrance bridges.

2 Roof structure

One of the key challenges of the project was developingthe structure for the spectacular 11000 m2 wave-formroof which is supported on only two concrete cores to thenorth and along a 22 m length of wall to the south.

The architect’s roof geometry was “inspired by the fluidgeometry of water in motion”, with the lower surface bel-lying between the diving and competition pools to helpdescribe two different zones within the one building vol-ume. The two sides of the roof sweep upwards, emphasiz-ing the wave form and also allowing the pool hall in lega-cy mode to be flooded with natural light. The key driverto the arching form of the two sides, however, was theneed to provide column-free sightlines to all 17 500 spec-tators to the far-side lane of the competition pool inGames mode.

2.1 Early roof structure development

The roof structure developed at concept stage in early2007 utilised two primary arched 3-dimensional trusses,one on each side of the roof, to span the approximate

120 m north to south dimension over the main pool hall.These arches were inclined outwards away from the cen-tral axis of the building and were supported on inclinedconcrete buttresses at both the northern and southernends of the building. Post-tensioned ties were proposedwithin the ground floor concrete structures either side ofthe pool in order to restrain the thrusting and spreadingforces at the buttress bases resulting in mainly verticalforces supported on the foundations below. The 2-dimen-sional trusses spanning between the primary arches werehighly efficient as their downward curvature combinedwith the outward incline of the primary trusses acted to-gether to ‘lift’ the trusses to resist gravity loads (Figs. 2.and 3).

2.2 Contractor consultation and final roof structure

In the summer of 2007 as part of the ‘Competitive Dia-logue’ process of discussions and consultations with pos-sible main contractors a clear message came back thatthere was a perception of risk associated with the primary3-dimensional arched trusses and particularly with thepost-tensioned substructure tie that would have requiredstage-stressing. The message to the structural team wasclear – simplify the roof structure and reduce the percep-tion of risk in constructing the roof structure. Perceptionof risk to a contractor and particularly a steel contractorwas a critical factor at the time given that this was pre-Global Financial Crisis when contractors had full order-books and complex sports projects were considered com-mercially high-risk ventures.

The solution was to develop a structural scheme thatcould demonstrate that, although complex in overall formwas made up of a kit of simple components and could bebuilt with conventional construction methods.

The final roof structure comprises a singly symmetric 3-Dimensional system of relatively simple 2-Dimensionaltrusses (Fig. 4). These span the 120 m between southernsupport wall and northern stair and service cores. Theoverall plan form of the roof is a rounded diamond shapebeing much wider mid-span, approximately 90 m, than itsnorthern supports at 54 m apart and southern wall at

Fig. 2 Early primary and secondary roof structure conceptFrühes Konzept des Dachtragwerks mit Haupt- und Nebentrag -werken

Fig. 3 Early concept arched trussed schemeFrühes Konzept mit gewölbtem Dachträger

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M. King, G. Mungall: Schwimm-Arena der Olympischen und der Paralympischen Spiele London 2012

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22 m. The structural action of the roof is a combination ofsimple trusses in the central area spanning north/southbetween primary trusses and a more complex arching/compression-hoop action for ‘Wing Areas’ that flank thecentral zone (Fig. 5). These ‘wings’ extend 27 m each sidebeyond the outer-most directly supported central areatrusses and utilise an ingenious arching action of the outertrusses where the rise of the roof relative to the supports isgreatest. The outer trusses in the wing areas are ‘kinked’ inplan with a resulting line of tension across the roof at thewidest point resisted by a cross-tie element. The thrusts atthe ends of the arching wing areas are re sisted by roof-plane transfer trusses carrying these forces through a bal-ancing tension across the central area trusses.

In order to ensure the roof behaved as described aboveand minimise the effects on the substructure, the north-ern end of the roof is supported on fixed spherical bear-ings to act as true ‘pins’. The southern end is supported onthree sliding spherical bearings along the top of the south-ern wall with the outer two bearing sliding in both prin -ciple axes and the central bearing only allowed to slidealong the central axis of the building. This was in order toavoid the support wall attracting thrust to simplify thesub-structure construction and to permit the roof to ex-pand under temperature effects.

