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Lecture 2 : FORM ACTIVE 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 Zubizuri ("white bridge") | Bilbao, Spain • Santiago Calatrava. "in 1997
Form Active Structure System نظـــــــــــام الشكل النشــــــــــط • • • • •
منشآت تقاوم القوى بتشكيلها نظام متكامل ال يسمح بتدخل أى أنظمة أخرى نظام مرن يسهل فكه وتركيبه يستخدم عادة لتغطية البحور الكبيرة يتسم بالصراحة اإلنشائية ألنها تظهر علي واجهة المبنى وتؤثر بجميع أنواعها على التشكيل العام له
Steel & tensioned fabric
Millennium Dome - Richard Rogers London
Lecture 2. Form Active system
Structure system Form Active system
Vector Active system
1
Cables system
Bulk Active system
Surface Active system
Vertical Structure system
Form Active system
Tents system
Air Supported system
Arch System
1
Single Layers
1
Exterior Supports
1
Unpressurized interior
1
Foundation Arch
2
Double Layers
2
Interior Supports
2
In pressurized Interior
2
Continues Arch
3
Double Curvatures Arch & Cables
3
Tents with arches
3
Buttressed Arches
4
Flying tents
4
Tied Arch
Lecture 2. Form Active system
Lecture 2. Form Active system
Check: www.horstberger.com/web.me.com_horstberger2/Welcome.html
Catenary for loading that is uniform across the curved length of the cable
Lecture 2. Form Active system
The depth of the sag of a catenary structure determines the horizontal ( inward) thrust that is generated ; the less the sag , the greater the thrust
Lecture 2. Form Active system
The cables structures are capable of enormous spans The sag to span ratio is a primary structural design consideration . • Cable forces • Length • Diameter all depends on this proportion
• Cable forces are proportional to sag
inversely
• As the cable length decreases its required diameter increases
Lecture 2. Form Active system
• For a single load applied at mid-span , the optimum sag is 50 % of the span • For a uniformly loaded parabolic cable , the optimum sag is approximately 33 % of the span • Most cables used for building roof structures have sag to span ration 1:8 to 1:10
Lecture 2. Form Active system
Funicular suspension structures may be divided into 3 categories :
1
Single Curvature
They consists of two or more parallel cables spanning between primary supports .
2
Double Cable
3
Double Curvature
Lecture 2. Form Active system
Cable Cables • Made from mild steel . High strength steel ( drawn carbon steel ) , stainless steel , polyester . • Structural cables are made of series of small strands twisted or bound together to form a much larger cable
Lecture 2. Form Active system
Formالكابلـى Activeلنظام Structure اCableSystem System
Lecture 2. Form Active system
A
Bridges
The ancient rope suspension bridge ( early example have been identified in China , India and South America ) is the precedent for singular curvature structures . This kind of bridge of such flexibility had a problem as travelers move across , its shape changed in response to the moving load
Carrick-a-Rede Rope Bridge, Northern Ireland Lecture 2. Form Active system
Hanging Bridge at Thenmala, India Consists of a single twisted bamboo rope spanning 200m
Findley’s Stiffened deck ( The Chain Bridge ) • It was a key development in the evolution of the suspension bridge • It spanned 61 m over Jacobs Creek in Union town , Pennsylvania • The iron chain prevented the bridge from changing shape under moving loads Two or more towers support a pair of main suspension cables from which vertical secondary cables suspend the deck which carries the road way
Jacobs-creek-bridge , 1801 Lecture 2. Form Active system
The Golden Gate Bridge – San Francisco Bay • It was the longest suspension bridge span in the world when it was completed during the year 1937. • It incorporated a trussed deck for stiffness • The depth to span ratio of 1:168 was still much shallower .An unanticipated lateral rippling effect ( even in moderate winds / necessitated adding an additional 4700 tons of lateral bracing underneath along the entire length )
The Golden Gate Bridge - San Francisco Bay Lecture 2. Form Active system
Suspension bridge load paths Lecture 2. Form Active system
Failure Example : Tacoma Narrow Bridge ,1940
Ever since the Tacoma Narrows collapse , AERODYNAMIC behavior has been a concern for suspension bridge designers throughout the world Lecture 2. Form Active system
Clear span evolution in suspension bridge
Lecture 2. Form Active system
Dubai Mile-Long Arch Bridge
Fwfowle
FWFOWLE drew its inspiration from the city’s rivers & near-by sand dunes. The result is an elegant arched bridge that as built will be worlds largest & tallest spanning (arch bridge). Lecture 2. Form Active system
النظام الكابلـىCable System
Lecture 2. Form Active system
1
Single Curvature suspension
Burgo Paper Milll • The bridge like roof structure, used to house paper manufacturing machinery.
• Covers 7992 m2 center span 163 m
• The structure spanned in the longer direction (it is typically more economical to span in the shortest direction in order to allow further additions for housing new production lines parallel to the original while still maintaining a column free central area.
• Each end cantilevered an additional 43m
Lecture 2. Form Active system
The concrete supports [50 m] were rigid frames which provided the required lateral stability perpendicular to the span
Burgo Paper Mill – Italy – 1962 Lecture 2. Form Active system
PierLuigi Nervi
• A long clear span was achieved in this high rise building
• in order to leave the civic plaza (Marquette Plaza) below free from obstructions as well as to eliminate columns. • the building was designed in 2 parts :
1.
2.
