河南理工大学本科毕业设计 中文翻译
strength or solidness of the structure. This apparent safety may be more important than honestly expressing the building’s structure, because the untrained viewer cannot distinguish between real and perceived safety.
The building designer needs to understand the behavior lf physical structures under load. An ability to intuit or “feel” structural behavior is possessed by those having much experience involving structural analysis, both qualitative and quantitative. The consequent knowledge of how forces, stresses, and deformations build up in different materials and shapes is vital to the development of this “sense”.
Structural analysis is the process of determining the forces and deformations in structures due to specified loads so that the structure can be designed rationally, and so that the state of safety of existing structures can be checked.
In the design of structures, it is necessary to start with a concept leading to a configuration which can then be analyzed. This is done so members can be sized and the needed reinforcing determined, in order to: a) carry the design loads without distress or excessive deformations (serviceability or working conditions); and b)to prevent collapse before a specified overload has been placed on the structure(safety or ultimate condition).
Since normally elastic conditions will prevailly undue working loads, a structural theory based on the assumptions of elastic behavior is appropriate for determining serviceability conditions. Collapse of a structure will usually occur only long after the elastic range of the materials has been exceeded at critical points, so that an ultimate strength theory based on the inelastic behavior of the materials is necessary for a rational determination of the safety of a structure against collapse. Nevertheless, an elastic theory can be used to determine a safe approximation to the strength of ductile structures (the lower bound approach of plasticity), and this approach is customarily followed in reinforced concrete practice. For this reason only the elastic theory of structures is pursued in this chapter.
Looked at critically, all structures are assemblies of three-dimensional elements,
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河南理工大学本科毕业设计 中文翻译
the exact analysis of which is a forbidding task even under ideal conditions and impossible to contemplate under conditions of professional practice. For this reason, an important part of the analyst’s work is the simplification of the actual structure and loading conditions to a model which is susceptible to rational analysis.
Thus, a structural framing system is decomposed into a slab and floor beams which in turn frame into girders carried by columns which transmit the loads to the foundations. Since traditional structural analysis has been unable to cope with the action of the slab, this has often been idealized into a system of strips acting as beams. Aldo, long-hand method has been unable to cope with three-dimensional framing systems, so that the entire structure has been modeled by a system of planar subassemblies, to be analyzed one at a time. The modern matrix-computer methods have revolutionized structural analysis by making it possible to analyze entire systems, thus leading to more reliable predictions about the behavior of structures under loads.
Actual loading conditions are also both difficult to determine and to express realistically, and must be simplified for purposes of analysis. Thus, traffic loads on a bridge structure, which is essentially both of dynamic and random nature, is usually idealized into statically moving standard trucks, or distributed loads, intended to simulate the most severe loading conditions occurring in practice.
The most important use of structural analysis is as a tool in structural design. As such, it will usually be a part of a trial-and error procedure, in which an assumed configuration with assumed dead loads is analyzed, and the members designed in accordance with the results of the analysis. This phase is called the preliminary designed; since this design is still subject to change, usually a crude, fast analysis method is adequate. At this stage, the cost of the structure is estimated, loads and member properties are revised, and the design is checked for possible improvements. The changes are now incorporated in the structure, a more refined analysis is performed, and the member design is revised. This project is carried to convergence,
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河南理工大学本科毕业设计 中文翻译
the rapidity of which will depend on the capability of the designer. It is clear that a variety of analysis methods, ranging from” quick and dirty to exact”, is needed for design purposes.