2.3 Erection methodology

The design construction sequence was developed to per-mit the roof erection prior to the pool tank and generalbuilding construction after the completion of the threeroof support structures.

The relative simplicity of the south roof support com-pared to the cores resulted in the roof erection commenc-ing from the south (guided) support then progressing to-wards the north (pinned) cores. The erection commencedon completion of the piling which permitted the creationof a level site to allow ready crane access. The roof wascompleted in sections across its width supported on threetemporary trestles along the 120 m roof span. On comple-tion of the roof steelwork assembly, the trestles could beremoved to allow the steelwork to take its own weightand span the 120 m distance between the support points.Rather than developing a jacking down sequence at thetop of each trestle support, the roof was lifted by strandjacking at the southern end until clear of all trestles. Thetrestle heads were then reduced and the roof loweredonto its permanent guided support bearings at the south-ern end.

3 Structural steelwork components

The primary structure was fabricated entirely of straightH-sections fabricated from plate with flanges orientedvertically and equal-width sections for chords and bracesto facilitate ease of fabrication at joints. Plate girders wereused on some trusses where they narrowed to acute an-gles at their ends. The gross curvature of the primarystructure was formed by faceting the truss chords at nodepositions. The more detailed curvature supporting theroof cladding was achieved through bending of simpleUB sections in a vertical plane only (Fig. 6). Within theroof the more refined curvature was achieved by a profile-cut ‘kerto’ laminated timber subframe for supporting thetimber ceiling.

Fig. 4 Final roof structure schemeFinales Dachtragwerk



Fig. 5 Main tones of final roof structureHauptbereiche des finalen Dachtragwerks

Fig. 6 Universal beam purlins curved in vertical plane onlyAllgemein gekrümmte Pfetten, nur in vertikaler Ausrichtung



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With such a complex geometric shape 3D coordinationwith the architecture and services was crucial. All struc-tural modelling and analysis was carried out in 3D andwas transferred directly with the architect for importationinto their model to allow geometry checking and clashdetection.

The soffit geometry of the roof was set to ensure adequatesightlines from the games mode stands. The roof steel-work geometry was then pre-set from this profile to en-sure that roof deflection would not compromise the sight-lines (Fig. 7).

4 Foundations and interaction with the PLUG tunnel

The ground conditions at the chosen site were poor withalluvium overlying Lambeth clay and thanet sands atdepth. The relatively high loads imposed by the buildingand the critical nature of maintaining horizontal pooltanks meant that the foundations required to adopt pilingto transfer load to the competent underlying strata. Thefoundation solution was further complicated by the pres-ence of the PLUG tunnels.

As a result, the Aquatics Centre and Games mode standsare supported on a total of 1800 contiguous flight auger(CFA) piles and 26 No steel driven piles which were usedonly within the river. The method and diameter of the piling was chosen following detailed negotiation with thePLUG tunnel owners. The permitted development rightsagreement allowed construction over the tunnels provid-ed the load over the tunnels did not exceed those used inthe tunnel design, and did not affect their integrity. Thisagreement stipulated that all piles within a 45° influencezone required to be sleeved to tunnel invent.

Having completed some initial sensitivity analysis of theground/structure interaction around the tunnels, ArupGeotechnics carried out detailed finite element analysisof the tunnels, ground and piling loads, and were able todemonstrate that conventional CFA piling could be in-stalled close to and, in some instances directly over thetunnels, without exceeding the tunnel design loads(Fig. 8).

This work avoided the potential need to bore and sleeveeach pile resulting in mitigation of programme and costfor the Aquatics Centre as well as avoiding the need toconstruct the piles under bentonite as would have beenrequired by the prevailing ground conditions. The adop-tion of CFA piles also assisted in mitigating cross contam-ination of the perched contaminated water table with theuncontaminated lower water table. In areas of high loadconcentration, where the plaza bridge deck and the roofsupports occurred, it was not possible to take these loadsdirectly over the tunnels and this required the develop-ment of below ground transfer structures to span thePLUG tunnels. To limit the loads on the piles in closeproximity of the PLUG tunnels, the transfer structure wasde-coupled from the pile cap using a concrete hinge locat-ed centrally on the pile cap (Figs. 9 and 10).

