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Winning projects represent supreme global engineering feats The InsƟ tuƟ on of Structural Engineers (IStructE) announced the winners in November last year
SUPREME GLOBAL ENGINEERING FEATS WINNING PROJECTS REPRESENT
The InsƟ tuƟ on of Structural Engineers (IStructE) announced the winners of The Structural Awards 2019 during a gliƩ ering black-Ɵ e event held at The Brewery, London, UK, in November last year.
The winners were chosen from a shortlist of 49 pioneering global projects in 12 categories, celebraƟ ng the ingenuity and experƟ se of the engineers behind them. A diverse range of structures was recognised across 12 categories. The entries underlined the creaƟ vity of Structural Engineers and their ability to harness digital tools to design structurally effi cient buildings. The winning projects showcase cuƫ ng-edge examples of innovaƟ ve engineering soluƟ ons. The New ToƩ enham Hotspur Stadium, UK, received the 2019 Supreme Award for Structural Engineering Excellence. The coveted accolade is presented to the year’s fi nest example of Structural Engineering design. The judging panel, made up of a disƟ nguished group of industry experts, were unanimous in their view about the cable-net roof structure, which is a vital feature of this redevelopment project. The judges were impressed by the ingenuity shown by the structural designers in dealing with very challenging constraints and requirements. They added that the aƩ enƟ on to detail throughout is exemplary and is an excellent showcase for the structural engineer’s art. Structural innovaƟ on is evident in the sliding pitch, vast open concourses and an almost impossibly light roof. They felt that the sheer elegance of structural form, lighttouch use of resource, and outstanding detailing evident in key connecƟ ons all pointed to design worthy of the 2019 Supreme Award. Chair of the judges, Professor Tim Ibell, commented, “Many congratulaƟ ons to all the winners and thanks to those who entered the awards. Each year, the quality of the projects keeps geƫ ng beƩ er. This year, we saw some excellent examples of the exploitaƟ on of digital tools, geometry, choice of materials to improve and enhance structural behaviour and, most importantly, the carbon footprint”. He conƟ nued, “Keeping in mind the current climate crisis; we must pledge to build structures which are kind to the environment. Reuse and refurbishment should be our adopted mantra. With the net zero carbon target in sight, we wholeheartedly support the Structural Engineer’s DeclaraƟ on which encourages companies and us to change the way we work”. Now in its 52nd year, these presƟ gious awards celebrate the world’s most outstanding achievements and demonstrate the diversity of structural engineering, recognising excellence, creaƟ vity and innovaƟ on, as well as sustainability, economic viability and value for money.
The Structural Awards The Structural Awards are the world’s foremost celebraƟ on of Structural Engineers as innovaƟ ve, creaƟ ve design professionals and the guardians of public safety. For over 50 years, the Structural Awards have showcased the world’s most cuƫ ng-edge engineering achievements. Past winners include iconic structures such as the Sydney Opera House, the Pompidou Centre and the Severn Bridge. All entries are reviewed by a panel of world renowned judges who are truly passionate about structural engineers’ contribuƟ on to society as design professionals.
The InsƟ tuƟ on of Structural Engineers The InsƟ uƟ on of Structural Engineers (IStructE) is the world’s largest membership organisaƟ on dedicated to Structural Engineering. IStructE leads and supports the development of Structural Engineering worldwide, in order to secure a safe and resilient built environment for all.
New ToƩ enham Hotspur Stadium, London, UK, Winner of the 2019 Supreme Award for Structural Excellence and the Award for Long Span Structures. Engineer: BuroHappold Engineering and Schlaich Bergermann Partner. Images by HuŌ on+Crow.
AWARD WINNING PROJECTS
THE AWARD FOR LONG SPAN STRUCTURES Project: New ToƩ enham Hotspur Stadium, London, UK. Engineer: BuroHappold Engineering and Schlaich Bergermann Partner.
