Modern Tall Building Cities West vs East Introduction to Tall Building Structures CIVL 101 History and Practice of Civil Engineering Dr. C.M. Chan Department of Civil Engineering 27 November 2006 Chicago New York 1 2 Modern Tall Building Cities West vs East Modern Tall Building Cities West vs East Taipei Kuala Lumpar 3 New York West vs East Any difference? 4
Statistics of the world s tallest buildings (2005) In Asia In Mainland In HK Tallest commercial buildings First 10 First 100 8 47 3 16 2 8 Tallest residential buildings First 10 8 0 4 First 100 68 1 46 Tallest buildings under construction First 10 9 4 3 First 100 58 15 11 Note: A high-rise building is defined by Emporis Corp. (www.emporis.com/en/) as a building 35 m or greater in height. 5 6 Hong Kong - the world s s center of tall buildings Hong Kong has the world s highest population density Hong Kong - the world s s center of tall buildings Hong Kong has many world class buildings of complex shape using complicated structural systems 7 8
Challenges of Building Design in Hong Kong Large-scale development of clusters of tall residential buildings Challenges of Building Design in Hong Kong Enormous financial investments and relatively short design time 9 10 Challenges of Building Design in Hong Kong Demand for the best value for money - minimum cost design, maximum structural efficiency and usable floor area Average flat unit of 600 ft 2 costs ~ HK$ 1.8 M (@ HK$ 3,000/ft 2 ) A more luxury flat unit of 1500 ft 2 costs ~ HK$ 15 M (@ HK$ 10,000/ft 2 ) Top class rental office of 10000 ft 2 ~ HK$ 700,000/month (@ HK$ 70/ft 2 ) Tall buildings are closely related to the growth of the city Their developments are due to - economic growth - human ego to build higher - the natural response to dense population - scarcity of land in urban areas - high land costs - technological advancements 11 12
The world s first 10 tallest buildings 420 Two International Finance Center Taipei 101 How do we measure height? Council on Tall Buildings & Urban Habitat measured from the sidewalk level of the main entrance to the structural top of the building includes spires Excludes television antennas, radio antennas, and flag poles 381 384 391 420 508 13 14 Which is the Tallest? Tall Building Evolution 1,707 ft (520m) Top of Antenna 1667ft (508m) Top of Spire The world s s tallest structure in the ancient time 1,450ft (442m) Roof 1,483 ft (452m) Top of Spire 1470ft (448m) Roof 1,230ft (375m) Roof The Great Pyramid of Cheops, 481 ft (146m) in height World s tallest structure from 2580 BC to 1307 AD Relatively tall, but also very bulky 15 16
Tallest structures in the Middle Ages World s tallest structure in the time of Industrial Revolution - 300 m Eiffel Tower, 1889 in Paris - built for the 100th anniversary of the French Revolution and for an exhibition to celebrate French technical achievement - greatest use of wrought iron, a new construction at the time 404 ft Salisbury Cathedral, 1265 Tallest building in UK for over 600 years 557 ft Sagrada Familia, Barcelona, 1812 by Antonio Gaudi Gothic cathedrals represent human s desire to reach God and act as the most important symbol in towns 17 18 What do they have in common? What is a Building? Council on Tall Buildings & Urban Habitat A building is a structure that has floors and is designed for residential, business, or manufacturing. They are all inhabitable! 19 20
What is a tall building? Council on Tall Buildings & Urban Habitat A building is deemed tall when its design, use or operation is influenced by some aspect of tallness. Tall Building Evolution Modern tall buildings are made possible due to the three greatest technological advancements 1. Invention of elevators (by Otis in 1852). 2. Invention of new construction materials, e.g. steel (by William Kelly in 1847), reinforced concrete (by Joseph Monier in 1849). composite materials (in 20th century). 3. Invention of innovative structural forms. 21 22 Why y do tall buildings stand? 23 24
