Perched on the Rokko Mountain in Kobe, the Rokko Shidare Observatory is a unique landmark that not only takes in spectacular views, but also provides a place to experience the natural energy and beauty of the Rokko Mountain. From inception to completion, Arup provided geometric and structural engineering and environmental design services to bring this project into reality.
Defining the geometry of beauty
The key visual feature of the observatory is the 16m diameter meshed dome that provides partial shelter against the weather. The 'half-skin' dome of interlocking steel pipes comprises a tessellation of triangles and hexagons, shifted out-of plane and woven-in, so the global structure is self-supporting.
Arup broke down the complex geometry and developed a computer solver program – Shift Frame Geometry–to manipulate and accurately define the complex shift geometry. To construct the dome, Arup exported the geometrical data of individual members and connection locations directly to the fabricator, along with three-dimensional models indicating the precise locations of each individual member.
16m diameter of dome
100,000visitors per year
A destination in its own right
The beguiling, natural aesthetic of the 16m-diameter structure will be enjoyed by the 100,000 people who visit the observatory each year. The integration of natural energy to passively control the observatory environment- a concept conceived by architect Hiroshi Sambuchi- visitors in summer will feel the cooling influence of the blocks of ice from water paddies frozen during the winter and stored below ground to naturally cool the observatory. And winter itself will be particularly spectacular: the mesh will transform itself into a myriad of delicate ice crystals, for which Rokko is famous.
3rd Kobe city urban design award