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Lecture 6: Vertical system
Theories of Architecture [ 3 ] FA 400 .4.5 . Fall 2014 Faculty of Fine Arts . Department of Architecture Alexandria University A.Prof Dr .Ebtissam M.Farid Moustapha Associate professor
.5نظام اإلنشاء الرأسي للمبانى العالية
)Vertical Structure System ( High-Rise Buildings يحتاج هذا النوع إلى استمرارية في العناصر اإلنشائية لتلقى األحمال من األدوار المختلفة ونقلها إلى األرض خالل العناصر الرأسية ويمكن أيضا تدعيم هذه العناصر بعمل شكاالت متقاطعة على مسافات مختلفة لحماية المبنى من الرياح واألحمال الجانبية Lateral Loadsوهذا النظام اإلنشائي من الممكن أن يكون: Direct loading System – 1نظام تحميل مباشر – 2نظام تحميل غير مباشر Indirect loading System
Lecture 6. Vertical system
Buildings between (23 m to 150 m) high are considered high-rises. Buildings taller than (150 m) are classified as skyscrapers.
Sky-scraping construction is a method that has always been an ideal means of displaying power and influence in the community
Lecture 6. Vertical system
The first high-rise buildings were constructed in the United States in the 1880s. They arose in urban
areas where increased land prices and great population densities created a demand for buildings that rose vertically rather than spread horizontally, thus occupying less precious land area.
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
High-rise buildings were made practicable by the use of steel structural frames and glass exterior shearing. By the mid-20th century, such buildings had become a standard feature of the architectural landscape in most countries in the world.
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Multistory building tall enough to require the use of a system of mechanical vertical transportation such as elevators as the skyscraper is a very tall high-rise building.
Lecture 6. Vertical system
• From a business point of view : Business activities need to be close to each other • From a touristic community point of view : It forms prestige symbols , distinctive land marks Hotels and commercial city centers . • High cost of land and limited space ( Tokyo , Hongkong ,Rio de Janeiro , etc.. )
Lecture 6. Vertical system
• From a business point of view : Business activities need to be close to each other • From a touristic community point of view : It forms prestige symbols , distinctive land marks Hotels and commercial city centers . • High cost of land and limited space ( Tokyo , Hongkong ,Rio de Janeiro , etc.. )
Lecture 6. Vertical system
• Putting intense pressure on the available landscape . • Increase the risk , safety hazards and constitute an easy target incase of war and terrorism
Lecture 6. Vertical system
Lecture 6. Vertical system
• Vertical Loads ( Gravity ) both live and dead • Other : Temperature differential
Lecture 6. Vertical system
The structural system of a high-rise building must resist both gravity and lateral
loads, due to phenomena such as wind and earthquake.
As the height of the building increases, the lateral loads gradually dominate the structural design. Lecture 6. Vertical system
• Lateral Loads ; wind and earthquake
Lecture 6. Vertical system
Lecture 6. Vertical system
Gherkin .London .Norman foster
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Design challenge ; selection of proper innovative systems
Lecture 6. Vertical system
Lecture 6. Vertical system
1.Wall and pier structure ( shear wall )
2. Rigid frames ( steel / RC) 3. Frame and Core systems ( rigid core RC or braced steel frames ) 4. Frames with exterior bracing ; trussed frames 5. Belt and outrigger truss frames with framed core 6. Tubular frames ( single tube – tube within tube – bundled tube ) 7. Mega structural frames 8. Cantilever , suspension
Lecture 6. Vertical system
Typical arrangement of shear walls
First used in 1940, may be described as vertical, cantilevered beams, which resist lateral wind and seismic loads acting on a building transmitted to them by the floor diaphragms.
Stabilizing elements are integrated into the vertical cores that house circulation and mechanical systems in tall buildings.
Lecture 6. Vertical system
They should be formed as closed elements, approximately square or cylindrical, with openings into the core kept to a minimum. A single core servicing an entire building should be located at the center of the building. Simple core structures can be used in buildings as high as 35 to 40 stories.