Having solved the principles of the building’s founda -tions, we then needed to develop these to suit the com-plex geometry of the Aquatic Centre which was posi-tioned over the PLUG tunnels whose alignment had beenset prior to the Aquatic layout.

The large span transfer structures were finally designed tofollow the alignment of the tunnels and were used to re-solve the non-orthogonal position and arrangement of theabove ground plaza bridge support positions and theNorth Eastern building core main roof support.

The long span transfer structure below the eastern roofsupport core and also the plaza bridge pier were the twolargest single concrete pours carried out on the AquaticsCentre and required 1311 m3 and 1225 m3 of concrete tobe placed respectively (Fig. 11).

Fig. 7 3D structural model3D-Tragwerksmodell

Fig. 8 Geotechnical 3D finite element model to study interaction of piledfoundation and plug tunnelGeotechnisches 3D-Finite-Elemente-Modell zur Ermittlung des Zusammenspiels von Bohrpfählen und dem PLUG-Tunnel



Having developed a solution for the piling we carried outfurther analysis to consider the effects on the tunnels ofoverburden removal during the construction of the build-

ing and its pool tanks, basement plantrooms and associat-ed below ground transfer structures to ensure any tunnelovalisation was within original design criteria.

Fig. 9 Section through Plaza Bridge and supporting transfer structuresSchnitt der Plaza-Brücke und der tragenden Transferkonstruktion

50mm compressible fill

Singel line of reinforcementalong centreline of hinge

Fig. 10 Hinge detail for support of transfer structureAuflage-Detail der tragenden Transferkonstruktion



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5 Temporary works for excavations

The final ground floor level at the building is at 6.0 mAOD and the tidal ground water level is generally at3.0 m AOD. This resulted in the need to construct allbasement, pool tanks and foundation transfer structuresbelow water level. This was carried out by installing atemporary sheet pile wall, toed into the Lambeth clay andconnected to the new river wall construction, which thenallowed the construction footprint to be de- watered.

The Aquatics Centre temporary cut off wall effectivelyformed three sides of a box linking to the final sideformed by the river wall (Fig. 12).

On the east side, deep excavation for the North Easternroof support was required in close proximity to the newpark access road and main electrical site distribution in-frastructure cables. A temporary anchored secant pilewall was required as there was insufficient room to adoptan alternative which limited ground movement for the

electrical service, maintained access to the site, and usedpiling rigs to be mobilised for the permanent works.

6 Pool tank and basement construction

The basement and pool tank structures of the AquaticsCentre have two principle effects to resist. The first, interms of the pool tanks, is to prevent water leakage andthe second (which applies to all below ground structures)is to prevent water ingress from the high ground waterlevel plus potential river flood levels and rise in level dueto climate change and 1 in 100 storm conditions. Consid-ering the external ground water level in detail resulted inthe need for all basements, including pool tanks thatcould be empty due to maintenance, to be supported onboth vertical bearing and tension piles.

The development of the tension pile design in the 5 mdeep dive pool resulted in the need to install these with apiling platform level at the base of the tank. This was re-quired to limit the negative skin friction on the pile due tooverburden removal if the piles had been installed fromthe general ground level, 4 m higher. Early bulk excava-tion was sequenced to allow these to be installed at thelower level and then temporarily backfilled to produce ageneral level site to suit the roof erection cranage andsupport towers (Fig. 13).

The below ground pool tanks and other structures (bal-ance tanks, air ducts, plantrooms, lift/access cores) wereall designed and constructed using water retaining con-crete. Reinforced concrete was chosen as it was an eco-nomic material to deal with the complex geometry re-quired by the Aquatics Centre and durable to ensurelongevity with minimal legacy maintenance.

The basements and pool tanks were designed as a singleconjoined structure without movement joints. Controlledcasting sequences and concrete mixes, requiring carefulspecification along with appropriate concrete and rein-forcement design, were required to achieve the 150 mlong by 45 m wide basement arrangement.

