On 20th of March, the main structure of the 2019 Beijing international horticultural Expo performance center project undertaken by BCEG has been completed, successfully achieving the target. This giant multicoloured butterfly finally "spread its wings", and the effect of "flower blooming butterfly dance" in the Expo Park is perfect.

The performance center is one of the core buildings of 2019 international horticultural Expo park. The covered area is 4500 square meters and the total steel for installation is 1182 tons. The roof of steel structure is supported by 26 cantilevered umbrella-shape steel trusses, which shows the shape of "butterfly wing spread" under the tension of cable strands. The ETFE film includes dark red, dark green, orange, blue, red, green six kinds of color for its external use.