【正文】 第一篇：土木工程專業(yè)英語(yǔ)論文翻譯建筑材料鋼的最嚴(yán)重缺點(diǎn)是它容易被氧化而需要被油漆或一些其他的適當(dāng)涂料保護(hù)。當(dāng)鋼被用于可能發(fā)生火災(zāi)環(huán)境時(shí), 鋼應(yīng)該包圍在一些耐火的材料中, 例如石料或混凝土。通常，鋼的組合結(jié)構(gòu)不易被壓碎除非是在冶金成分不好，低溫的不利組合, 或空間壓力存在的情況下。建筑用鋁仍然不廣泛被在土木工程結(jié)構(gòu)中用,雖然它的使用正在穩(wěn)定地增加。藉著鋁合金作為一個(gè)適當(dāng)?shù)倪x擇和對(duì)其進(jìn)行熱處理,可獲得各式各樣的強(qiáng)度特性。一些合金所展現(xiàn)的抗壓強(qiáng)度特性相似于鋼, 除線形彈性模量大約是7,000,000 牛/平方厘米，相當(dāng)于剛的三分之一。質(zhì)量輕和耐氧化是鋁的兩個(gè)主要優(yōu)點(diǎn)。因?yàn)樗奶匦詫?duì)熱處理是非常敏感的,當(dāng)鉚接或焊接鋁的時(shí)候，一定要小心仔細(xì)。一些技術(shù)已為制造預(yù)制鋁組合配件及形成若干的美麗的設(shè)計(jì)良好的外型結(jié)構(gòu)的鋁制結(jié)構(gòu)而發(fā)展起來(lái)。組合房屋配件制造的一般程序藉由螺栓連接，這似乎是利用建筑用鋁的最有前途的方法。加強(qiáng)和預(yù)應(yīng)力混凝土是主要的建筑材料。天然的水泥混凝土已經(jīng)被使用長(zhǎng)達(dá)數(shù)世紀(jì)之久?，F(xiàn)代的混凝土建筑興起于十九世紀(jì)中葉,盡管人造水泥被 Aspidin，, 但作為一種建筑材料它占統(tǒng)治地位是在二十世紀(jì)初期。后五十年鋼筋混凝土結(jié)構(gòu)設(shè)計(jì)和建筑得到迅速發(fā)展, 早期在法國(guó)的 Freyssinet 和比利時(shí)的 Magnel被大量使用。素混凝土作為建筑材料有一個(gè)非常嚴(yán)重的缺點(diǎn)：就是它的抗拉強(qiáng)度非常有限, 只是它的抗壓強(qiáng)度的十分之一。素混凝土不僅受拉破壞是脆性破壞，而且受壓破壞也是在沒有多大變形預(yù)兆的情況下發(fā)生的準(zhǔn)脆性破壞。(當(dāng)然,在鋼筋混凝土建筑中,可以得到適當(dāng)?shù)难有?。只有進(jìn)行適當(dāng)?shù)酿B(yǎng)護(hù)和合理的選擇并且摻加適當(dāng)?shù)幕旌咸旒觿?否則 霜凍破壞能嚴(yán)重的損害混凝土。在長(zhǎng)期荷載作用下混凝土在選擇設(shè)計(jì)受壓情況方面要仔細(xì)考慮。在硬化的時(shí)候和它的早期養(yǎng)護(hù)下,混凝土收縮占主要地位, 因此需要添加適當(dāng)?shù)乇壤奶砑觿┒矣眠m當(dāng)?shù)慕ㄖ夹g(shù)來(lái)控制。藉由所有的這些可能的嚴(yán)重缺點(diǎn)，工程師已經(jīng)試著為各種實(shí)際結(jié)構(gòu)設(shè)計(jì)建立美麗的，持久的，和經(jīng)濟(jì)的鋼筋混凝土結(jié)構(gòu)。這是藉著設(shè)計(jì)尺寸和鋼筋排列安排的謹(jǐn)慎選擇，和適當(dāng)?shù)乃嗟陌l(fā)展已經(jīng)趨于同步, 適當(dāng)添加劑混合比例, 混合配置, 而且養(yǎng)護(hù)技術(shù)和建筑方法，儀器的快速發(fā)展?；炷辆哂卸喾N用途，其組成材料廣泛可取，并且能非常方便地澆制成滿足強(qiáng)度及功能要求的形狀，同時(shí)，隨著新型預(yù)應(yīng)力混凝土、預(yù)制混凝土以及普通混凝土施工方法令人興奮的進(jìn)一步改善和發(fā)展的潛力，這些因素綜合起來(lái)使得混凝土在絕大多數(shù)結(jié)構(gòu)中有著比其他材料更大的競(jìng)爭(zhēng)力。在現(xiàn)代,藉由鋼和加強(qiáng)鋼筋的使用量在建筑結(jié)構(gòu)中的增加,木材在建筑期間主要地已經(jīng)被撤離到附屬的、暫時(shí)的和次要的結(jié)構(gòu)中使用,成為建筑材料的次要成員。然而, 現(xiàn)代的技術(shù)在最后六十年中已經(jīng)有使木材作為建筑材料恢復(fù)生氣的跡象,藉由大量的改良了木材的加工方法,各種不同的處理方法增加了木材的耐久性, 而且疊片木材連同使用黏結(jié)技術(shù)的革命使得木材的性能有了更好的保證。各向同性的膠合板是最廣泛使用的壓層膠合板，隨著技術(shù)的發(fā)展，壓層膠合板已經(jīng)發(fā)展成為特定的結(jié)構(gòu)材料并對(duì)混凝土和鋼造成了強(qiáng)大的競(jìng)爭(zhēng)力。將來(lái)可能發(fā)展的材料是工程塑料和稀有金屬及他們的合金,如鈹，鎢，鉭，鈦，鉬，鉻，釩和鈮。有許多不同的塑料可以用，而且這些材料所展現(xiàn)的力學(xué)性能在很大的范圍內(nèi)改變。在如此許多的特性中我比較設(shè)計(jì)方案選擇適當(dāng)?shù)目赡艿乃芰喜牧鲜强赡艿摹?duì)塑料的使用受經(jīng)驗(yàn)的限制。一般而言，塑料一定要與空氣隔離。設(shè)計(jì)的這一個(gè)方面要求主要是對(duì)塑料結(jié)構(gòu)元素在使用中的考慮。塑料被應(yīng)用的最有希望的潛能之一是嵌板和貝殼型結(jié)構(gòu)。疊片或夾心嵌板已經(jīng)被用于此種結(jié)構(gòu)以鼓勵(lì)未來(lái)建筑大量應(yīng)用這一個(gè)類型材料。另一種引起注意的材料由纖維或像粒子的膠結(jié)加筋的微粒組成的合成物材料正在開發(fā)。雖然一種由玻璃或塑料膠結(jié)材料組成的玻璃纖維加筋合成物已經(jīng)被用長(zhǎng)達(dá)數(shù)年之久, 但是他們很可能退落為次要的結(jié)構(gòu)材料。加筋混凝土是另一個(gè)積極地被學(xué)習(xí)而且發(fā)展的混合料。一些實(shí)驗(yàn)正在工作情況下進(jìn)行。實(shí)驗(yàn)主要內(nèi)容為鋼和玻璃纖維，但是大部份的使用經(jīng)驗(yàn)在鋼纖維方面比較先進(jìn)。`Building materials The most serious disadvantage of steel is that it oxidizes easily and must be protected by paint or some other suitable steel is used in an enclosure where a fire could occur, the steel members must be encased in a suitable fireresistant enclosure such as masonry, , steel members will not fail in a brittle manner unless an unfortunate bination of metallurgical position, low temperature, and bior triaxial stress aluminum is still not widely used in civil engineering structures, though its use is steadily a proper selection of the aluminum alloy and its heat treatment, a wide variety of strength characteristics may be of the alloys exhibit stressstrain characteristics similar those of structural steel, except that