Very large underground secure area for receiving and processing large amounts of money . 10 storey office block
With open plaza underneath for only entry lobby and end supports. • the office block spanned 82.3 m across the plaza
• two end service towers containing stairs , toilets , service elevators and mechanical spaces
Federal reserve bank – 1973 -Minneapolis Lecture 2. Form Active system
G. Birkerts and associates
Lecture 2. Form Active system
Lecture 2. Form Active system
• It is a combination of ingenious planning and expressive architecture. • Compact plan and short passenger waling distances • The pylons are spaced at 12 m for a column – free concourse space of 46 * 183 m • It presents integrity between form and function
Dulles Terminal Building- Washington, 1958-62 Lecture 2. Form Active system
Eero Saarinen
Parallel caternary suspended pairs of 25 mm diameter steel cables 3 m apart with precast concrete panels spanning between them.
Lecture 2. Form Active system
The roof is supported by a row of concrete pylons 12.2 m apart on each side .
Lecture 2. Form Active system
Lecture 2. Form Active system
• During construction sandbags were temporarily distributed on the precast decking in order to achieve the design curvature of the cables. • Once the desired curvature was achieved ,concrete was poured around the cables
Dulles Terminal Building- Washington, 1958-62 Lecture 2. Form Active system
Eero Saarinen
Lecture 2. Form Active system
تجميع عناصر الخدمات في المبنى واالستفادة منها تشكيليا. استخدام الصواري والكابالت المعدنية
Laboratories & Corporate Facilities , Richard Rogers . New Jersey Lecture 2. Form Active system
Inmos Micro Processor Factory , Richard Rogers Lecture 2. Form Active system
Lecture 2. Form Active system
Renault Distribution Centre Swindon, UK, 1980-1982
Lecture 2. Form Active system
. Norman Foster
Funicular suspension structures may be divided into 3 categories :
1
Single Curvature
2
Double Cable
They are similar to single curvature structure with addition of stabilizing cables below the primary suspension ones to resist wind lift.
3
Double Curvature
Lecture 2. Form Active system
Lecture 2. Form Active system
• An example of using opposing double cables to reinforce fabric roofs • The main terminal great hall is the largest tensile roof structure enclosing a single space in the world .
• Fabric was chosen for lightness and speed of erection as well as for aesthetic reasons . Denver airport terminal geodesic net of fabric roof
Denver International Airport Terminal Lecture 2. Form Active system
• Alluding to the surrounding snowcapped rocky mountains , the peaks are created by 34 masts placed in pairs 45 m apart with 18 .3 m between each pair .
Bradburn and associates
• The fabric sag between the peaks to span 63 m across the great hall
• The roof is double layer of fabric both made of Teflon coated fiberglass, • The 7 mm thick outer layer is the primary structural layer while the inner one provides an additional acoustical barrier and creates an air space to reduce heat loss
Lecture 2. Form Active system
• It has 63 m diameter ; huge concrete compression ring and a center tension rig to support the gravity load • Uplift forces are resisted by a similar pattern of stabilizing cables from the compression ring to upper tension ring . The opposing pairs of cables and two center tension sings are separated by vertical struts .
Utica auditorium , 1959 –New York Lecture 2. Form Active system
Funicular suspension structures may be divided into 3 categories :
1
Single Curvature
2
Double Cable
3
Double Curvature
They are anticlastic saddle shape where stabilizing cables running in a perpendicular direction pull downward to prevent wind lift Lecture 2. Form Active system
Lecture 2. Form Active system
النظام الكابلـىCable System
Lecture 2. Form Active system
النظام الكابلـىCable System
Lecture 2. Form Active system
Lecture 2. Form Active system
النظام الكابلـىCable System
Lecture 2. Form Active system
Lecture 2. Form Active system
• One of the most expressive examples of a suspension structure . • There is a clear distinction between the compression supporting arch and the tensile supported roof • The saddle shaped roof responds to the structural forces which shaped it in addition to the spatial needs of enclosed 5500 seats • Allows a generous amounts of glazing above the seating providing day lighting from all directions
Raleigh Arena Lecture 2. Form Active system
Ralerigh ; Deitrick and Nowicki
• The primary cables span 90m between the arches where their diameter ranges between 18-32 mm , they are spaces 1.8 m intervals . • The secondary cables opposite direction intending to reduce wind lift , diameter ranges between 12-18 mm & also spaced 1.8 m
Raleigh Arena Lecture 2. Form Active system
Ralerigh ; Deitrick and Nowicki
•The form longboat of the building was determined by a combination of structural , aesthetic and structural considerations
• The oval plan permits optimal seating with the majority of 2900 spectators near the middle
• The Convex lateral curvature prevents reflected noise from focusing ( a problem inherent in dome and other vaulted forms ) • The great parabolic arc spans 73 m
• Arch curvature reverses into a 12.2 m cantilever to emphasize the entrance
The very large ice hockey arena at Yale , 1958 Lecture 2. Form Active system
Eero Saarinen
The very large ice hockey arena at Yale , 1958 Lecture 2. Form Active system
Eero Saarinen
The arena holds 13,291 ,now primarily used for ice hockey, futsal and basketball
Yoyogi National Gymnasiums for Tokyo Olympics Lecture 2. Form Active system
Kenzo Tange
National Gymnasiums for Tokyo Olympics Lecture 2. Form Active system
Kenzo Tange
• A sports stadium covered a hyperbolic الكابلـى النظامwith Cable System parabolic roof consisting of a steel cable net suspended from a concrete perimeter ring .
• The perimeter columns serve only to support the compression ring . • The maximum cable span is 135 m . Cable paths are arranged in a 6 m grid with 15 mm
Calgary Saddled dome -Canada - 1983 Lecture 2. Form Active system
Jan Bobrowski and partners .
Lecture 2. Form Active system
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Thank you for your attention
Theories of Architecture [ 2 ] FA 400 .4.5 . Fall 2014 Faculty of Fine Arts . Department of Architecture Alexandria University A.Prof Dr .Ebtissam M.Farid Moustapha Associate professor