28 New ToƩ enham Hotspur Stadium, London, UK.
Project descripƟ on The cable-net roof structure is a key feature of this stadium redevelopment project. The fi nal design is a light
THE AWARD FOR TALL OR SLENDER STRUCTURES Project: CITIC Tower, Beijing, China. Engineer: Arup. Project descripƟ on With a height of 528 m, this 108-storey tower is possibly the world’s tallest building constructed in a high seismic zone. A gently rising and curving profi le gives the building a contemporary and elegant expression, accommodates more prime-fl oor spaces at the top levels and provides structural stability at the base. Judges’ comment “The judges were impressed with the mulƟ -faceted structural design for an extremely tall and slender building in a high seismic zone. Using parametric design , hundreds of potenƟ al soluƟ ons were explored. The tower employs a mulƟ ple lateral load resisƟ ng system with a central concrete core and a perimeter mega-frame. The external mega-frame is built from concrete-fi lled steel box secƟ ons. Belt trusses at mechanical/refuge fl oors provide further stability. An intelligent construcƟ on approach was developed using an integrated plaƞ orm - a steel frame structure set on the top of the concrete core that was jacked up as work progressed. This mulƟ -level construcƟ on plaƞ orm saved Ɵ me and cost of convenƟ onal cranes and provided a work-place in the sky. With its challenging form (widening towards the top), challenging locaƟ on (high seismic condiƟ ons) and extreme height (528 m), this tall tower presented mulƟ ple chal
weight looped cable structure with an outer compression ring and two inner tension rings. The new mulƟ -purpose stadium can seat 62,062 and will also host NFL games. Judges’ comment “This is an impressive stadium containing many dramaƟ c long span soluƟ ons. The judges were impressed by the ingenuity shown by the structural designers in dealing with very challenging constraints and project requirements. The roof is a complex lightweight cable-net structure with an external compression ring and two internal tension rings. Horizontal loads and uneven loading condiƟ ons are carried by geometrical sƟff ness only, thus opƟ mising the primary structural members to a minimum size and achieving the desired lightness and transparency. In addiƟ on to the roof, the concrete stands also incorporate long spans for various reasons, including the accommodaƟ on of the enƟ re retractable pitch which slides back under the south stand when the stadium is in use for concerts and other events. The aƩ enƟ on to detail throughout is exemplary and is an excellent showcase for the structural engineer’s art”.
lenges to its structural engineers. They developed a design that combines well-known systems in an intelligent way, including an innovaƟ ve means of construcƟ on”.
THE AWARD FOR VEHICLE BRIDGES Project: Kienlesberg Bridge, Ulm, Germany. Engineer: KREBS + KIEFER.
Kienlesberg Bridge, Ulm, Germany. Image by Knight Architects.
Project descripƟ on Kienlesberg Bridge is a combined tram, cyclist, and pedestrian bridge crossing a busy railway hub.
THE AWARD FOR PEDESTRIAN BRIDGES Project: Tanxishan Glass Landscape Pedestrian Bridge, Zibo, China. Engineer: Tongji Architectural Design (Group) Co Ltd. Project descripƟ on Spanning two cliff s on the top of Tanxi Mountain, this curved girder bridge is supported by a single-side cable arch system. Due to the harsh and narrow construcƟ on space on the top of the mountain, an innovaƟ ve construcƟ on method was required. Judges’ comment “The form of the bridge has created a landmark for the area with its long spanning elegant profi le both in the sweeping horizontally curved glass desk and its verƟ cally curved inclined arched support. Connected by cables, together they generate a sculptural form in this mountainous region. It is clearly man-made yet compliments its surrounding natural environment. The structural engineering ambiƟ on, execuƟ on of engineering judgement, thoroughness of design and delivery clearly contributed to the success of this bridge. The engineer’s role as part of a team of close collaborators from many diff erent design and construcƟ on professions is evident in the fi nished bridge. The bridge is fl anked by dramaƟ c mountainous terrain that challenged the team to design for complex topography in a remote site with narrow construcƟ on space The 270 m-long crossing has a unique undulaƟ ng appearance. The structure was prefabricated in segments which were welded on site and launched over live rail traffi c. Judges’ comment “This is a highly sympatheƟ c new pedestrian, cyclist, and tram bridge. The structure refl ects the enormous benefi ts of interdisciplinary work between engineers and architects. The sinuous silhoueƩ e is derived from the natural distribuƟ on of bending moments, and opƟ mised for a longitudinal launching process. At the same Ɵ me, it is an architectural homage to the nearby 110-year-old wrought-iron Neutor Bridge. The judges admired how the graceful, economic, and effi cient appearance belies the complexity of the site and irregularity of the support condiƟ ons. Notably, the structure of the main crossing was prefabricated in short segments, assembled on an elevated scaff olding at the south abutment and truss adjacent. This three-stage launch procedure was complicated by the curved east secƟ on but well managed by the engineers”.