Wind-induced Motions Wind is a more critical issue in the design of tall buildings. The design of most tall buildings is in fact controlled by serviceability wind drift and motion criteria. Across-wind vortex shedding 25 26 Earthquake loads environmental load actions due to movement of the earth crusts. This is however not a critical issue in tall buildings Highrise Behaviour A tall building in a global sense behaves as if a cantilever stick to resist vertical gravity and transverse loads Fault forming Different types of faulting 27 28
1. Stacking effect of gravity loads 2. Effect of horizontal loads G G W G 2G W h W G G 3G 4G W W h h h 2W 3W 4W Overturning Moment 10Wh = W 4h+ W 3h + W 2h+ W h Gravity load effect increases linearly with building height Lateral shear load varies linearly with height, but overturning moment varies quadratically with height 29 30 Why y do tall buildings stand? From the structural engineer s s viewpoint, a building is considered as tall when its design is affected by the lateral loading due to wind or earthquake rather than by vertical gravity loads. 31 32
Evolution of Structural Systems Evolution of Structural Systems A rough classification can be made with respect to effectiveness in resisting lateral loads Structural systems Moment resisting frame systems Braced frames, shear wall systems Tubular systems framed tubes, trussed tubes, bundled tubes Outrigger braced systems Hybrid systems 33 34 HSBC Headquarters Structural Forms of Some Notable Buildings in Hong Kong 35 Steel Mega-frame 179m 43 Stories - Office Completed 1985 Architect: Foster & Partners Engineer: Ove Arup & Partners One of the most expensive buildings in Hong Kong 36
Gravity load action Wind load action Bank of China Tower Composite Space Truss 369m 70 Stories - Office Composite Space Truss Completed 1989 Architect: I. M. Pei & Partners Engineer: Leslie E. Robertson Associates Noted as one of the most outstanding achievement in modern architecture and building structures 37 38 Central Plaza New Structural Form for Super Tall Buildings Outrigger Braced System Concrete Tubular System 374 M 78 Stories - Office Concrete Tube Completed 1992 Architect: Ng Chun Man Architect Engineer: Ove Arup and Partner Currently the world s tallest concrete building 39 40
Advantage of Outrigger Braced System Two International Finance Centre OUTRIGGER BRACED STRUCTURE TUBE-IN-TUBE - 6M COLUMN GRID 41 42 Two International Finance Centre What s s Next Hong Kong s s Tallest building? International Commerce Centre Concrete Core + Steel Outrigger + Composite Columns 420m 88 Stories Office Completed in 2003 Architect: Cesar Pelli / Rocco Engineer: Ove Arup & Partners The tallest building in Hong Kong 2 IFC 43 44
International Commerce Centre the world s fourth tallest building International Commerce Centre Concrete Core + Outrigger Braced System 484m 118 Stories Office & Hotel Under construction, expected completion 2007 Architect: Kohn, Pedersen and Fox Assoc. & Wong and Ouyang (HK) Ltd. Engineer: Ove Arup & Partners Expected to be Hong Kong s tallest building and the world s fourth tallest building 45 46 Hotel Zone Lateral Stability System International Commerce Centre - Construction as of October 2006 Office Zone 4-level steel outriggers Reinforced concrete core High stiffness reinforced concrete mega columns Change in structural form at the hotel levels 47 48
What s s Next China Tallest building? Shanghai World Financial Center International Commerce Centre - Construction as of November 2006 Composite Space Truss 492 m 101 stories Office & Hotel Under construction, expected completion 2007 Architect: Kohn, Pedersen and Fox Assoc. & East China Architectural Design & Research Institute Engineer: Leslie E. Robertson Assoc. Expected to be China s tallest building and the world s third tallest building 49 50 What s s the World s s Next Tallest Building? Burj Dubai Burj Dubai - Construction as of August 2006 Coupled Reinforced Concrete System Over 800 m Over 160 stories Office & residential Under construction, expected completion 2008 Architect: Skidmore O Engineer: Leslie E. Robertson Assoc. Expected to be China s tallest building and the world s third tallest building 51 52