1、本科毕业设计（论文）外文翻译题 目 高层建筑结构探索住宅 3学 院 建工学院 专 业 土木工程班 级 09 土木本一 学 号 0935学生姓名 指导教师 温州大学教务处制外文资料来源及题目Building Materials Selection and SpecificationFaeq A .A. Radwan，sep.2010，第 4卷，第 9号（串行 34号）杂志，ISSN1934.7359，美国土木工程及建筑协会 .译成中文后题目建筑材料的选择和规格指导教师审阅意见：签名：年 月 日外文原文Building Materials Selection and SpecificationFa
2、eq A. A. RadwanFaculty of Engineering, Near East University, KKTC, Lefkosa, Mersin 10, TurkeyAbstract:The limitations in the selection of the building materials and to the sustainability of any building construction materials that can be used are presented. The practices and techniques that can be u
3、sed in reducing and minimizing the environmental impacts of building are discussed. Recommendations of using secondary and recycled materials in the construction of buildings are given. Framework for methods of assessment of the sustainability in building construction for environmental performance i
4、s presented. Key Words:Limitations, sustainability, environmental impacts, framework, climate.1.IntroductionThere is an apparently unbounded range of possibilities for the selection of building materials for the construction of structures of almost any shape or stature. Its quality will affect the s
5、tructure function and long life, and requirements may differ with climate, soil, site size, and with the experience and knowledge of the designer. The factors that have the most outstanding solutions are impermeability, control of heat, air, and water flow, and the stability of the structure 1-3. Ra
6、w materials extraction, manufacturing processes, and the transportation of the materials to the project site have a multitude of impacts on the environment. These include the disruption of habitats and ecological systems, use of water, and, through energy use, the emissions of air pollutants and cli
7、mate change gases. Building materials also have major impacts on the building occupants manufacture, construction of buildings and the use of building materials make a significant environmental impact internally, locally and globally. But it is not easy to deliver information to make adequate inclus
8、ion decisions considering the whole life cycle of a building. Decisions on sustainable building integrate a number of strategies during the design, construction and operation of building projects. Selection of sustainable building materials represents an important strategy in the design of a buildin
9、g.2. SustainabilityIn recent years, the concept of sustainability has been the subject of much disputation by academics and professionals alike. In 1987, the World Conference on Environment and Development defined sustainable development as development that meets the needs of the present without com
10、promising the ability of future generations to meet their own needs (WCED, 1987).Sustainability must address ecological impacts, regardless of conflicting interpretations of the WCED definition. A good sustainable product must give as much satisfaction as possible for the user. If not, it will be un
11、successful on the market and an economic failure. It is also important to inform people as to what basis a certain product is considered to be sustainable or not and why they should buy it 4- 5. When developing a new product, it is illustrative to move between the three corners Ecology, Equity and E
12、conomy in order to obtain a suitable balance so that each category can be fulfilled in the best way. Ecology (environmental protection). Equity (social equity). Economy (economic growth). 2.1 Materials Selection and SustainabilityAmong the notable technological developments of the 20th century has b
13、een the development of tens of thousands of new materials for use in construction and engineering. The construction industry has also grown to the point where it is a very large consumer of energy and materials. Concern for the environment and the impact of human activity on the Earths ecological sy
14、stems has now become clear sighted. We are faced with the problems of material selection and the environmental consequences of their use. Environmentalists have proposed various methods for assessing the impact of materials and energy use, these include ecological foot printing, ecological rucksacks
15、, embodied energy and carbon dioxide values, and so on. Engineers have put forward rational selection methods for the choice of materials. These techniques will be reviewed and explored in an attempt to provide an environmentally-aware, materials selection method- logy for use in construction. Stric
16、tly, the term sustainable means that something is capable of being sustained not for an hour, or a day, or a week, month or year, but indefinitely. The implication is that if some process which uses materials and energy is described as sustainable, then the materials and energy which are consumed ar
17、e capable of being replaced by natural or other processes as fast as they are consumed. In many cases materials and energy appear to be consumed at a faster rate than they are being replaced. However, to make a judgment, we would need to know what the respective supply and consumption rates are in o