NE core transferstructure

PLUGtunnels

Plaza pier transferstructure

Fig. 11 Long span transfer supporting main building cores and Plaza pierWeitspannende Transferkonstuktion der Hauptkerne und des PlazaPiers

River wall

Sheet piling

Anchored secantpile wall

Fig. 12 Temporary sheet piling and secant piles shown in red, river wallshown in greenTemporäre Spundwand und überlappende Bohrpfahlwände in Rot,abgrenzende Wand zum Fluss in Grün

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Fig. 13 Competition and dive pool from 3D Revit modelWettkampfbecken für Schwimmen und Turmspringen als 3D-Revit-Modell


All pool tanks had to fully integrate the water supplypipework, lights, foot rests, floating floors and deck leveltransfer channels required to provide a world leadingOlympic standard Aquatics facility.

7 Concrete superstructure

Of all the engineering components of the Aquatics Cen-tre, the reinforced concrete superstructure is the only onethat remains publically visible on the completed facility.The quality, visual shape and appearance were the start-ing point for the development of our structural design toensure that all could be met whilst also achieving the required structural performance in a safe and buildablesolution.

The concrete superstructure has a single movement jointwhich separates the plaza bridge structure from the re-mainder of the building. A principle reason for this was tosegregate the differing design life’s and design parameters.The plaza is designed as an adopted highway structurewith a 120 year design life whilst the remainder is tobuilding design criteria.

First of all, let us consider the plaza bridge structure.This is designed as a three span continuous portalised

frame and is approximately 80 m long and 50 m widein plan with a central span of 30 m crossing the 50 mtraining/warm up pool. The inner span support wallsand slab soffit are visually exposed and provide the ambiance to the pool hall. The visual soffit is formedfrom an insitu troughed/waffle slab to provide thevisual appearance developed for the design and all service routings were coordinated and cast within thewall and slab elements to avoid any exposed serviceruns for all the lights, alarms, power sockets, depth displays and the like. The outer support walls of theplaza bridge also provide the bearing galleries for thesite infrastructure bridges as they cross the adjacentroad/rail and river corridors and rest on the plaza struc-ture (Fig. 14).

The remaining building is separated from this highwaystructure as are the 50 m training pool tank and adjoiningelements which are constructed within the bridge sup-ports, but not attached, to allow the building to be‘peeled’ away from the bridge without affecting thebridge’s performance in any way.

From the plaza/bridge, the remaining 150 m approximatelength of superstructure is jointless in the final state buthad phased construction joints to limit shrinkage effects.This superstructure is stabilised for lateral loads by theroof support cores and a number of concrete shear wallspositioned and integral with the visible rhomboidal ex-posed walls.

The superstructure completely wraps the pool hall arenaand uses continuous slabs spanning onto band beamswhich continue to then provide support for the spectatorprecast seating terrace which was adopted for speed andefficiency. The band beams also permitted flexibility inthe support column locations which were needed by thegeometry and layout of changing rooms, dry dive trainingetc. contained within the building at ground level(Fig. 15).

At the south end, the outer structure falls away to be atground level whilst the inner ring rises to encompass thesouth roof support and scoreboard wall.

At the north end, the dramatic, complex geometry and ex-posed soffit form the welcome zone bowl which joins theupper pool hall to the plaza bridge deck. The welcomezone deck slab spans 30 m over the training pool whilstcantilevering from the end of the training pool to thesteeply raked bowl face. This surface is further complicat-ed by being punctured by the spectator access stairs. Inaddition to providing support to, and shape of the afore-mentioned, the slab is also required to resist the perma-nent arch thrust from the roof truss arch which spans be-tween the cores.

As the cores were constructed early to allow roof con-struction, a temporary tie was required to resist the archthrust for the roof (Fig. 16).


Fig. 15 Level 01 podium and welcome zone structure from 3D Revit model(pc seating units omitted for clarity)Ebene 01-Konstruktion von Podium und Welcome-Zone als 3D-Revit-Modell (ohne Sitzreihen, die aus Gründen der Klarheit weggelassenwurden)

Fig. 14 Plaza structure from 3D Revit modelPlaza-Konstruktion als 3D-Revit-Modell


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Initially, when we considered the tie being resolved with-in the slab, we considered a tension tie directly betweeneach core. However, as the cores were released for earlyconstruction, we revised our approach to take the tiesaround the cores and therefore could avoid complexityduring the core construction as the anchor ties would notrequire to be cast into the core walls (Fig. 17).

