土木工程专业英语 段兵延.doc

Lesson 4 Tall BuildingAlthough there have been many advancements in building construction technology in general, spectacular achievements have been made in the design and construction of ultrahigh-rise buildings虽然在建筑施工技术中，总的来说已经有了许多进步，但是在超高层建筑的设计和施工中也取得了惊人的成就。The early development of high-rise buildings began with structural steel framing高层建筑的早期发展始于结构的钢框架。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从那以后，钢筋混凝土和薄壳筒体体系就被竞相经济地用在了许多民用和商用结构中。The high-rise buildings ranging from 50 to 110 stories that are being built all over the United States are the result of innovations and development of new structural systems美国各地正在修建的50110层的高层建筑是新的结构体系改革和发展的结果。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更大的高度需要增加柱和梁的尺寸来使建筑物的刚性更大，以便于它们在风荷载作用下不会倾斜到允许的范围之外。Excessive lateral sway may cause serious recurring damage to partitions, ceilings, and other architectural details过分的水平倾斜将导致隔板、天花板和其他建筑物细部的严重的复发性破坏。In addition, excessive sway may cause discomfort to the occupants of the building because of their perception of such motion此外，过分的倾斜还可能导致建筑物内部居住者的不适，因为他们感觉到了这种运动。Structural systems of reinforced concrete, as well as steel, take full advantage of the inherent potential stiffness of the total building and therefore do not require additional stiffening to limit the sway钢筋混凝土和钢结构系统充分利用了整个建筑的固有的潜在的刚度，因此不需要额外的加强板来限制倾斜。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.比如，在钢结构中，可以根据建筑物的每平方英尺楼板面积所需要钢材的总平均数量来限定经济。Curve A in Fig.1 represents the average unit weight of a conventional frame with increasing numbers of stories图1中的曲线A描绘的是传统框架随着增加的楼层数的平均单位重量。Curve B represents the average steel weight if the frame is protected from all lateral loads曲线B描绘的是在框架不受任何横向荷载时平均钢材重量。The gap between the upper boundary and the lower boundary represents the premium for height for the traditional column-and-beam frame上下边界之间的间隙描绘的是传统柱梁框架由高度带来的额外费用。Structural engineers have developed structural systems with a view to eliminating this premium为了消除这种额外费用，结构工程师们已经发展了一些结构体系。Tall buildings in steel developed as a result of several types of structural innovations.用钢材修建的高层建筑是作为几种类型的结构的创新的结果而发展起来的。The innovations have been applied to the construction of both office and apartment buildings这种创新已经被用在办公楼和公寓大楼的施工当中。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.为了把框架结构的外柱连接到内部垂直桁架上，可以在建筑的中部和顶部设置刚性带状桁架系统。A good example of this system is the First Wisconsin Bank Building (1974) in Milwaukee这种体系的一个好的例子就是密尔沃基市的威斯康星第一银行大楼。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 elements 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 of the ground只有当所有的柱子以这样一种方式（即整个建筑作为一个中空的筒体或刚性的盒子突出于地面上）互相连接在一起时，才能获得高层建筑的整体结构对于抵抗风荷载的强度和刚度的最大功效。This particular structural system was probably used for the first time in the 43-story reinforced concrete DeWitt Chestnut Apartment Building in ChicagoThe most significant use of this system is in the twin structural steel towers of the 1l0-story World Trade Center building in New York这种特殊的结构体系第一次使用可能是在芝加哥的这幢43层钢筋混凝土公寓大楼中。这种体系的最有意义的使用是在纽约的110层世贸中心大厦的结构钢双塔中。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 with diagonal members intersecting at the center line of the columns and beams建筑的外柱可相隔适当远的距离，它们还能被作成一个筒体一起起作用，通过把它们和对角的构件在柱和梁的中线上交叉而连接在一起。This simple yet extremely efficient system was used for the first time on the John Hancock Center in Chicago，using as much steel as is normally needed for a traditional 40-story building这种简单但非常有效的体系第一次使用是在芝加哥的John Hancock中心大楼中，它用了和传统40层楼所正常需要的一样多的钢筋。