Lecture 6. Vertical system
Lecture 6. Vertical system
In buildings with more than one core, the cores should be located symmetrically in the building plan so as to provide balanced resistance under lateral loads from any direction.
Lecture 6. Vertical system
Cores typically comprise approximately 20%–25% of the total floor area of a high-rise building.
Cantilever , suspension Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
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Architect : Ponti – Fornaroli – Rosselli – Valtolina – DellOrto Engineer :Arturo Danusso – Pier Luigi Nervi Number of storeys : 32 Floor plan : 18* 68 m Height : 127 m Central corridor giving access to offices narrow toward the end
Lecture 6. Vertical system
Central towers are tapered from top to base
Towers are connected across the central corridors at each level by strong beam to improve buckling and bending resistance
Lecture 6. Vertical system
RC structure composed of 2 twin towers to resist the lateral resistance
Triangular tubes at both ends for bilateral resistance
Tower and tubes also support gravity load . The gravity load of towers improves the lateral stability against overturning
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Location : Facing Milan central station across a major urban plaza
Architect :Bae and Walter Betz 22 story – 144 m height
• Purpose to create a landmark for Munich and a unique architectural statement for the bank
• Structure 4 tubular concrete towers which supports 15 floors above and 6 floors suspended below . • The 4 towers combined with a platform form a mega frame to resist gravity and lateral loads .
• 4 Towers include exit stairs in pre-stressed concrete tubes of D=7m and wall thickness 60 cm + additional 5th tower
Lecture 6. Vertical system
Lecture 6. Vertical system
Architect : Paul Scheider Floor plan 16*32 m Height : 44 m 12 Story
• Located at the boundaries between the old and new banking district of Dusseldorf , • Has 2 story podiums to allow drive in bank at street level . • Free standing service core supports the pedestrian bridge and makes the link to the office floors . • second stairs and bath core located at the far end of the building providing undivided and flexible office spaces . • curtain wall manufactured of insulated sandwiched panels
Lecture 6. Vertical system
• Structure consists of RC ; 2 rows of squared cantilevered columns supported cantilever beams and concrete floor slabs .
Architect : Harry Seidler Floor plan 12*30 m Height : 38m 15 Story
- Has moveable exterior blinds for sun control giving the faรงade an ever changing appearance ( sunny days ; horizontal for optimum sun protection and cloudy days ; they are in lowered position ) - Location provides view over Sydney harbor and nearby botanical garden . - 2 story showroom with mezzanine floor is located on the ground floor above 4 story underground parking garage . - The office floor feature elevators / stairs / bathrooms on one end and an exit stairs at the opposite end providing flexible office floors .
Lecture 6. Vertical system
- The structure consists of RC , 2 rows of wall shape cantilever columns support cantilever slabs .The columns resists both gravity and lateral loads
Moment frames consists of one or more portals with columns joint to beams by moment resistant connections that transmit bending deformation from columns to beams and vice versa
Multi-bay deformation under lateral and gravity loads • Careful orientation of columns in order to achieve proper strength and stiffness to resist lateral load in both orthogonal directions • Columns orientation should provide symmetry of stiffness in both direction to prevent torsion
Lecture 6. Vertical system
Lecture 6. Vertical system
In concrete construction, core walls already intended to enclose these other building systems can easily be designed to also act as shear walls, in many cases with no increase in size. In steel construction, core structures are usually designed as braced frames.
Lecture 6. Vertical system
Building in Portland, Oregon
Architect : Pietro Belluschi •
It is a clear expression of a steel moment frame and a model for many subsequent buildings .
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The first double glazed aluminum curtain wall of simple elegance .
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First building to use heat pumps for efficient air conditioning, use double paned glass ,use air conditioning and flush curtain wall design
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The building is a compelling testimony of Belushi ‘s philosophy of simplicity
Lecture 6. Vertical system
Architect : Mies Van der Rohe and Philip Johnson Floor plan 26*43 m Height 160m 38 story •
The building exemplifies Mies philosophy of “Baukunst” ( art and craft of building ) with great attention to detail and proportion.