The western external face of the welcome zone is com-pleted by the exposed 30 m span reinforced concrete boxbeam providing a column free entrance to the AquaticsCentre at ground level and extends to provide cover tothe base of the external stair which is ‘cut’ into the struc-tural building façade (Fig. 18).

The visible external building edge beam and pool hallseating parapet were all designed to allow the conjoinedslab to the rear to be installed and de-propped. Thismeant that the beams were designed in principle fortheir self weight dead and live load only as a method ofspeeding construction on the non-visual elements and tolimit cracking and allow time to construct the visualconcrete.

All the complex geometry required that our designs paidparticular regard to reinforcement detailing and how thiscould be done. Design assumptions often had to be modi-fied to account for areas where the geometry requiredmultiple layers of reinforcement to combine.

The superstructure band beams also support a spinebeam which provides the support for the legacy 14 mhigh cantilever façade which is installed after removal ofthe Olympic seating. The induced loading from thefaçade resulted in the ability to support the front of theOlympic seating stands without further enhancement ofthe legacy design. All connections for these façade mul-lions are in place awaiting the legacy conversion withoutdisruption to the completed and commissioned buildingbelow.

8 Dive boards

The drama of the sloping 14 m high concrete wall behindthe dive pool provides the perfect back drop to the sculp-tural reinforced concrete dive boards (Fig. 19).

Each board rises out of the pool surround slab from apiled foundation cap which is some 4 m below pool sur-round level.


Fig. 16 Photograph of temporary tie during constructionTemporäres Zugband während des Aufbaus

Fig. 17 Principal of permanent tie designFunktionsprinzip der permanenten Zugbänder

Fig. 18 Extract from 3D Revit modell of 30 m span entrance beamAusschnitt des 3D-Revit-Modells des 30 m spannenden Eingangs -trägers

Fig. 19 Architect’s visualisation of dive towers Sprungturm-Visualisierung der Architekten



The challenges set by the geometry were unique and toensure adequate performance of all four critical require-ments; structural stability, deflection, vibration and aes-thetic appearance; we needed to consider accurate analy-sis of the constantly varying geometry along with a rein-forcement arrangement that permitted reinforcementplacement prior to enclosure of the special GRP form-work moulds.

From the architectural three dimensional design geome-try we developed extraction software which cut sectionsalong the length of the boards (Fig. 20). These sectionswere then post-processed to provide a centroid line analy-sis model and allowed us to establish the section proper-ties. The extracted sections also allowed an accurate load-ing assessment. This design work proved that the boardswere technically achievable but we then needed to carryout further work to follow the reinforcement bar posi-tions through the evolving and changing shape of thetowers. This resulted in the possibility that some rein-forcement bars which were positioned in the rear of theboard at base level moving to the soffit of the board whenit became horizontal at its tip.

To allow us to ensure that the reinforcement could bebent and placed we developed geometric definition soft-ware that extracted the three dimensional position of allbars at each section and then generated the best fit singleplane radius bar (Fig. 21).

The bar geometry model was then used at each link sec-tion to allow bars to be positioned and scheduled to suitthe required bar location. To follow the external boardprofile at each link section, and to limit surface cracking,the geometric definition software was used again to pro-vide the deformed link bars to the correct profile at eachsection (Fig. 22).

In total, the diving board family required more than 300unique link sections all with varying geometry with alllinks manufactured using standard radii bars.

To allow the reinforcement to be placed and the concreteto be cast, we provided main bar coordinate data fromour bar geometry model which was positioned and heldin location on site by templates to allow the bars to bethreaded through. To allow concrete placement, a central‘void’ was left within the cage to allow the installation ofthe concrete pump line. To ensure the concrete could beplaced and compacted fully, self compacting concretewas used for all the dive boards.