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 tube envelopes while maintaining high efficiency随着对更大更高的建筑的不断需要，框筒或对顶柱桁架筒体可能被用在捆绑的形式中以形成更大的筒体外壳，同时又保持了高效力。The 110-story Sears Roebuck Headquarters Building in Chicago has nine tubes, bundled at the base of the building in three rows芝加哥的110层Sears Roebuck Headquarters大楼有9个筒体，在大楼的基础部位被捆成了三排。Some of these individual tubes terminate at different heights of the building，demonstrating the unlimited architectural possibilities of this latest structural concept这些独立的筒体中的一些在大楼的不同高度处中止，这是最新的结构概念的不受限制的建筑上的可能性的一个例证。The Sears tower，at a height of 1450 ft (442 m) ，is the worlds tallest buildingThe tube structural system was developed for improving the resistance to lateral forces (wind or earthquake) and the control of drift (1ateral building movement) in high-rise building筒体结构体系被发展起来是为了提高高层建筑对侧向荷载（风和地震）的抵抗，以及对建筑的侧向位移的控制。The stressed-skin tube takes the tube system a step further薄壳筒体使筒体体系又向前迈进了一步。The development of the stressed-skin tube utilizes the facade of the building as a structural element which acts with the framed tube, thus providing an efficient way of resisting lateral loads in high-rise buildings，and resulting in cost-effective column-free interior space with a high ratio of net to gross floor area薄壳筒体的进步是利用建筑的正面（墙或板）作为与框筒共同起作用的结构构件，为高层建筑抵抗侧向荷载提供了一个有效的途径，而且可获得节省成本、不设柱子、使用面积与建筑面积之比很高的室内空间。Because of the contribution of the stressed-skin facade，the framed members of the tube require 1ess mass，and are thus lighter and less expensive因为薄壳立面的作用，筒体的框架构件需要量就更少，因此就更轻更便宜。All the typical columns and spandrel beams are standard rolled shapes，minimizing the use and cost of special built-up members所有代表性的柱和窗下墙的墙托梁都是标准的轧制形式，这可以使特殊的组合构件的用量和成本降到最低。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周围窗下墙托梁的厚度要求也就降低了，将侵占有用空间的楼板上的梁的需求也减到了最少。The structural system has been used on the 54-story One Mellon Bank Center in PittsburghWhile 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 challenge to structural steel systems for both office and apartment buildings当早期有了用钢筋修建的高层建筑的时候，钢筋混凝土的高层建筑也在以一个很快的速度发展，从而形成了对钢结构系统的激烈挑战，不论是在办公大楼还是在公寓大楼的使用中。Framed tube 框筒As discussed above，the first framed tube concept for tall buildings was used for the 43-story DeWitt Chestnut Apartment Building如前所讨论的，框筒的概念第一次被用于高层建筑是在43层的DeWitt Chestnut 公寓大楼中。In this building，exterior columns were spaced at 5.5-ft (1.68-m) centers, and interior columns were used as needed to support the 8-in. -thick (20-cm) flat-plate concrete slabs在这幢建筑中，外柱中线间隔了1.68m，内柱被用来支撑20cm厚的混凝土平板。Another system in reinforced concrete for office buildings combines the traditional shear wall construction with an exterior framed tube办公大楼中用钢筋混凝土的另一种系统是把传统的剪力墙结构和一个外部的框筒结合起来。The system consists of an outer framed tube of very closely spaced columns and an interior rigid shear wall tube enclosing the central service area该体系由间距很小的柱子构成的外框筒和围绕中心设备区的刚性剪力墙内筒组成。The system (Fig.2), known as the tube-in-tube system，made it possible to design the worlds present tallest (714 ft or 218m) lightweight concrete building (the 52-story One Shell Plaza Building in Houston) for the unit price of a traditional shear wall structure of only 35 stories被称为筒中筒的这种系统，使设计出目前世界上最高的轻质混凝土大楼成为可能，并且这幢大楼的单位价格仅是传统的35层剪力墙结构的单位价格。Systems combining both concrete