【正文】 A spacetruss hat structure is provided at the top of the building. 7. A similar space truss is located near the bottom of the building 8. The entire assembly is laterally supported at the base on twin steelplate tubes, because the shear stiffness of the outer tube goes to zero at the base of the building. Cellular structures A classic example of a cellular structure is the Sears Tower, Chicago, a bundled tube structure of nine separate tubes. While the Sears Tower contains nine nearly identical tubes, the basic structural system has special application for buildings of irregular shape, as the several tubes need not be similar in plan shape, It is not unmon that some of the individual tubes one of the strengths and one of the weaknesses of the system. This special weakness of this system, particularly in framed tubes, has to do with the concept of differential column shortening. The shortening of a column under load is given by the expression △=∑fL/E For buildings of 12 ft () floortofloor distances and an average pressive stress of 15 ksi (138MPa), the shortening of a column under load is 15 (12)(12)/29,000 or () per story. At 50 stories, the column will have shortened to in. (94mm) less than its unstressed length. Where one cell of a bundled tube system is, say, 50stories high and an adjacent cell is, say, 100stories high, those columns near the boundary between .the two systems need to have this differential deflection reconciled. Major structural work has been found to be needed at such locations. In at least one building, the Rialto Project, Melbourne, the structural engineer found it necessary to vertically prestress the lower height columns so as to reconcile the differential deflections of columns in close proximity with the posttensioning of the shorter column simulating the weight to be added on to adjacent, higher columns. 結(jié)構(gòu)系統(tǒng)抵抗橫向荷載 常用的結(jié)構(gòu)體系 與負載檢測成千上萬 kips ，很少有房的設(shè)計，高層建筑的過于復(fù)雜的想法。 the trusses are placed often at mechanical floors, mush to the disapproval of the designers of the mechanical systems. Nevertheless, as a costeffective structural system, the belt truss works well and will likely find continued approval from designers. Numerous studies have sought to optimize the location of these trusses, with the optimum location very dependent on the number of trusses provided. Experience would indicate, however, that the location of these trusses is provided by the optimization of mechanical systems and by aesthetic considerations, as the economics of the structural system is not highly sensitive to belt truss location. TubeinTube Structures The tubular framing system mobilizes every column in the exterior wall in resisting overturning and shearing forces. The term?tubeintube?is largely selfexplanatory in that a second ring of columns, the ring surrounding the central service core of the building, is used as an inner framed or braced tube. The purpose of the second tube is to increase resistance to over turning and to increase lateral stiffness. The tubes need not be of the same character。 忽略了一些概念，有關(guān)的材料嚴格的建設(shè)，最常用的結(jié)構(gòu)系統(tǒng)用于高層建筑可歸納如下： 1 .矩抗張。此外，在高建筑物，多數(shù)是由互動元素在三維陣列。 矩抗框架 也許，最常用的系統(tǒng)在低到中等高樓大廈，目前抗內(nèi)，特點是線性的橫向和縱向聯(lián)系成員基本上是在其關(guān)節(jié)僵硬。在高的高層建筑，該系統(tǒng)很可能會發(fā)現(xiàn)不合適的一個獨立的系統(tǒng)，這個，因為難以調(diào)動足夠的剛度下的側(cè)向力。 雖然使用結(jié)構(gòu)鋼支撐框架中是很常見，混凝土框架結(jié)構(gòu)更可能的較大規(guī)模的品種。限于狹隘傾覆，一個明顯的使用該系統(tǒng)，它具有必要的寬度，是在外墻建設(shè)，那里的要求是保持小窗戶。因為這些欄目的抵制側(cè)向力放在盡可能從 cancroids 的制度，但總的轉(zhuǎn)動慣量的增加和剛度是非常高的。然而，作為一個符合成本效益的結(jié)構(gòu)系統(tǒng)，帶桁架運作良好，并有可能找到繼續(xù)批準設(shè)計師。管子不必進行同一性質(zhì)，也就是說，一個管可以制定，而其他可能支撐。 核心互動結(jié)構(gòu) 核心的互動式結(jié)構(gòu)是一種特殊情況的筒中筒，其中兩個管耦合與某種形式的三維空間內(nèi)。 空間結(jié)構(gòu)支腿或桁架梁，連接內(nèi)胎的外管，位于往往在幾個層面的建設(shè)。 細胞結(jié)構(gòu) 一個典型的例子了蜂窩結(jié)構(gòu)的西爾斯大廈，芝加哥，捆綁筒結(jié)構(gòu)的 9 個獨立管。至少在一個建設(shè)，里亞托項目，墨爾本，結(jié)構(gòu)工程師認為有必要縱向預(yù)應(yīng)力低高度欄，以便核對鑒別撓度欄接近與后張的短欄模擬 重量要添加到相鄰，更高欄。 這一個特殊的弱點這一制度，特別是在管內(nèi)，已經(jīng)這樣做的概念差別柱縮短。 2 .兩個內(nèi)胎提供，每個三十一英尺（九點四米） 40英尺（一十二點二米） ，