Hangzhou International Expo Center is located in Qianjiang Century City, Xiaoshan District, Hangzhou city. It consists of five floors above ground and two floors underground. With a total construction area of 850000 square meters, it is a complex of five business forms, including conference, exhibition, hotel, business and office building. The main part of the project is a frame structure composed of concrete-filled steel tubular columns and large-span steel trusses. The steel structure of the roof garden is a curved steel reticulated shell and a single-layer spherical shell. The auxiliary office building is a cast-in-situ concrete frame shear wall structure. The total amount of steel structure is more than 140000 tons, equivalent to 3.5 bird's nests; The on-site welding seam of steel structure reaches 50000 meters; The construction covers all forms of steel structure buildings.