Beijing 2008 Olympic Green Tennis CentreEdit profile
The new Beijing Olympic Tennis Centre is located on the western edge of the Forest Park, the vast landscaped park that is immediately adjacent to Beijing Olympic Green, the main site for the Olympic Games. The site of the tennis centre is embedded in a newly planted forest of trees on gentle slope that almost imperceptibly falls from its western boundary towards the lakes surrounding the central hill of Forest Park. The tennis centre is ordered by a series of four giant platforms that float about the ground. They arranged in a linear sequence that steps up against the slope from west to east, each having their own landscape order. A tree-lined circulation spine acts as a cross-axis to connect the platforms and is closed visually on small artificial hill to the east. The sequence of raised podiums allows the forest to permeate incisively from south to north, and at its highest level establishes a promontory to enjoy the panoramic view across Forest Park back to the National Stadium. These heroically scaled platforms of varying dimensions organise the venue into a series of programmatic clusters that provide an intimate scale for spectators’ activities and services above, and sufficient space to accommodate all the support accommodation and secured circulation below. The platform’s edges are defined by 3.6m high horizontal bands of concrete that act as deep beams to provide large openings and dramatic cantilevers for the varying points of entry, access and openings to the accommodation below. Spectators arrive at the western end of the venue and stroll up and across the four platforms: a low entry court with the 2000 seat number two court to the north and large landscaped forecourt to the south configured to allows future expansion to 10,000 seats and an area for events; the second platform of intermediate height accommodates eight match courts; the third and highest platform contains the 11,000 seat centre court and 4,000 seat number one court and features recessed landscaped courtyards that provide daylight and ventilation to the accommodation below. The fourth and final platform holds the six practices inscribed at ground level to provide direct access for players’ to their locker rooms and training facilities. The Tennis Centre is both clearly organised and memorable as well as having a symbolic and important centre court as the climax of the architectural composition. The Centre Court demonstrates a direct and elegant tectonic solution composed in twelve segments, approximately circular, with a concentric upper seating bowl and a lower bowl recessed into the platform with additional seats parallel to the court on the east and west. The raking surfaces of the bowl fold into a dramatically cantilevering roof structure that shades two thirds of the seats. At night the raking surfaces are back lit providing an important effect for night games - a giant lantern hovering of the platforms that rise through the forest canopy. The roof also integrates the court lighting which is joined by catwalk around the roof perimeter. The upper bowl and roof of the stadium is arranged around the expression of the twelve segments that have been tapered in alignment to the optimum sightlines, the effect being the introduction of twelve openings that interrupt the even surface of the bowl serve. This strategy organised through an understanding of bowl geometry provides a significant environmental and amenity purpose. While the alignment focuses attention to the field of play, the openings between the segments allow visual relief from the intense focus of the bowl, permit distant views of Forest Park and Olympic Green to be enjoyed across the duration of play, and allows for those arriving at the venue to engage with the spectators within. More importantly however, as the major tournaments are often held during the extreme conditions of summers’ peak, this interrupted form releases the heat that collects in the upper bowl and induces a slow cyclonic air flow which significantly contributes to reducing court level temperatures and increasing air movement to a more comfortable level for players and spectators alike. The natural ventilation strategy for the centre court however is the most important aspect of the project’s sustainability together with its extensive water/sewerage re-cycling systems. Other sustainable features employed include the use of a geothermal heat pump system to the main courts: a system which uses ground-source energy to heat and cool the court surfaces. Also, aAn advanced sewage treatment system allows for 100 percent of the tennis center's wastewater to be treated through membrane biological reactors (MBR) to remove contaminants allowing it to be used water the Centre’s landscape. Directness in the expression of the venue’s components allows a dialogue between the materiality and the activities and events. A strong architectural language is made with a restricted palette of materials – off-white insitu concrete, charcoal painted steel beams, perforated white aluminium sheet, insulated glazed in black anodised aluminium frames and precast concrete paving. The superstructure of the centre court features cantilevering wishbone raking tier beams constructed in precast concrete. The insitu plats, the structure holding the seats, simply span between the tiers beams and with the white perforated aluminium cladding form a mechanical services/basement ventilation plenum. The roof is constructed from fabricated tapering steel box beams which cantilever off the top of the raking tier beams. Each segment of the bowl and roof structure is independent. The lower seating bowl within the platform is a simple insitu concrete structure. The use of a regular figure for the bowl geometry allows a simple and more efficient structure than a less regular shape. From a rigorous analysis of context, programme and amenity, the Tennis Centre has arisen as an ensemble of components responding specifically to their circumstance. The architecture is not derivative from cultural or metaphoric associations. The formal distinction of the architecture is achieved within the expressive potential of its components articulated with a precise and efficient purpose.