An efficient analyst must thus be in command of the rigorous methods of analysis, must be aware of available design and analysis aids, as well as simplifications permitted by applicable building codes. An up-to-date analyst must likewise be versed in the bases of matrix structural analysis and its use in digital computers as well as in the use of available analysis programs or software
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河南理工大学本科毕业设计 中文翻译
高层建筑展望及建筑结构
区域规划对高层建筑物的密度和对自然采光设计可能引起道德问题将产生影响。能源的有限性将继续成为建筑设计面临的独特挑战。新老建筑的结合将会给我们的城市带来人情味。要设计建造出经济实用，以人为本的建筑物，将会是业主和概念设计师在20世纪80年代面临的挑战。
1980年欲斯柯摩尔、奥英斯和米瑞尔（SOM）设计的莱弗公寓获得了美国建筑师协会授予的25年奖“以奖励具有深远意义的优秀建筑设计”。这响奖每年授予一座房龄在25~35年之间的建筑物。用刘易斯.芒福德的话来说莱弗公寓是“第一座集现代材料、现代施工、现代功能与现代设计方案为一体的办公楼”。在当时，这样大胆的构思只有像设计师戈登.邦沙福特和业主—莱弗兄弟公司当时的总裁查尔斯.卢克曼那样富于幻想的人才能创造出来了。而且，这项工程包含了几个”第一”：（1）它是第一座全封闭的玻璃大厦；（2）它是SOM三人合作设计的第一栋办公楼；（3）它是公园大街第一座一层楼不设零售商场的办公楼。今天，经过众多外观相似而柱网变化的设计，我们已难以对建筑物进行归类，这也许是高层建筑设计的缩影。除了最近竣工的几栋低层楼房似乎比较怡人外，在我们的许多城市中，多数高层建筑物看上去就像图表上的柱标，好似一块块单调而又笨拙的巨石。难道这就是高层建筑设计行业的终点吗？也许不是。有迹象表明其发展是非常令人鼓舞的。建筑师和业主最近已开始公开讨论设计问题。也许我们正处在一个新时代的开端，20世纪80年代也许会产生一些像邦沙福特和卢克曼那样的幻想家。要是如此，他们会面临什么样的限制或挑战呢？ 区域规划 很显然，城市可以限制高层建筑的密度，也就是减少每平方英里高层建筑的数量。1980年，“堵塞网”这个术语第一次在纽约市公开使用。它的出
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河南理工大学本科毕业设计 中文翻译
现在公众心中引起恐慌。这个词指的是城市中四面八方的街区同时出现的交通停滞不动的现象，堵塞甚至一直延伸到隧道里和高架桥上。奇怪的是，这种事情竟然发生在纽约燃料短缺、油价高涨的年份。很显然，要想避免类似情况的出现，就必须大幅度地降低人口、降低活动场所油价车辆的密度。区域规划也许是唯一长远的解决方法。
城市居民由于收到高层建筑的遮挡而见不到阳光，因此，阳光规划将越来越受欢迎。无论高层建筑设计得如何节能，它同时有可能剥夺居住者和邻居享受阳光的权力。20世纪80年代享受阳光的权力会成为一个十分有趣的道德问题，这个问题会彻底改变城市的建筑布局。混合用途的分区规划在20世纪70年代还只是一种在经济上可行的抉择，在20世纪80年代将会得到普及，特别是将混合功能分区规划与阳光分区规划相结合，让所有的住户都享受到阳光。 整修改造 伊莫利.罗斯和桑斯两人合作设计的纽约王宫酒店是对麦迪逊大街上翻修后的古建筑维拉德公寓的补充和增色。这是一个如何对待可抢救的古建筑精品的突出实例。20世纪80年代对中西建筑物的重复利用将是人情味和温馨回到建筑物的途径。无论出于什么原因，如果我们必须继续使用玻璃和铝材进行那种呆板的方式设计的话，我们会发现新老建筑的结合将成为未来富有人情味建筑设计的大趋势。
概念设计 有些建筑杂志认为位于旧金山的美洲银行办公大楼对于该城市来说规模过大，位于波士顿的约翰.汉考克中心不仅与该城市的规模不成比例，而且与其特点不符，对于世界各地主要高层建筑物的类似评论还有不少。这类评论提出了有关设计程序，和谁是重点项目设计的决策者，以及上世纪80年代的建筑设计应由谁来决策等基本问题。
未来的幻想家，即建筑师和业主会回到更富人情味的设计吗？
在今后的几年里社会学家和心理学家会发挥他们的重要作用使这些幻想家相信一种截然不同的、合乎人体尺寸的新型建筑设计早该付诸实践吗？如果这
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