- Tube (structure)
structural engineering, the tube is the name given to the systems where in order to resist lateral loads (wind, seismic, etc.) a building is designed to act like a three-dimensional hollow tube, hence the name, cantilevered perpendicular to the ground. The system was introduced by Fazlur Rahman Khan while at Skidmore, Owings and Merrill's (SOM) Chicago office. The first example of the tube’s use is the 43-story Khan-designed DeWitt-Chestnut Apartment buildingin Chicago, Illinois.
The system can be constructed using
steel, concrete, or composite construction (the discrete use of both steel and concrete). It can be used for office, apartment, and mixed-use buildings. Most buildings in excess of 40 stories constructed in the United States from the period after World War IIto the 1990s were of this structural type. It is slowly being overtaken by the use of core-supportedtype structures.
The tube system concept is based on the idea that a building can be designed to resist lateral loads by designing it as a hollow
cantileverperpendicular to the ground. In the simplest incarnation of the tube, the perimeter of the exterior consists of closely spaced columns that are tied together with deep spandrel beams through moment connections. This assembly of columns and beams forms a rigid frame that amounts to a dense and strong structural wall along the exterior of the building.
This exterior framing is designed sufficiently strong to resist all lateral loads on the building, thereby allowing the interior of the building to be simply framed for gravity loads. Interior columns are comparatively few and located at the core. The distance between the exterior and the core frames is spanned with beams or trusses and intentionally left column-free. This maximizes the effectiveness of the perimeter tube by transferring some of the gravity loads within the structure to it and increases its ability to resist overturning due to lateral loads.
After 1965, a new structural system of framed tubes appeared in
skyscraper design and construction. The Bangladeshi engineer Fazlur Khandefined the framed tube structure as "a three dimensional space structure composed of three, four, or possibly more 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 by cantilevering from the foundation." [Cite web| title = Evolution of Concrete Skyscrapers| accessdate = 2007-05-14| url = http://www.civenv.unimelb.edu.au/ejse/Archives/Fulltext/200101/01/20010101.htm ] Closely spaced interconnected exterior columns form the tube. Horizontal loads, for example wind, are supported by the structure as a whole. About half the exterior surface is available for windows. Framed tubes allow fewer interior columns, and so create more usable floor space. Where larger openings like garage doors are required, the tube frame must be interrupted, with transfer girders used to maintain structural integrity.
The first building to apply the tube-frame construction was in the DeWitt-Chestnut apartment building which Khan designed in
Chicago. This laid the foundations for the tube structures of many other later skyscrapers, as can been seen in the construction of the World Trade Center.
From its inception, the tube has been varied to suit different structural requirements:
This is the simplest incarnation of the tube. It can take a variety of floor plan shapes from square and rectangular, circular, and freeform. The most notable examples are the Aon Center and the destroyed
World Trade Centertowers.
Also known as the "braced tube" it is similar to the simple tube, but with comparatively fewer and farther-spaced exterior columns. Bracing is introduced along the exterior walls to compensate for the fewer columns by tying them together. The most notable examples are the
John Hancock Center, the Citigroup Center, and the Bank of China Tower.
Instead of one tube, a building consists of several tubes tied together to resist the lateral forces. Such buildings have interior columns along the perimeters of the tubes when they fall within the building envelop. Notable examples include
Sears Towerand One Magnificent Mile.
A varied category of structures were the basic concept of the tube is used, but supplemented by other structural support methods. One example is 780 Third Avenue on Manhattan, a 50-story concrete frame office building. Its plan and height-to-width ratios as well as column spacing exceeded the criteria necessary to create an effective tube structure. A concrete braced tube (created by infilling window openings with concrete panels)supplemented with
shear walls within an off-center core laterally stabilize the building.
Wikimedia Foundation. 2010.
См. также в других словарях:
Tube — may refer to:Electronics *vacuum tube, a component of electronics *cathode ray tube, a common component of electronics such as televisions and other displays *Tube, An expansion bus on the BBC Micro computer *Nokia 5800 Tube , A mobile phoneFood… … Wikipedia
Tube-chair — La Tube Chair, de son nom original Tubo est une création de 1969 du designer italien Joe Colombo. Sommaire 1 Histoire de la création 2 Fabrication … Wikipédia en Français
Tube chair — La Tube Chair, de son nom original Tubo est une création de 1969 du designer italien Joe Colombo. Sommaire 1 Histoire de la création 2 Fabrication … Wikipédia en Français
Tube electronique — Tube électronique Un tube électronique (vacuum tube en américain ou thermionic valve en anglais), également appelé tube à vide ou même lampe, est un composant électronique actif, généralement utilisé comme amplificateur de signal. Le tube à vide… … Wikipédia en Français
Tube à vide — Tube électronique Un tube électronique (vacuum tube en américain ou thermionic valve en anglais), également appelé tube à vide ou même lampe, est un composant électronique actif, généralement utilisé comme amplificateur de signal. Le tube à vide… … Wikipédia en Français
tube — ► NOUN 1) a long, hollow cylinder for conveying or holding liquids or gases. 2) a flexible metal or plastic container sealed at one end and having a cap at the other. 3) a hollow cylindrical organ or structure in an animal or plant. 4) Brit.… … English terms dictionary
Tube — A long hollow cylinder. There are many tube like structures in the human body, such as the auditory tube (Eustachian tube) in the ear. * * * 1. A hollow cylindrical structure or canal. 2. A hollow cylinder or pipe. SYN: tuba [TA]. [L. tubus]… … Medical dictionary
Tube électronique — Un tube électronique (vacuum tube en américain ou thermionic valve en anglais), également appelé tube à vide ou même lampe, est un composant électronique actif, généralement utilisé comme amplificateur de signal. Le tube à vide redresseur ou… … Wikipédia en Français
tube-shaped structure — noun (anatomy) any hollow cylindrical body structure • Syn: ↑tube • Derivationally related forms: ↑tubal (for: ↑tube), ↑tube (for: ↑ … Useful english dictionary
Tube de Krasnikov — Un tube de Krasnikov est un mécanisme spéculatif permettant le voyage spatial. Il s agit d utiliser des tunnels superluminiques. La structure est semblable à un trou de ver et a été proposée par le physicien russe Serguei Krasnikov en 1995… … Wikipédia en Français