the modulus of elasticity for the initial linearly elastic portion is about 10,000,000 psi(700,000 kgf/cm*cm)or about onethird that of and resistance to oxidation are, of course, two of the major advantages of its properties are very sensitive to its heat treatment, care must be used when riveting or welding techniques have been developed for prefabricating aluminum subassemblies that can be readily erected and bolted together in the field to form a number of beautiful and welldesigned shell general procedure of prefabrication and held assembly by bolting seems to be the most promising way of utilizing structural and prestesses concrete share with structural cement concretes have been used for concrete construction dates from the middle of the nineteenth century, though artificial Portland cement was patented by Aspidin, an Englishman, about several builders and engineers experimented with the use of steelreinforced concrete in the last half of the nineteenth century, its dominant use as a building material dates from the early decades of the twentieth last fifty years have seen the rapid and vigorous development of prestressed concrete design and construction, founded largely on early work by Freyssinet in France and Magnel in (unreinforced)concrete not only is a heterogeneous material but also has one very serious defect as a structural material, namely, its very limited tensile strength, which is only of the order of onetenth its pressive only is tensile failure in concrete of a brittle type, but likewise pression failure occurs in a relatively brittle fashion without being preceded by the forewarning of large deformations.(Of course, in reinforcedconcrete construction, ductile behavior can be obtained by proper selection and arrangement of the reinforcement.)Unless proper care is used in the selection of aggregates and in the mixing and placing of concrete, frost action can cause serious damage to concrete creeps under longterm loading to a degree that must be considered carefully in selecting the design stress the curing process and its early life, concrete shrinks a significant amount, which to a degree can be controlled by properly proportioning the mix and utilizing suitable construction all these potentially serious disadvantages, engineers have learned to design and build beautiful, durable, and economical reinforcedconcrete structures for practically all kinds of structural has been acplished by careful selection of the design dimensions and the arrangement of the steel reinforcement, development of proper cements, selection of proper aggregates and mix proportions, careful control of mixing, placing, and curing techniques and imaginative development of construction methods, equipment and versatility of concrete, the wide availability of its ponent materials, the unique ease of shaping its form to meet strength and functional requirements, together with the exciting potential of further improvements and development of not only the newer prestressed and precast concrete` construction but also the conventional reinforced concrete construction, bine to make concrete a strong petitor of other materials in a very large fraction of modern times, with the increased use of steel and reinforcedconcrete construction, wood has been relegated largely to accessory use during construction, to use in temporary and secondary structures, and to use for secondary members of permanent technology in the last sixty years has revitalized wood as a st