Expressive rationalism

Dating from the 1990s, expressive rationalism is neither a consistent architectural style nor a conscious approach. It is more a product of capitalism and mass-consumerism, and developed simultaneously in various parts of the world as the needs of cities changed in the late 20th and early 21st centuries. Although it follows on from modernism in that it furnishes cities, the two differ: expressive rationalism is complex, the buildings are usually used by large numbers (and are thus large in dimensions), and the designs are often achieved through computer modelling and advanced engineering. Herzog & de Meuron’s ‘Bird’s Nest’ National Stadium for the 2008 Olympic games in Beijing is an example. With a complex, asymmetrical mesh of steel making up the walls, roof and stairs, it has an inner skin of plastic and a transparent membrane roof. It is also full of Chinese symbolism. On its artificial island in Dubai, Burj al Arab (opposite, 1994–9) is a hotel designed by British architect Tom Wright (b.1957) to resemble a giant yacht’s sail and to symbolize luxury, wealth and power.

Zaha Hadid

Visionary Iraqi-British architect Zaha Hadid (b.1950) is celebrated for her use of vast, arching forms and creative use of materials in buildings, product design and furniture. Using unexpected spatial concepts, her buildings incorporate unusual, asymmetrical angles and perspectives, combining tiers, diagonals and fragmented geometry. As the first female recipient of many leading awards, she has blazed a trail for women working in architecture.

Amongst her most notable designs are the Vitra Fire Station (1990–3) in Weil am Rhein, Germany, with concrete planes at dynamic angles that create a sense of tension and urgency; the dramatically curved and angled Bergisel Ski Jump (2002) in Innsbruck; and the Rosenthal Centre for Contemporary Arts in Cincinnati (2003), which has a massive glass curtain wall. The Bridge Pavilion in Zaragoza, Spain (opposite) is a 280-metre (919-ft) covered bridge that formed the centrepiece of the city’s hosting of the international Expo 2008.

Herzog & de Meuron

The famed Basel architectural firm Herzog & de Meuron was founded in 1978 by Jacques Herzog (b.1950) and Pierre de Meuron (b.1950). They are known for innovative designs using new materials and techniques, as well as creative interpretations; after transforming a disused power station into London’s Tate Modern art museum in 2000, they added a new adjacent building in 2016, juxtaposing refined with raw and old with new, and utilizing dramatic angles and strip windows. The Tate extension bears comparison to their 2005 addition to the Walker Art Center in Minneapolis – a folded volume clad in aluminium. In 2004, they built the Forum Building in Barcelona, Spain, with bulging masses and cantilevered corners. Their Allianz Arena football stadium in Munich (opposite, 2005) features a quilted white plastic exterior that metamorphoses under different lighting effects. The partners’ imaginative responses to unique design problems reflect their sympathies with fine art, and in the past they have collaborated with artists such as Gerhard Richter (b.1932) and Rémy Zaugg (1943–2005).

Creative reuse

In its new embodiment, London’s Tate Modern art museum (opposite) is a successful example of creative reuse in architecture – also called adaptive reuse or architectural conservation. Formerly Bankside Power Station and built originally in 1891, the building became redundant a century later and was destined for demolition until British writer and architectural historian Gavin Stamp (b.1948) made a plea for it to be saved. Across the world, increasingly, structures that no longer serve their original purpose are being reused creatively through the application of new methods and materials. Although it is often more cost-effective to demolish a building and replace it, heritage is taken into account. Creative reuse can involve approaches ranging from reconstruction, restoration and conservation to radical new structural additions. The Pratt Street Power Plant in Baltimore, USA, was closed in 1973 but reworked for the 21st century into shops, restaurants and offices. In Duisburg, Germany, the Thyssen Steelworks was reinvented by Latz + Partner in 1999 as a public leisure space.

Biomimetics

Biomimetics – from the Greek meaning ‘imitation of life’ – describes the study of biological structures, processes and behaviours, and its application in various fields, such as product design or structural engineering. Observing how natural organisms adapt to their environments can help create efficient and/or sustainable designs (on the premise that if nature has honed a design over millions of years, it must be good). Natural structures have long inspired architects; for instance, the fan vaulting in church naves (from medieval times to Gaudí’s Sagrada Familia, opposite) mimics the branching of tree canopies. Other examples that borrow structurally from nature include the Eden Project (2001) in Cornwall, modelled after soap bubbles and pollen grains, and Foster’s Gherkin Tower (2003) in London, with a hexagonal skin inspired by a marine sponge. The Eastgate Centre in Harare (1996), by local architect Mick Pearce (b.1938), was designed to mimic the natural thermal control of a termite mound, as an alternative to using air-conditioning systems.

