1、学院(部): 土木建筑学院专业班级:学生姓名:指导教师: XXX 助教2012 年 06 月 02 日外文资料安徽理工大学毕业设计(论文)Anhui University Of Science and TechnologyAlthough there have been many advancements in building construction technology in general. Spectacular archievements have been made in the design and construction of ultrahigh-rise building
2、s.The early development of high-rise buildings began with structural steel framing.Reinforced concrete and stressed-skin tube systems have since been economically and competitively used in a number of structures for both residential and commercial purposes.The high-rise buildings ranging from 50 to
3、110 stories that are being built all over the United States are the result of innovations and development of new structual systems.Greater height entails increased column and beam sizes to make buildings more rigid so that under wind load they will not sway beyond an acceptable limit Excessive later
4、al sway may cause serious recurring damage to partitions, ceilings.and other architectural details. In addition,excessive sway may cause discomfort to the occupants of the building because their perception of such motion.Structural systems of reinforced concrete as well as steel take full advantageo
5、f inherent potential stiffness of the total building and therefore require additional stiffening to limit the sway.In a steel structure for example the economy can be defined in terms of the total average quantity of steel per square foot of floor area of the building Curve A in Fig .1 represents th
6、e average unit weight of a conventional frame with increasing numbers of stories. Curve B represents the average steel weight if the frame is protected from all lateral loads. The gap between the upper boundary and the lower boundary represents the premium for height for the traditional column-and-b
7、eam frame Structural engineers have developed structural systems with a view to eliminating this premium.Systems in steel. Tall buildings in steel developed as a result of several types of structural innovations. The innovations have been applied to the construction of both office and apartment buil
8、dings.Frame with rigid belt trusses. In order to tie the exterior columns of a frame structure to the interior vertical trusses a system of rigid belt trusses at mid-height and at the top of the building may be used. A good example of this system is the First Wisconsin Bank Building(1974) in Milwauk
9、ee.Framed tube. The maximum efficiency of the total structure of a tall building, for both strength and stiffness to resist wind load can be achieved only if all column element can be connected to each other in such a way that the entire building acts as a hollow tube or rigid box in projecting out
10、of the ground. This particular structural system was2probably used for the first time in the 43-story reinforced concrete DeWitt Chestnut Apartment Building in Chicago. The most significant use of this system is in the twin structural steel towers of the 110-story World Trade Center building in New
11、YorkColumn-diagonal truss tube. The exterior columns of a building can be spaced reasonably far apart and yet be made to work together as a tube by connecting them withdiagonal members interesting at the centre line of the columns and beams. This simple yet extremely efficient system was used for th
12、e first time on the John Hancock Centre in Chicago, using as much steel as is normally needed for a traditional 40-story building.Bundled tube With the continuing need for larger and taller buildings, the framed tube or the column-diagonal truss tube may be used in a bundled form to create larger tu
13、be envelopes while maintaining high efficiency. The 110-story Sears RoebuckHeadquarters Building in Chicago has nine tube bundled at the base of the building in three rows. Some of these individual tubes terminate at different heights of the building, demonstrating the unlimited architectural possib
14、ilities of this latest structural concept.The Sears tower, at a height of 1450 ft(442m), is the world s tallest building.Stressed-skin tube system. The tube structural system was developed for improvingthe resistance to lateral forces (wind and earthquake) and the control ofdrift (lateralbuilding mo
15、vement ) in high-rise building. The stressed-skin tube takes the tube system astep further. The development of the stressed-skin tube utilizes the fa?ade of the buildingas a structural element which acts with the framed tube, thus providing an efficient wayof resisting lateral loads in high-rise bui
16、ldings, and resulting incost-effectivecolumn-free interior space with a high ratio of net to gross floor area.Because of the contribution of the stressed-skin fa?ade, the framed members of the tube require less mass, and are thus lighter and less expensive. All the typical columns and spandrel beams
