CHINA

JINMAO TOWER

LOCATION: Shanghai,ChinaARCHITECT: Skidmore, Owings & Merrill

ANCIENT DETAILS:It was designed by theChicagofirm ofSkidmore, Owings & Merrill(SOM). Its postmodern form, whose complexity rises as it ascends, draws ontraditional Chinese architecturesuch as the tieredpagoda, gently stepping back to create a rhythmic pattern as it rises. Like thePetronas TowersinMalaysia, the building's proportions revolve around thenumber 8,associated with prosperityinChinese culture. The 88 floors (92 if the spire floors are counted) are divided into 16 segments, each of which is 1/8 shorter than the 16-story base. The tower is built around an octagon-shaped concreteshear wallcore surrounded by 8 exteriorcompositesuper columns and 8 exterior steel columns. Three sets of 8 two-story high outriggertrussesconnect the columns to the core at six of the floors to provide additional support.Thefoundationsrest on 1,062 high-capacity steel piles driven 83.5m (274ft) deep in the ground to compensate for poor upper-strata soil conditions. At the time of construction, these were the longest steel piles ever used for a land-based building. The piles are capped by a 4 m-thick concreteraft19.6m (64ft) underground. The basement's surroundingslurry wallis1 mthick,36 mhigh and568 mlong. It is composed of 20,500m3(720,000cuft) of reinforced concrete.The building employs an advancedstructural engineeringsystem ofwindandearthquake engineeringwhich fortify it against typhoonwinds of up to 200km/h (with the topswayingby a maximum of 75cm or 30in) andearthquakesof up to 7 on the Richter scale. The steel shafts haveshearjoints that act asshock absorbersto cushion the lateral forces imposed by winds and quakes. The swimming pool on the 57th floor is also said to act as a passivedamper.The exteriorcurtain wallis made of glass,stainless steel,aluminum, andgraniteand is crisscrossed by complexlattice work claddingmade of aluminum alloy pipes.

OPERATIONS:Official dedication was August 28, 1998, a date also chosen with the number 8 in mind. The building was fully operational in 1999. The Jin Mao Tower is owned by the China Jin Mao Group Co. Ltd (formerly China Shanghai Foreign Trade Centre Co. Ltd). It reportedly has a daily maintenance cost of 1 millionRMB(US$121,000).

The fourmechanical storiesforming the spire of the building are brightly illuminated at night.The building has 3 main entrances to thelobby: two for the office portion and one for the hotel. The basement has express elevators to the observation deck and a parking area for 600 vehicles and 7,500 bicycles. In total, 61Mitsubishielevators and 19 escalators carry visitors throughout the building. Levels 51, 52, and 8993 aremechanical floors, accessible only by service elevators.