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Building a Gold Medal Pool
Because of its many complex details, the Goodwill Games Pool in East Meadow, New York, is considered by some swimmers to be the best pool in the country
If you could design the perfect swimmer's body, it wouldn't b that different from the perfect building to house swimming pool. Both would have high strength-to-weight ratio. Both would minimize surface area-in the case f the swimmer, to reduce drag; in the case of the building, to lower heat loss and gain. Both would efficiently consume the rsources put into them. And both would b flexible.
new natatorium in New York State embodies these ideals. The Goodwill Games Swimming and Diving Complex at Eisenhower Park in East Meadow, New York, was designed b the office of Richard Dattner Architect for the 1998 games. (Today, the pool is used for recreational swimming, training, and swim meets.) make the opening of the games, it was imperative that the building b constructed in 18 months; the budget was set at $26 million. Although the building was designed to seat 4,000, it was unlikely that the venue would play host to such large audience very often. "We decided that rather than overbuild to achieve such capacity," says Richard Dattner, FAIA, "we would devise way to open u the building to increase seating capacity only when it was necessary." he construction budget would b invested, Dattner adds, in "systems that would diminish the long-term costs f operations and maintenance-things like stainless-steel ductwork-and incorporating the most up-to-date competition pool features."
Structural system and building envelope
he swimming and diving complex was built n gently sloping site, a grade change that naturally rendered the building handicap-accessible t both the pool and spectators levels and allowed much of the structure to b built into the earth, decreasing its apparent mass.
The profile of the building is also made less daunting b it semi cylindrical shape, formed b steel-arch structural systemm, designed b Dattnr and engineer EdDePaola of Severud Associates, that has several advantages over standard post-and-truss construction. While it reduces the buildings exterior exposed roof area to minimize heat loss and gain, it still allows fr the height required for competitive diving; the highest point n the lower chord of the truss is located almost exactly over the 10-meter diving platform. There are n columns to obscure spectators' sightlines. cast-in-place concrete buttress supports the horizontal thrust and deadweight load at both ends of the trusses, which are triangular in section, with the apex pointing down. Long-span metal decking crosses the trusses' top chords and between the trusses themselves without intermediate structural support. Round steel sections used for the trusses also help prevent condensation (which leads to corrosion) b creating better ventilation than theflat surfaces of steel angles and I-sections would, and b discouraging the settling of dust, which attracts and holds moisture.
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The eight trusses that form the roof of the building were prefabricated in three sections, s they could b trucked to the site on flatbed trailers. Construction could not have bn simpler: the truss sections n each end were raised and secured to the buttresses; the middlesection was hoisted between the end trusses and bolted into place; and intermediate trusses were placed between the arches for lateral stability. he construction manager, Tishman Construction Corporation, helped the architects design false work that rolled along the bottom chord of the intermediate trusses, allwing work n ducts, lighting and electrical systems, roofing, and piping to take place bv while construction n the pool proceeded below. Says Dattner, "We had to work on both to keep the construction n schedule, and because it is just too dangerous to have one crew working over another, we constructed the false work."
The base of the building is masonry, laid in alternating bands of light and dark tan. Light-colored prefabricated insulated metalpanels were installed bv the masonry, with an insulated metal roof over the trusses. Inside, most of the end walls and the exposed ceiling between the trusses are covered b perforated metal panels filled with noise-dampening material that is enclosed in moisture-proof material; an water that might become trapped inside would reduce the panels' effectiveness in absorbing sound.
Most of the rooms throughout the bui1ding feature energy-saving fluorescent lighting. In the pool area, metal-halide lamps are housed in open-bottomed glass shades, which provide direct-indirect light distribution. Most of the light is reflected down to the pool, and the remainder is refracted up onto the ceiling. At the top of the exterior walls in the pool area, narrow band of translucent, insulated fiberglass panels is used to admit daylight; narrow barrel vault of the material was installed at the roofs highest point to bring daylight into the center of the building.
avoid building for maximum capacity, the architects devised method of opening up the building to accommodate temporary seating. Between each pair of buttresses n the south side of the pool where there is n permanent seating, walls made of glass doors can slide to one side. Metal wall panels bv the doors can then b pivoted upward until they are horizontal, creating n opening 30 ft wide b 19 feet high where bleachers can b installed. Permanent stretched-fabric sunshades protect spectators.
h swimming pool structure was mad of gunite (; -)-concrete sprayed at high pressure directly onto the earth over reinforcing steel cage, with little or n extra framework. Pools can also b mad with formed-in-place concrete or with braced, heavy steel walls installd around the perimeter of concrete floor slab. Gunite was possible here because the soil n the site had high concentration of naturally compacted sand, says Dattne. It was economical, since the contractor was ab1e to dig cavity for the pool and the accompanying trenching for utilities with great dea1 of accuracy, spraying the concrete without the expense of constructing formwork. The 12-inch-thick walls were then trowel-finished with cementitious waterproofing material and covered with ceramic tile.
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Pool mechanical systems
Swimming pool buildings are notoriously difficult to air-condition because they are saturated with humidity. Water an condense n an cold surface-ducts, windows and curtain-wall systems, roof decking-causing drops, corrosion, and, in the winter, falling ice. For the Goodwill Games complex the architect used system designed especially for swimming pool buildings to reduce humidity and recover energy from heated air. Water condenses in units located near the ceiling of the building; the heat recovered during the condensation process is circu1ated to the basement and run through heat exchanger to preheat the pool water. Ai inside the building is constantly circu1ated nt only to ensure that moist air reaches the condensers but also to avoid the build-up f chlorine fumes.
Water flows to gutters around the pool perimeter, where trash is caught b vr grates, and continues n to primary filter mad f stainless-steel mesh that, collects an other large matter. It is then run under high pressure through tanks filled with sand and treated with chlorine tablets the size of hockey pucks before being returned to the pool. (Tablets are easier to handle than liquid chlorine, which also has limited shelf life.)
The racing section of the pool is 25 meters wide b 53 meter long and n b divided into an numbr of configurations for different programs. divide the pool, there are n-b-25-meter movab1 bulkheads-made of large metal and fiberglass tanks that span the pool and rest n the gutters-can b towed into place b two people using ropes n each end.
The shallow end of the pool is covered b nine-by-25-meter fiberglass platform. Scissor jacks beneath the floor can raise or lower this end of the pool in matter f minutes, using shaft fitted with worm gear and driven b two synchronized motors inside the pool equipment room. The floor can b used in man ways; people in submersible wheelchairs, for example, can enter the pool at n height and then be lowered to another level for their activities. For safetys sake, the hanging depth of this portion of the pool is indicated b an electronic display board mounted n nearby wall.