17、 are standard rolled shapes minimizing the use and cost of special built-up members. The depth requirement for the perimeter spandrel beams is also reduced, and the need for upset beams above floors, which would encroach on valuable space, is minimized. The structural system has been used on the 54-
18、story One Mellon Bank Center in Pittburgh.Systems in concrete. While tall buildings constructed of steel had an early start, development of tall buildings of reinforced concrete progressed at a fast enough rate to provide a competitive chanllenge to structural steel systems for both office and apart
19、ment buildings.Framed tube. As discussed above, the first framed tube concept for tall buildings3was used for the 43-story DeWitt Chestnut Apartment Building. In this building ,exterior columns were spaced at 5.5ft (1.68m) centers, and interior columns were used as needed to support the 8-in . -thic
20、k (20-m) flat-plate concrete slabs.Tube in tube. Another system in reinforced concrete for office buildings combines the traditional shear wall construction with an exterior framed tube. The system consists of an outer framed tube of very closely spaced columns and an interior rigid shear wall tube
21、enclosing the central service area. The system (Fig .2), known as the tube-in-tubesystem , made it possible to design the world s present tallest (714ft or 218m)lightweigconcrete building ( the 52-story One Shell Plaza Building in Houston) for the unit price of a traditional shear wall structure of
22、only 35 stories.Systems combining both concrete and steel have also been developed, an examleof which is the composite system developed by skidmore, Owings &Merril in which anexterior closely spaced framed tube inconcrete envelops an interior steel framing,thereby combining theadvantages ofboth rein
23、forced concrete and structural steelsystems. The 52-storyOne Shell Square Buildingin New Orleans is based on thissystem.Steelconstruction refers to a broad range ofbuilding construction in which steelplays theleading role. Most steel construction consists of large-scale buildings orengineering works
24、, withthe steel generally in the form of beams, girders, bars, plates,and other members shaped through the hot-rolled process. Despite the increased use of other materials, steel construction remained a major outlet for the steel industries of the U.S, U.K, U.S.S.R, Japan, West German, France, and o
25、ther steel producers in the 1970s. Early history. The history of steel construction begins paradoxically several decades before the introduction of the Bessemer and the Siemens-Martin (openj-hearth) processes made it possible to produce steel in quantities sufficient for structure use. Many of probl
26、ems of steel construction were studied earlier in connection with iron construction, which began with the Coalbrookdale Bridge, built in cast iron over the Severn River in England in 1777. This and subsequent iron bridge work, in addition to the construction of steam boilers and iron ship hulls , sp
27、urred the development of techniques for fabricating, designing, and jioning. The advantagesof iron over masonry lay in the much smaller amounts of material required. The truss form, based on the resistance of the triangle to deformation, long used in timber, was translated effectively into iron, wit
28、h cast iron being used for compression members-ie, those bearing the weight of direct loading-and wrought iron being used for tension members-ie, those bearing the pull of suspended4loading.The technique for passing iron, heated to the plastic state, between rolls to form flat and rounded bars, was
29、developed as early as 1800;by 1819 angle irons were rolled; and in 1849 the first I beams, 17.7 feet (5.4m) long , were fabricated as roof girders for a Paris railroad station.Two years later Joseph Paxton of England built the Crystal Palace for the London Exposition of 1851. He is said to have conc
30、eived the idea of cage construction-using relatively slender iron beams as a skeleton for the glass walls of a large, open structure. Resistance to wind forces in the Crystal palace was provided by diagonal iron rods. Two feature are particularly important in the history of metal construction; first
31、, the use of latticed girder, which are small trusses, a form first developed in timber bridges and other structures and translated into metal by Paxton ; and second, the joining of wrought-iron tension members and cast-iron compression members by means of rivets inserted while hot.In 1853 the first metal floor beams were rolled for the Cooper Union Building in New York. In the light of the principal market demand for iron beams at the time, it is not surprising that the Cooper Union beams close
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