Shanghai Qi Zhong Tennis Center is expected to become a world-class tennis center, comparable with the Wimbledon in London and the Roland Garros in Paris.

In 2003, local government invited international design companies to tender for the design of the proposed tennis facility in the southwest of Shanghai.

The winning bid came from world-renowned Japanese architect Mitsuru Senda and his company Environment Design Institute, an architectural and landscape firm specializing in children's environments including schools, museums, child centers, hospitals, sports facilities, parks, play structures, and housing.

One of the key design features that won EDI the bid was the stunning eight-piece magnolia roof, which resembles a flower blooming when opening. The roof enables the stadium to host both indoor and outdoor tennis events.

"We aimed to symbolize the city's development with this movable roof system for the main stadium in this sports center, which is a first for sports stadiums in China," Senda said.

The movable roof system appears to be extremely simple: the roof opens like a flower. When the roof opens, many sunshades protect the occupants of the stadium, creating the effect of shade given by trees.

It offers a comfortable environment for people gathering both inside and outside of the stadium.

A plaza is set up around the main stadium, containing many shops and cafes. Broad steps are provided between the deck and courts for qualifying events and the place will be used for resting.

A rich green garden belt surrounds the site so that visitors can enjoy seasonal flowers.

The stadium is Colosseum-shaped, which promotes a sense of unity between the players and the spectators. In the summer, cool air is directed down from the top of the building to the floor of the round stadium. In the winter, air warmed by the ducting system under spectators' seats will keep sports fans comfortable.

The design allows for comfortable environments with minimal maintenance costs. The structure of the stadium, called the "tension ring structure" creates a strong and reliable Colosseum-shape.

The movable roof of main stadium consists of eight petals and each petal rotates around its own fulcrum simultaneously.

Under the petals, there is a round truss, which has an inverted triangle section, to support the petal structures. Each petal can be moved by one fulcrum and three rails, creating a cantilevered beam. Despite their apparent lightness, these structures are strong enough to withstand gale force winds.

Fantastic facilities

At night the tennis center is brilliantly illuminated. The external form of the stadium is outlined by lights, with additional lightplay provided by a an the center's sophisticated lighting system. The flower stadium will be remembered with pleasure by both players and visitors, for its beauty and world class facilities.

The Shanghai government and the Qi Zhong Group of Companies have funded the building of the Tennis Center.

The tender for project to manage the research, testing and technical adaptations for the stadium design was won by the Shanghai Institute of Architectural Design and Research.

It worked with independent building contractors to oversee construction, and also managed and designed phase two of the Qi Zhong Tennis Center for construction of the remaining tennis courts and clubhouse.

Architect Zhang Chen and engineer Lin Yingru led the SIADR team.

Both have worked on many of Shanghai's largest structures and sporting facilities. They traveled to Roland Garros to gather ideas for the Qi Zhong stadium.

"We were impressed with the beautiful surroundings and deep sense of tennis history," Lin said.

Back in Shanghai, the team was faced with a number of challenges to make the design a reality.

"We spent millions of RMB and one year researching whether this kind of roof was actually feasible. There was no other project like this that could act as a reference point. We also researched whether the stadium could withstand earthquakes, typhoons and other environmental impacts by creating a model to simulate these effects," Zhang said.

"Each part of the roof was built on the ground first. The method of testing each of the petal structures on the ground is similar to that used by China Aerospace, where each roof piece must pass a test before it is elevated to its position for installation."

Other companies involved in the Tennis Center's construction include China Construction Third Bureau, Jiangnan Heavy Industry Co Ltd and Shanghai Mechanical Construction Co Ltd.

The Tennis Center covers a total area of 338,836 square meters, of which 85,000 square meters are made up of structures.

Adaptable arena

The center court stadium features 30,649 square meters of construction. It has four floors, with a total height of 40 meters above ground level. The center court features the "magnolia flower" steel roof with eight petal-shaped pieces (each petal weighs two tons). The magnolia is Shanghai's city flower.

The stadium can be adapted for other international events such as basketball, volleyball, ping pong, and gymnastics.

During the Tennis Masters Cup event, there will be a retail zone and public eating/drinking areas outside the stadium.

The Center Court seats 15,000 people. The court is surrounded by 30 permanent rows of seats (12,000).

Another 3,000 VIP seats are found in the 26 deluxe skyboxes and courtside box seats.

These seats will have access to private hospitality lounges and dining areas.

There are rooms for players and administrators on the first floor, which are not accessible to spectators. The stadium also contains 20 broadcasting rooms at the highest level of the venue, which will allow simultaneous television coverage by 20 different media groups.

Space is also reserved inside the inner court ring for broadcasting equipment. Given the circular shape of Center Court, there is little to block views, which provide excellent sight lines for TV broadcasting.

Shuttle buses between the site and various downtown locations will be arranged for the Tennis Masters Cup events. In addition, there will be 993 parking spaces.