Kyorin University S.Matsuda Memorial Arena

A new gymnasium "Forest Arena" that harmonizes with the surrounding rich natural environment has been constructed on a new site adjacent to Kyorin University Mitaka Campus, which includes a university and hospital. The gymnasium not only functions as an arena, but is also required to have symbolism and function as a 3,000 person capacity memorial lecture hall where entrance ceremonies and graduation ceremonies can be held. Various rooms are arranged around the arena with the building open to the surrounding lush natural environment, to cultivate the health in mind and body of all those involved in medical treatment, including students, etc. The building was arranged north-south with the flow line from the existing campus and vista of the forest on the north side of the site. A large opening was provided behind the stage to incorporate the borrowed landscape of the forest into the space. A structural steel "tree-like cross-arch framework" is provided above the Arena, which includes the spectator seating. Ventilation windows are incorporated above the openings, so that the prevailing south to north wind at the site is brought into the building. A Forest Arena has been produced where activities can be performed while experiencing nature, to cultivate heart, mind, and body within the natural environment. The 43.2 m long span roof that covers the spectator seating is a tree-like cross-arch framework that reproduces a forest through a fusion of structure and architecture. This was realized using computational design to determine the rise and structural steel dimensions to optimize the mass of the framework, and a fractal structural steel framework design that used an algorithm "L-system", which generates plants as a motif. The framework has a layered composition consisting of bottom chord members, inclined members, and top chord members, with high side lights provided between the top and bottom layers. This not only has a borrowed light function, but also achieves an energy-efficient scheme with gravity ventilation and natural aeration by providing ventilation windows on the top. The diverse activities of the students are stimulated by the Forest Arena framework, which is a fusion of HVAC and structure. The external wall on the south side is fair-faced concrete using timber formwork to impart the motif of the texture of the bark of a tree. The wall surfaces in the central three bays are engraved with words meaning Truth, Goodness, and Beauty, for the founding spirit of the university. The wall surfaces on the east, west, and north sides have ribs and windows as vertical slits, creating an external appearance in harmony with the vertical trees.