18、ther words we need some quantitative or numerical index to help us 2.2.2 Environmental CriteriaSince construction uses such large quantities of materials, it has a major impact on the environment. In order to assess and evaluate such impact, a number of criteria or indices have been devised by econo
19、mists, engineers and environmentalists, and the more important of these are the following 2. 2.2.1 Embodied EnergyThis is quite simply the amount of energy consumed in manufacturing a unit quantity of a material, and it is usually expressed in kJ/kg. Its value is determined by the efficiency of the
20、manufacturing plant. Values range from 275 GJ/tonne for aluminum (a high value) to 0.1 GJ/tonne for gravel aggregates (a low value) 2. 2.2.2 Embodied Carbon DioxideEmbodied C02 is similar to embodied energy. It is the weight of C02 emitted during manufacture of unit weight of the material, and is us
21、ually expressed as kg of C02 per ton.Again, the value will depend upon the efficiency of the manufacturing plant 2. 2.2.3 Ecological RucksackThe ecological rucksack concept was devised as a way of assessing material efficiency by F. Schmidt 一 Bleek 6. He recognized that many tonnes of raw material c
22、ould be extracted and processed to make just one kilogram of material. For example, the environmental rucksack for the precious metal platinum is 250,000:1. 2.3 Rational Selection MethodThere are various approaches to the problem of selecting materials from the huge numbers now available. Designers
23、can have recourse to materials property charts and data books. Alternatively, they can talk to their colleagues, hoping that by widening the knowledge circle, they will not omit a significant group of materials. Another strategy is simply to specify the same or a similar material to those used in pr
24、evious, similar designs. All these are valid approaches, but they may result in the specification of a less than ideal material and overall, a less than optimal solution to the problem 3-5.The basis of the rational selection methods devised to date is a recognition that the performance of a componen
25、t, artifact or structure is limited by the properties of the materials from which it is made. It will be rare for the performance of the item to depend solely on one material property; in nearly all cases, it is a combination of properties, which is important. To give an example, in lightweight desi
26、gn, strength to weight ratio of, and stiffness to weight ratio E/pwill be important. Ref. 3 has put forward the idea of plotting material properties against each other to produce material property maps. On these maps, each class of material occupies a field in material property space, and sub-fields
27、 map the space occupied by individual materials. These materials property charts are very information-rich they carry a large amount of information in a compact but accessible form. Interestingly, they reveal correlations between material properties, which can help in checking and estimating data, a
28、nd they can also be used in performance optimization, in a manner such as that set out as follow. If we consider the complete range of materials, it immediately becomes apparent that for each property of an engineering material there is a characteristic range of values, and this range can be very la
29、rge. For example, consider stiffness (Youngs Modulus E). Materials range from jelly (very low stiffness) up to diamond (very high stiffness). The properties can span five decades (orders of magnitude), A number of conclusions can be drawn, including: (1) A rational selection method such the one put
30、forward by Ashby is capable of incorporating environmental parameters such as embodied energy and C02 or the environmental rucksack concepts, thereby making possible rational selections based on environmental considerations. (2) This method is not as simple to use as the environmental preference met
31、hod or the environmental profiles method. However, this rational method could be used to generate data for the environmental profiles and preference methods. (3) The construction industry needs to take steps to better integrate itself into the materials cycle. The quantity of demolition waste needs
32、to be reduced, and more of it should be recycled. To this end, the building designers need to keep full records of materials of construction, and buildings need to be designed for easy dismantling at the end of their useful lives. 3. Foundations and Construction Component In any consideration of whi
33、ch building materials and alternatives can feasibly be integrated into the foundations of a large-scale development there are several limitations that must be considered. In terms of the actual materials that may be used, there are three main limitations. First, because of the large scale and heavy
