By Jenny Jones
The building has four precast concrete walls that cantilever beyond the facade, recalling a lotus flower.
The shape of the Nan Tien Institute, a Buddhist tertiary educational center in Wollongong, Australia, was inspired by a lotus flower. Peter Bennetts
April 28, 2015—Rising from a former refuse tip in southeastern Australia, the Buddhist tertiary educational center known as the Nan Tien Institute (NTI) underscores the religion's belief that a new and healing experience can be created from a place of disuse and disintegration. Defined by four pods of curved and cantilevered precast concrete walls, the 6,000 m
building's shape was inspired by the lotus flower—a Buddhist symbol of purity and spiritual awakening. A great deal of structural detailing was necessary to effect the emblematic structure.
The NTI opened in March in the city of Wollongong, immediately south of Sydney. Designed by the Sydney offices of global architecture firm Woods Bagot and the Australian structural engineering firm Calibre Consulting, the center is the cornerstone of a master-planned campus that will eventually serve 3,000 students. It is located across a busy highway from the existing Nan Tien Temple, part of the Taiwanese Fo Guang Shan Buddhist order and one of the largest Buddhist temples in the southern hemisphere. A Woods Bagot-designed pedestrian bridge inspired by the High Line elevated park in New York City is being constructed across the highway to tie together the temple and campus.
Designed to accommodate 300 students, the NTI has three above-grade levels and a basement that houses parking, storage, and kitchen facilities. The center's ground floor is largely a public space, accommodating a central three-story cruciform atrium as well as a library, cafe, art gallery, and lecture halls. The two upper levels are arranged into the four pods, which house classrooms, informal learning spaces, and offices for the teachers. Interior bridges link the pods together above the ground floor and afford space for spontaneous discussions. "We wanted to create like a little campus within this one building," says Georgia Singleton, the director and global sector leader of education, health, and science at Woods Bagot. "It's really centered around movement and serendipity."
Four wing walls cantilever as much as 6.5 m from the building, creating the iconic lotus shape. Peter Bennetts
The center is founded on 400 mm
driven precast-concrete piles that extend up to 10 m to refusal. Mark Woodwell, the business development manager of the structures department of Calibre, says piles were ideal because they could be driven directly through the fill and buried refuse on the site without the need for excavation and disposal of the tip material. The refuse tip is covered by a gas drainage layer, a membrane, and a protective layer of fill. A spray-applied, water-based membrane between the ground and the building's basement slabs and retaining walls further protects the building from the gases released by the remaining refuse on the site. "Consideration of the structure detailing at the interfaces with the membrane and between the structure slabs, pile caps, and piles was required to maintain the integrity of the liquid boot membrane," Woodwell says.
The building is framed in reinforced-concrete banded slabs supported by columns and load-bearing walls. Woodwell says the building's key feature is the curved walls that bound the atrium and form the pods. These walls extend beyond the facade to form four seemingly freestanding wings, giving the building its lotus shape. The walls were originally designed to be 200 mm thick load-bearing, cast-in-place reinforced concrete, but the contractor suggested using precast construction to ensure a high-quality boarded finish, optimal joint layout, and color consistency. The change "required extensive development of the design to break the panels into sizes that could be transported by truck to the site and that were within the capacity of the site crane," Woodwell says.
The walls were divided into two sections and then broken into smaller precast concrete panels. All of the panels are approximately 3.5 m wide, the lower panels measuring roughly 7 m long and the upper ones measuring about 4 m long. Supported by a transfer floor at ground level and penetrated by many windows and open arches, the walls carry the vertical load within the building. But the precast wall design, with a staggered joint pattern, disrupted the load paths, requiring careful detailing to maintain the load paths around the numerous wall openings, Woodwell says.
The building’s cruciform atrium is bounded by four pods and capped by a roof that appears to float above the space. Peter Bennetts
The 265 mm thick wing walls that extend beyond the facade also presented challenges. Supported at the ground floor on one edge and at the first floor and roof on the other edge, these walls are divided into thirds and cantilever up to 6.5 m outward from the building to form two fully exposed, freestanding faces. The largest wing wall is 14.5 m tall and 6 m wide. Dowels were inserted into the centers of the panel joints to ensure vertical continuity. However, dowels could not be inserted into the vertical joints in the horizontal direction. So Calibre engineers developed a "detail of introducing posttensioning ducts into the panels and then stressing the panels horizontally back into the building," Woodwell explains. "That gave us the flexural capacity to let the walls cantilever in the wind in two directions."
The building's roof is also noteworthy. In the atrium, a continuous glass skylight lines the edges of the roof, separating the main roof structure from the walls to create the sensation that the roof itself is floating, Woodwell explains. To achieve this illusion, the roof is framed by steel beams that span up to 7 m across the atrium. The beams step up at the skylight to disappear from view. "It creates the sense that the skylight is quite high and the roof floats in the middle of it," Woodwell notes. The underside of the roof and the bridges connecting the pods are clad in oak timber, providing a sense of warmth and acoustic dampening to the interior space. An oculus measuring 2 m in diameter sits in the center of the roof.
The interior is further enhanced by large operable windows that allow sunlight to flood the space and provide natural ventilation. Aluminum fins in a terra-cotta color adorn the windows to reduce solar gain. Fixed to vertical spindles, each fin is rotated slightly from the one below it, giving the facade a rippled appearance. "The aluminum fins are quite organic and have an orange color, which reflects the terra cotta of the temple on the other side of the freeway," Singleton notes. Aluminum panels of the same color also clad the building.
Terra-cotta-colored aluminum fins on the windows provide solar control and give the facade a rippled appearance. Peter Bennetts
Construction of the NTI began in late 2013. The building was completed and officially opened during a ceremony lead by Australian Prime Minister Tony Abbott in March. The center, like the adjacent temple, is expected to attract students and visitors from around the world. "The building is already an icon with the landscape of the institute and the city of Wollongong," Singleton says.