Shanghai Shimao International Plaza, China

The Shimao International Plaza (formerly known as Wanxiang International Plaza) is a luxurious hotel near the People's Square in central Shanghai, 60 storeys above ground and three underground. It is planned in the shape of an isosceles triangle. It has a total height of 246 m, 61 000 mm² floor area above ground and a roof mast reaching 333 m high. The main tower consists of eleven huge columns and three belt trusses, is a mega-frame with outrigger and concrete core structure. The ten-storey podium is a frame-shear wall system, which serves as a shopping mall. There is a two-storey public square covered with a glass roof of the same height as the podium, as shown in plan. The construction commenced in 1997 and was held off after the three-storey underground structure was finished in 1999. Construction resumed in 2001 under a new project title, by a new owner. The new owner requested significant changes to the architectural function: the upper part of the tower was changed into a five-star hotel, each floor above the 11th floor extended 1.5 m outward, which resulted in an increase of floor area of 17 000 m²; the diagonal steel bracings on three sides of the building were omitted; the top elevation of the roof mast was raised from 321 to 333 m; an additional floor was added to the public square area that was made a two-storey restaurant. The changes of architectural function to the underground floors required modifications and reinforcement as well. With enormous effort, the last version of the design document was issued in 2002 and the main structure was successfully completed in October, 2004.