and challenging access. The team used 3D laser scanning technology to model the topography and integrated it into the design model. Considerable aƩ enƟ on to feasible and effi cient construcƟ on led to an innovaƟ ve two stage rotaƟ on of girder and arch construcƟ on sequence which reduced the temporary works requirements. To achieve this, key hinge joints that performed for both the permanent and staged temporary construcƟ on cases were developed and a special climbing construcƟ on device was designed for construcƟ on of the curved structure. Effi ciency in form was also considered by load balancing arch and deck allowing for a single-sided cable soluƟ on. The fi nal bridge soluƟ on is a sophisƟ cated resoluƟ on of complex Structural Engineering consideraƟ ons realised in an elegant form”.
THE AWARD FOR SMALL PROJECTS (of under GBP 3 million) Project: Millet Vinegar Museum, Zibo, China. Engineer: Light Earth Designs. Project descripƟ on The entrance hall of the museum is a newly built dome with a height of 9.1 m and a diameter of 12 m. The construcƟ on scheme combined use of a local brick kiln with the latest masonry technology. Judges’ comment “The Millet Vinegar Museum’s beauƟ ful brick dome stands 147 brick courses high and punctured by three large arched openings. While in some ways this may be seen as a tradiƟ onal structure, the engineers’ approach to the design was evidently meƟ culous and bold. The dome is in the highly seismic Shangdong Province area of China. The engineers were clearly resistant to the temptaƟ on to betray the pure brick form with steel or other ducƟ le fi xings. Instead, they relied on their confi - dence, borne of accurate and considered analysis and opƟ misaƟ on of the dome shape, to resist lateral forces. Each layer of bricks was carefully planned and sequenced to avoid formwork. Subtle rotaƟ on of the various courses of bricks achieved the decoraƟ ve texture of the arched openings. The result is a splendid example of a project made both conceptually and aestheƟ cal beauƟ ful by an engineer’s skilled and sympatheƟ c guiding hand”.
Millet Vinegar Museum, Zibo, China.
THE AWARD FOR STRUCTURES IN EXTREME CONDITIONS
Project: Tūranga, Christchurch, New Zealand. Engineer: Lewis Bradford ConsulƟ ng Engineers.
Project descripƟ on A new central library built following the devastaƟ ng 2010-2011 earthquakes in Christchurch. Tūranga was constructed to very stringent seismic performance criteria and features state-of-art seismic resisƟ ng systems.
Judges’ comment “The concept for this fi ve-storey, 10,000 m 2 library was inspired by the 2010-2011 earthquakes that aff ected Christchurch, New Zealand, where the majority of buildings remained safe, but a great number were uneconomic to repair and required demoliƟ on. able to ‘rock’ due to their connecƟ on to the foundaƟ ons and to adjacent components being made with replaceable shock-absorbing devices. They work in conjuncƟ on with a perimeter steel moment resisƟ ng frame which also has rocking base connecƟ ons. The engineers were instrumental in encouraging plant, that would have been positioned in a basement, to be placed on the roof, allowing the proposed basement to be removed from the scheme. This enables the building to be constructed off a shallow gravel layer, avoiding both the expensive basement and costly piled foundations. A great example of how structural engineers can make such a crucial diff erence to a building, this is in every sense - a building that rocks!”