Sustainable design

In light of environmental concerns, there are increasing calls for architecture to be sustainable or green. Over the lifespan of a large building, the processes of construction, maintenance and demolition use a lot of energy and resources, alongside the energy used for heating, cooling and lighting in normal operation. But where buildings are concerned, younger doesn’t always mean greener: a 2012 report on New York City’s buildings found that the Empire State Building (1931) was more efficient than the supposedly ‘green’ 7 World Trade Center (2008). Much modern architecture is energy-inefficient on account of its expansive glazing and thin walls, and a frequent prioritization of style over resilient or sustainable design. For architecture to retain its credibility, it must conserve the Earth’s finite resources, reduce energy consumption, manage waste more effectively and create buildings that work with the environment. Sydney’s One Central Park (opposite, 2010–13) for example, incorporates natural lighting technology, ‘hanging gardens’, and other sustainable technology such as reainwater retention and recycling systems.

Burj Khalifa

Serving as offices, residential apartments and a hotel, the Burj Khalifa, named after the ruler of Abu Dhabi and president of the UAE, is the tallest building in the world at 829.8 metres (2,722 ft) high. Despite its unique appearance, designed to attract international notice, the structure is built on conventional construction methods, albeit modified to cope with the building’s unique demands.

The Y-shaped plan is formed by three wings connected to a central core, which makes it ultra-stable. The wings contain the residential units and hotel guest rooms, and the central core supports the colossal height of the building as well as housing all the elevators and mechanical systems. Rising above this reinforced concrete section of the building is the structural steel spire, which is decorated with traditional Islamic forms. The spire also highlights the tower’s resemblance to a spiral minaret, helping to put an otherwise universal, international building in its local historical and cultural context.

Santiago Calatrava

Early in his career, the Spanish architect, structural engineer and sculptor Santiago Calatrava (b.1951) raised the status of civil engineering through his designs for bridges and railway stations in his home country. His Montjuic Communications Tower in Barcelona (1991) on the 1992 Olympics site and the Allen Lambert Galleria in Toronto (1992) attracted significant commissions, including the spectacular City of Arts and Sciences in Valencia (1996–2005). Exploiting new technologies, Calatrava creates forms based on nature. His Stadelhofen Railway Station (1990) in Zurich features bridges and roofs above an organic, vaulted, underground arcade. His Quadracci Pavilion (2001) for the Milwaukee Art Museum, an organic, sculptural form resembling a bird about to take flight, functions as a kinetic sun-shield. One of his best-known pieces is the Turning Torso (2005) in Malmö, Sweden. Reaching 190 metres (623 ft) with 54 floors, the Torso is a twisted stack of nine pentagonal segments, each five storeys high and skewed rotationally around the central core, which is braced by an exterior steel framework.

El Palau de les Arts Reina Sofía, Valencia, 2005

New vernacular

In the 19th century, vernacular architecture came to describe functional buildings made with local materials and labour. A century or so on, new vernacular has come to refer to architecture that reinterprets traditional forms, materials and construction techniques to suit local tastes and cultures – in part to express individuality in design, but also to avoid what has been derogatorily nicknamed ‘global blanding’.

The London Olympic Velodrome (opposite, 2012) by Hopkins Architects, is clad in red cedar and designed to reflect the flowing movement of cycling. Oslo’s Onda Restaurant (2010–11), designed by Norwegian firm Alliance Arkitekter, is an undulating structure of durable, environmentally friendly local pine, combined with a simple, sheer glass façade and galvanized steel gratings, while Iceland’s PK Arkitektar has designed modern rural cottages with traditional timber walls and turf-covered roofs. In China, Wang Shu (b.1963) and Lu Wenyu (b.1966) mixed recycled materials and regional influences in their award-winning Ningbo Museum (2008).

Dynamic architecture

While the British Post Office Tower (1964) featured the world’s first revolving floor, the world’s first fully rotating high-rise building is the 15-storey Suite Vollard in Paraná, Brazil (opposite) opened in 2001, designed by Bruno de Franco. Each of the 11 floors is clad in double sheets of glass, tinted silver, gold or blue, which create spectacular effects as they rotate in opposite directions. Each floor can revolve 360 degrees in an hour. Following this concept, the Dynamic Tower (a.k.a. Da Vinci Tower) is a proposed 420-metre (1,378-ft), 80-floor skyscraper, designed by Italian-Israeli architect David Fisher (b.1949) for Dubai. As in the Suite Vollard, each floor is intended to rotate independently, with one full rotation every 90 minutes, constantly changing the shape of the tower. The Dynamic Tower will be the world’s first prefabricated skyscraper, with 90 per cent built off site in a factory; only the core of the tower will be built on site. Sourcing its power from onboard wind turbines and solar panels, it should produce enough surplus electricity to power five other similar-sized buildings in the area.