Fallen Woven Yarn | 奇想天蓋

This project is a tearoom designed and built in collaboration with a young architectural designer who had just graduated from the university. Suspended within the dim interior of a traditional townhouse, a delicate and ethereal canopy seems to float overhead.
The canopy consists of a series of steel compression rings, each with slightly varying diameters, suspended in sequence from the ceiling beams using thread. Each ring is hung with 100 equally spaced threads arranged uniformly along its circumference. Additional threads span between the rings, forming hyperbolic surfaces that create, depending on the angle of view, a three-dimensional mandala pattern floating in midair with a translucent, hovering effect.
In order to prevent the threads from sagging, the design intentionally increases the weight of the canopy and introduces tension by applying load only after all the threads are in place. Even so, with 100 perimeter threads and another 200 forming the symmetric interior mandala pattern, each steel ring is suspended by nearly 300 threads, resulting in an extremely highly indeterminate structure.
Maintaining consistent tension across all threads—so that not a single one appears loose—proved immensely challenging. No doubt the young designers came to understand firsthand the difficulty of controlling the flow of force. Yet, the space they created is remarkably beautiful.

Design and construction: Yui Matsmoto + Takuo Nagai Lab + Volunteer students from the University of Shiga Prefecture
Program: Tearoom
Year of completion: 2018
Photo by Kurome Photo Studio

大学を卒業しばかりの若い意匠設計者とデザイン・制作した茶室である。町屋の薄暗い空間に，やわらかい印象の天蓋が浮かんでいる。天蓋は，直径を少しずつ変えた鉄筋の圧縮リングを小屋梁から直列状に糸で吊っている。吊り糸は円周を100等分した位置で均等に配置した。また，内部にもリング同士の間に双曲面を作るように糸を張り，天蓋は，透けるような浮遊感とともに見る角度によって立体的な曼陀羅模様が浮かび上がるデザインとなっている。設計にあたり，糸が緩まないように天蓋の重量をなるべく重くすること，および全ての糸を配置した後に荷重をかけ張力を入れるなどの工夫を行っている。とは言え，外周の糸は100本，内部の曼陀羅模様（100本を左右周りに対称に配置）も合わせれば， 1段あたりの鉄筋を300本の糸で吊るす「大」不静定構造である。1本の糸さえも緩まないようにするため張力の調整は非常に苦労し，若者らは力の流れを制御する難しさを痛感したに違いないが，出来上がった空間は大変美しいものとなった。

設計・施工：松本悠以＋永井拓生研究室＋滋賀県立大学学生有志
用途：茶室
完成年：2018年
写真：黒目写真館