Tūranga’s hidden beauty lies in its level of seismic resilience, such that aŌ er a serious seismic event, the shock absorbing systems could be readily replaced and the building would be re-usable. The massive concrete core walls, some weighing around 140 tonnes, were cast fl at on site and then ‘Ɵ lted up’. They provide stability to the building and in a seismic event are
THE AWARD FOR STRUCTURAL HERITAGE Project: Newquay Harper Bridge, Newquay, UK. Engineer: Free4m.
Newquay Harper Bridge, Newquay, UK. Image by Free4m.
Project descripƟ on RestoraƟ on works to this footbridge returned it to its original structural design, preserving one of the few ‘Harper Bridge’ designs remaining in the UK and an important piece of BriƟ sh engineering history. A method was devised by the engineers to carry out the restoraƟ on without support works, allowing the bridge to remain open throughout and creaƟ ng a considerable cost-saving for their client. Judges’ comment “The structural engineers carried out considerable research into the history of the bridge and even consulted with the original designer’s grandson who himself researched the history of Harper bridges. The scheme recognised that only the suspension bridge hangers were in need of replacement and researched the original details thus returning it as close as was feasible to its original design. In this way, the suspension cables were saved, which resulted not only in a highly sustainable solution but saved significant cost and areas of the original structure. The judges were parƟ cularly impressed by this minimalist approach which was underpinned by detailed research and sound engineering judgement”.
THE AWARD FOR STRUCTURAL TRANSFORMATION Project: Coal Drops Yard, London, UK. Engineer: Arup. Project descripƟ on Two Victorian train sheds and arches were transformed to create a retail centre and focal point for London’s King’s Cross development. The project combined Victorian engineering with contemporary intervenƟ ons that enhance the historic architecture and features a striking new roof and fl oaƟ ng fl oor. Judges’ comment “This transformaƟ on project required intricate structural design soluƟ ons to ensure faithful delivery of the fi ne architectural aestheƟ cs. RestoraƟ on and renovaƟ on of the existing brick, Ɵ mber and cast-iron structures was carried out aŌ er individual assessment of their structural viability, retaining as much of the original materials as possible. The success of the development relied upon the creaƟ on of a suspended fl oor linking the East and West Coal Drop buildings, thereby creaƟ ng a unifi ed public area protected by the peeledback slate roofs complemented by infi ll glazing to the lenses created by the new roof geometry. This was achieved through an elegant roof structure consisƟ ng of a primary Ɵ ed arch at the centre of the new deformed roof plates, which in turn supports secondary trusses following the curved geometry of the roofs and from which the new fl oor is suspended. The primary truss has a moment-resisƟ ng V-notch at its apex in order to faithfully maintain the aestheƟ c of the ‘kissing’ roofs. Torsion and defl ecƟ on of the curved trusses were carefully calculated and systemaƟ cally monitored throughout the construcƟ on process in order to maintain deformaƟ on of the suspended fl oor within predetermined acceptable limits. The design team have skillfully combined sensiƟ ve renovaƟ on of neglected heritage structures with complex extensions to form a seamless and integrated composiƟ on”. Coal Drops Yard, London, UK. Image by Argent / John Sturrock.
THE AWARD FOR CONSTRUCTION INNOVATION Project: Morpheus Hotel, Macau, China. Engineer: BuroHappold Engineering.
Morpheus Hotel, Macau, China. Image by Virgile Simon Bertrand.
Project descripƟ on The fiŌ h tower in Macau’s ‘City of Dreams’ leisure and entertainment complex stands 160 m high. The hotel accommodaƟ on is arranged around a core in each wing of the building. The exoskeleton structure of the building works with two concrete cores, providing the main verƟ cal and horizontal load-bearing elements and upholding the client’s vision for a unique building. Judges’ comment “The Morpheus Hotel was recognised by the judges as being a forerunner in the new digital era of construction. The entire project from the initial visualisation of form, through the evolutionary development, analysis and design of different viable structural options, to the optimisation and bespoke manufacturing of the structural components and the control of their sequenced erection on site, could not have been accomplished without the formidable range of digital and communicational skills that characterise the structural engineer of today. When the unknown can be made known, the impossible can become possible and the value of the structural engineer is revealed in its true light. We look forward to the next step into the unknown!”