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Structure module 8.5m module
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Skin provides a visual cap
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Most of the structure is concealed behind the curtain wall which eliminates thermal stress due to outside temperature variations ; an important Factor in tall structure .
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Steel moment frame is embedded in concrete to provide protection and added stiffness
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Core walls have diagonal bracing up to the 29th floor for additional wind bracing .
Lecture 6. Vertical system
Architect Hentrich and Petchniggg
Lecture 6. Vertical system
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3 slabs in a composition with efficient circulation and good lighting for all offices that are never more than 7 m from the window .
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The central block contains the service core as the tallest block houses mechanical and elevators equipment In the top floors of 25 story tower .
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Glass Curtain wall facades
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Columns are made of steel pipes ( 7 x 4.2 m )
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The pristine design combining American Know hoe with European sophistication stands as an icon of the modern movement in Europe
• A framed tube structure is a new addition to the structural systems. Khan is generally credited with its invention in the 1960s. • Frames tubes are a variation of moment frames , braced frames, or shear walls, joined at or near their edges to form a vertical tube-like structural system capable of resisting lateral forces in any direction , wrapping the building with a wall of closely Spaced columns and short spandrel beams .
FT without interior core
FT with interior core
FT with internal belt and top truss for additional stiffness
• A major challenge of FT is the high cost of numerous moment resistant joints between closely spaced columns and beams Lecture 6. Vertical system
Dr.Fazlur Rehman Khan
• A 43-story reinforced concrete tower designed by Dr.Fazlur Rehman Khan and his colleagues at Skidmore, Owings & Merrill (SOM).
• Because of its great relative strength and stiffness, the tubular form immediately became a standard in high-rise design. • The revolutionary framed-tube structural system was first seen
Lecture 6. Vertical system
Architect :Eero Saarinnen • Framed tubes are expressed as triangular extrusions on the upper floor and diamond shaped on the ground floor including mechanical ducts and pipes , • Concrete floors span between the walls of a central core and the framed tube providing column free donut shape floor space for flexible use . • The articulation of top and bottom of the façade emphasizes the most prominent part of the building a strategy often use for the design of tall buildings .
Lecture 6. Vertical system
Architect : Minoru yamasaki • •
110 story tower 50000 employee and 80000 visitor daily
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Both towers in diagonal juxtaposition were vertical extrusions of square plans with very closely spaced steel columns
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2 story mechanical spaces distributed in 1/3 intervals
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FT structure consists of 56 box steel columns on each façade joint at each floor by spandrel beams with moment resistant connections ,,this vierendeel frame make from prefab elements
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The wall thickens increase from top to bottom in response to increasing loads
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The core columns are designed to carry gravity load only Framed tube resist both lateral and gravity load
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Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
• Core structures can also be enhanced structurally with the addition of bracing in the form of “hat” trusses. Hat trusses involve the perimeter • Columns of the building in resisting lateral loads, thus improving the overall performance of the building. Such trusses may influence the design of the building facade or the location of mechanical floors. • Columns at the perimeter of the building may also increase in size with this system. • Core-interactive structures are suitable for buildings up to approximately 55 stories in height.
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system
Vertical Element selection criteria Element Shear wall
Advantages •
Good for apartment buildings / hotels
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Very stiff , good for wind resistance
Challenges •
Inflexible for future changes
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Stiffness increases seismic forces
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Must remain in future changes
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Too flexible for tall buildings
(Wall and pier structure )
Cantilever ( core system )
Moment frame
Braced Frame
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Flexible planning around the cantilever
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Ductile, much like a tree trunk
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Most flexible, good for office buildings
Expensive
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Ductile , absorbs seismic force
Tall structure needs additional stiffening
More flexible than Shear wall Very stiff , good for wind resistance
Lecture 6. Vertical system
Less flexible than moment frame
Lecture 6. Vertical system
Lecture 6. Vertical system
Lecture 6. Vertical system