34、loads that the foundations must support, strength is imperative. Any materials must be consistently strong and able to effectively distribute the weight of the structure. The second major limitation is climate. In areas with sub-zero winter conditions, frost heave is a major consideration. For this
35、reason, foundations must be deep enough to support the structure despite any changes in near-surface volume; shallow foundations will be insufficient unless certain innovative steps are taken. The limitation of climate also influences any decision on insulating foundations. Finally, there is the con
36、sideration of cost. This consideration is reliant on material availability, cost per unit, and building techniques and associated labor. For these reasons, the only materials that can feasibly be used are concrete and steel. Therefore, the alternatives for minimizing impact lie more in the methods o
37、f construction and any realistic structural changes that can be made. The three main foundation components of concrete, steel, and insulation will be examined as the only reasonable materials for the construction of a building with limitations such as the foundations 1. 3.1 ConcreteIt is the fundame
38、ntal component of the foundation construction, receiving the building loads through walls or posts and distributes them down and outwards through the footings. Concrete and cement have ecological advantages which include durability, long life, heat storage capability, and (in general) chemical inert
39、ness 8. The life cycle concerns of concrete are as follows. First, there is land and habitat loss from mining activities. Furthermore, the quality of both air and water quality suffer from the acquisition, transportation, and manufacture. Carbon dioxide emissions are also a negative environmental im
40、pact accrued through the production and use of concrete. Similarly, dust and particulate are emitted at most stages of the concrete life-cycle. $oth carbon dioxide and particulate matter have negative impacts on air quality 1. Water pollution is also another concern associated with the production of
41、 concrete at the production phase. Fly ash is by-product of the energy production from coal-fired plants and increasing its proportion in cement is environmentally beneficial in two ways. First, it helps in reducing the amount of solid waste which requires disposal. As well, fly ash in the cement mi
42、xture reduced the overall energy use by changing the consistency of the concrete. Fly ash, increases concrete strength, improves sulfate foundation, decreases permeability, reduced the water ratio required, and improves the pump ability and workability of the concrete 9. Now in the United States, th
43、e Environmental Protection Agency requires that all buildings that receive federa funding contain fly ash and most concrete producer: have access to this industrial waste 9. There are alternative methods of both making concrete and building foundations with this concrete that have environmental bene
44、fits, no matter the structure scale or climate. These include Autoclaved Aerated Concrete, the increased integration of fly ash into the cement mixture, and the use of pre-cast foundation systems to reduce resource use. Through consideration and possible integration of these alternatives, impacts co
45、uld potentially be reduced. 3.2 SteelAs wood resources are becoming limited, steel is increasingly popular with builders. In the case of a large-scale building, steel reinforcement is basically a necessity for overall strength and weight distribution. The initial life cycle impacts of steel use are
46、similar to those of concrete. These include land and habitat loss from mining activities, and air and water quality degradation from materials acquisition and manufacture 1. However, the largest proportion of steel used nowadays contains a percentage of recycled materials. In terms of improving envi
47、ronmental conditions by reducing impacts, this is the only real recommendation for the use of steel in building foundations; to purchase recycled steel products. Not only would this reduce industrial and commercial solid waste, such a decision would also reward the manufacturers of such products. 3.
48、 3 InsulationNew and innovative pre-cast building foundations are becoming increasingly available and feasible for implementation. These new systems can reduce the overall raw material use, as well as conserve energy through the creation of an efficient building envelope. A further used of this rigi
49、d insulation as a skirt around the building foundations helps to eliminate any potential frost problems, improve drainage, and help further reduce heat loss. A polyethylene air and water vapor barrier is applied above the insulating layer, as is a three to four inch layer of sand. These shallow foundation systems have excellent insulating properties, decreased use of raw materials for concrete, and comparatively low demands for labor. However, the use of rigid insulation is increased. Also, in soils where frost and drainage is a c