All superstructures and substructures used cement re-placement to assist with technical and aesthetic perform-ance along with sustainability targets set for the project.The superstructure concrete mixes adopted GGBS ce-ment replacement whilst the substructure used PFA. Infact, the concrete mix designs used for the Aquatics Cen-tre exceeded the cement and course aggregate replace-ment contents set by the Olympic Delivery Authority

Fig. 22 Reinforcement cage for the 5 m boardBewehrung des 5-m-Sprungturms

Fig. 21 Each reinforcement bar modelled in Rhino to aid the detailingprocessRhino-Modell der Bewehrung

Fig. 20 Architect’s 3D Rhino model “cut” into sections using scripts read for export to analysis and design softwareAbfolge von Schnitten angelegt in einem 3D-Rhino-Modell des Architekten



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(ODA) as well as providing the light colour required forthe Aquatics Centre.

9 Temporary stands

The brief for the temporary stands was to create econom-ical demountable structures that could increase the grossseating capacity of the venue from 2500 spectators inlegacy Mode to 17500 gross in Olympic and Paralympicmode. The initial response to this brief was a pair ofstands each side of the legacy building with a fluid geom-etry sympathetic to and merging with the legacy buildingwhich swept very high in the centre of the stands andcurved down at the sides of the stands. This solution re-quired a higher arching legacy roof and projected wellover the Waterworks River and also east towards the raillines. There was little repetition or modularisation of thisscheme and given the temporary nature of the structuresfor the Olympic and Paralympic events only was judgednot financially viable. A revised scheme was developedwhich was more orthogonal in plan form, repetitive andmore compact with an even distribution of spectatornumbers across the width of the stands. This enabled thestructures to be drawn closer towards the centre of thevenue with significantly less overhang at the WaterworksRiver as well as a substantial reduction in the height ofthe legacy roof and corresponding building volume.

The final structure comprises braced structural steelframes made up of standard Universal Beam and Univer-sal column sections, with all-bolted connections to enablerapid erection and later disassembly (Fig. 23). At groundlevel a complex system of braced frames had to be devel-oped to both cantilever over the Waterworks River at theWest stand and to bridge the Olympic Ring Road to theEast stand which cut diagonally beneath the structure. Inthe east-west direction each bay has its own braced framefor reasons of robustness and also due the absence of stiffconcrete diaphragms at the two suspended floor levels tocarry lateral loads to discrete lines of bracing. A singlesuspended level was created approximately 10 m off theground for concessions, toilets and circulation areas forspectators. In keeping with the temporary light-weight na-ture of these stands the floor at this level was not formedas a concrete deck but was made up of plywood deckingfixed to trapezoidal profiled steel metal decking spanningbetween non-composite UB secondary beams. At the sec-ond suspended level a platform of steel secondary beamswas formed to act as the springing point for the seatingsupport framework. The raking steel framing beams thensupport a folded steel-polymer composite sandwich ter-race system.

This terrace system was chosen due to its lightness com-pared to equivalent pre-cast concrete terrace units, easeof erection, disassembly and potential re-use.

The in-plane stiffness of the system bolted to the UB-sec-tion raker beams provided diaphragm action in resisting

lateral torsional bucking of the raker top flanges underbending and axial compression.

The Aquatics Centre for games mode was delivered a fullyear before the commencement of the London 2012games (Fig. 24).

On completion of the games, conversion works will com-mence to remove the games seating and to install the per-manent facade to create the iconic Legacy facility thatwas a priority consideration for the Aquatics Centre Design. Once complete, the Legacy Aquatics Centre willbe open to the general public and provide London with aworld leading training and event facility.

AuthorsMike King BEng (Hons) CEng [email protected] Mungall BSc (Hons) CEng [email protected]

Arup13 Fitzroy StreetLondon W1T 4BQEngland

Fig. 23 Extract from 3D Revit model of stand steelworkAusschitt des 3D-Revit-Modells des Stahltragwerks der temporärenTribüne

Fig. 24 Interior of finished swimming arena (Games Mode)Fertiggestellte Schwimmhalle (Games Mode)

Documents

Aquatics Centre, London 2012 Olympic and Paralympics Games