What is the shape of the main building of Japan Pavilion in Hanover World Expo?

At the Hanover World Expo, a number of ecological pavilions with the concept of "sustainable development" stood out. Among them, Japan Pavilion is the largest and lightest paper building in architectural history. Its skeleton is all made up of recycled paper tubes, and the walls and roof are covered with a translucent recycled paper film. The simple arch structure of the main hall is made up of 440 paper tubes with a diameter of 12.5 cm, which embodies the image of the barrier in traditional Japanese houses, namely wooden paper doors and windows. The soothing architectural curved surface is made of fabric and paper film, and the roof and wall are integrated. The ceiling surface is a translucent film made of fabric and paper plastic materials, which can withstand all kinds of weather tests and allow natural light to enter the room at the same time, forming a soft indoor environment.

This kind of paper itself is recycled paper. After the World Expo, he shipped all the paper back to Japan to recycle it as a teaching material for Japanese students, so it means that nothing can be recycled at the World Expo and everything can be taken back.