Structural Studio

Fukuoka Daimyo Garden City, Fukuoka, Japan
Architect: Kume Sekkei + Junkenchiku (Urban Design Institute)
Structural Engineer: Kume Sekkei

Fukuoka Daimyo Garden City is a mixed-use redevelopment on the former Daimyo Elementary School site, delivered as part of the Tenjin area’s renewal and opened in 2023. The project is organized around a central public garden, with an office–hotel tower (B1–25F) paired with lower community and event volumes. Total floor area is approximately 91,423 m², with the tower rising to about 111 m to form a new landmark on Meiji-dori.

The structural concept combines steel framing with CFT (concrete-filled steel tube) members and an explicit damping strategy. The tower’s south façade is formed by a large inclined “skin frame” that works as an exterior braced system, collecting gravity and lateral actions and returning them to the core and foundations. High-strength steel (around 550 N/mm² class) is used for the primary built-up members, with plate thicknesses up to about 55 mm; core concrete strengths are in the Fc60–Fc75 range. Typical office bays are about 18 m × 7.2 m with deep steel beams (roughly H600–H900), while hotel floors tighten perimeter spans to match room planning (about 7.2 m down to 4.8 m). Seismic response is reduced using a mix of damping devices (including oil dampers, steel dampers, and buckling-restrained braces), and transfer / belt elements at the functional change level redistribute large in-plane forces from the inclined frame into the main diaphragm and core.

Urban and operational value is driven by the “garden-first” planning: the public open space draws pedestrian flow through the block and ties office, hotel, and community programs into a single precinct. Structurally, the exterior inclined frame helps keep interior planning efficient while making the load path legible to students—core, diaphragm collection, perimeter frame action, damping, and foundations all visible in one system. The mixed steel–CFT approach places material where it is most effective for stiffness, drift control, and constructability, supporting long-term adaptability for office tenancy and hotel operations.

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Hong Kong West Kowloon Station, Hong Kong, China
Architect: Andrew Bromberg at Aedas
Structural Engineer: Buro Happold (station and roof)

Hong Kong West Kowloon Station opened in 2018 as the Hong Kong terminus of the Guangzhou–Shenzhen–Hong Kong Express Rail Link. With about 400,000 m² of usable floor area on a footprint of roughly 10 ha, it is one of the largest below-grade rail stations in the world. The terminal reaches about 30 m below ground, with platforms and underpasses stacked beneath a sloping urban park and a 45 m high arrival hall that frames views of Victoria Harbour and the Hong Kong Island skyline.

The structural concept separates a robust underground box from a lightweight long-span roof. The buried station is a reinforced-concrete structure with thick diaphragm walls, slabs and cross-walls resisting soil and water pressure on reclaimed land. Above the concourse, a steel roof fans up and southwards in a series of warped ribs. Tapered steel arches and leaning columns work together as a three-dimensional frame; secondary members carry roughly 4,000 glass panels and metal decking while acting as in-plane collectors. The roof thrusts and unbalanced moments are resolved through inclined supports, concrete cores and deep transfer elements along the southern edge. Construction used top-down methods for the concrete box and balanced cantilever er****on for the roof, allowing large prefabricated steel assemblies to be lifted into place over the excavated station.

The station’s roof and landscape act as a civic platform rather than a conventional concourse cover. Sloping green terraces and paved ramps draw daylight deep into the hall, reducing daytime lighting demand and helping passengers orient visually toward the harbour. Compact track and platform layouts release more than 3 ha of surface as public park, tying directly into the West Kowloon Cultural District. The project demonstrates how long-span steel roofs, deep excavation and high-speed rail requirements can be combined into a single structural and urban gesture that manages crowd flows, border control and wayfinding while contributing usable open space to a dense waterfront district.

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