THE AWARD FOR STRUCTURAL ARTISTRY (Building Structures) Project: Qingdao World Expo City, Qingdao, China. Engineer: China Architecture Design & Research Group. Project descripƟ on This cross-shaped exhibiƟ on gallery connects 12 independent exhibiƟ on halls. The gallery is open on all sides, forming an open light layout. The elegant prestressed cable-arch structural system uses triangular fl exible Ɵ es, PC plates on the roof, and diff erent connectors spreading all over the structure. Judges’ comment “Arranged in a cruciform plan with a 500 m long, 47 m high primary gallery intersected by a 300 m long, 32 m high cross gallery, the structure creates a magnifi cent light-fi lled circulaƟ on area between large exhibiƟ on halls. The primary gallery height is dictated by the surrounding buildings and being in a coastal area it experiences high wind loading. To maintain the lightest of structures, a novel prestressed cable arch was developed, with a fabricated box secƟ on of just 500 mm depth to span 48 m. It is esƟ mated that the use of the cables has permiƩ ed a steel weight saving of up to half compared to a tradiƟ onal arch structure. Cast steel components, from cable clamps to arch base pins have been skilfully pared down for the most compact of connecƟ ons and have enabled quick and safe construcƟ on on-site. The judges parƟ cularly admired the simple elegance at the intersecƟ on of the crossing galleries and the visual coherency of the structure”. Qingdao World Expo City, Qingdao, China.
The Award for Structural ArƟ stry (Non-building structures) Project: Vessel, New York, USA. Engineer: AKT II.
Vessel, New York, USA. Image by Timothy Schenck.
THE AWARD FOR SUSTAINABILITY Project: La Reference, Ganthier, HaiƟ . Engineer: Eckersley O’Callaghan. Project descripƟ on A charitable engineering project supported the construcƟ on of a new secondary school in HaiƟ , providing new classrooms to 150 students.
Situated in a highly seismic zone and an area prone to hurricanes, the school’s resilience was paramount.
Judges’ comment “This pro-bono-designed school project in HaiƟ pulls together numerous potenƟ al Structural Engineering aspects of sustainable design. Following the recent devastaƟ on caused by earthquakes and hurricanes, pragmaƟ c soluƟ ons have been required in order to rebuild. This school project not only exemplifi es a resistant structural soluƟ on, but it does so in close collaboraƟ on with local engineers and construcƟ on teams.
All documentaƟ on and processes were methodically designed to develop local understanding of structural behaviour and become educaƟ onal tools for replicaƟ on, ensuring a social
Project descripƟ on This interacƟ ve sculpture creates a new innovaƟ ve centrepiece for the Hudson Yards redevelopment. Designed as a laƫ ce of ramps and landings, forming a rigid, monolithic structure, Vessel is characterised by inner and outer layers of stairs comprising almost 2,500 individual steps. Judges’ comment The structural engineering challenges that were met to deliver this piece of urban inhabitable sculpture ranged through analysis, design and construcƟ on. But for each of these, the uniqueness of the structure meant the challenges themselves were also unique. The structure is the architecture and vice versa and with the form comparable to a massive spring, addressing vibraƟ on was more complex than in other structures and was met with impressive engineering analysis and design”.
legacy within and beyond this specifi c project. Design decisions incorporated local materials and skill-availability, with the challenging design loads and respecƟ ve detailing. Limited resources required creaƟ ve design approaches and innovaƟ ve soluƟ ons to develop ducƟ le connecƟ ons resistant to earthquakes with minimal addiƟ onal material from tradiƟ onal seismic construcƟ on. All this was achieved whilst coordinaƟ ng with other disciplines for natural venƟ laƟ on, daylighƟ ng and acousƟ c performance, ulƟ mately providing a nourishing educaƟ onal atmosphere”.