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美国代写被抓-冶金业冶炼建筑钢材的发展

从本篇美国代写被抓-冶金业冶炼的建筑钢材的发展中可以看出,从十九世纪中叶开始,冶金业冶炼并轧制出抗拉和抗压强度都很高、延性好、质量均匀的建筑钢材,随后又生产出高强度钢丝、钢索 。于是适应发展需要的钢结构得到蓬勃发展。除应用原有的梁、拱结构外,新兴的桁架、框架、网架结构、悬索结构逐渐推广,出现了结构形式百花争艳的局面。建筑物跨径从砖结构、石结构、木结构的几米、几十米发展到钢结构的百米、几百米,直到现代的千米以上。于是在大江、海峡上架起大桥,在地面上建造起摩天大楼和高耸铁塔,甚至在地面下铺设铁路,创造出前所未有的奇迹。接下来有关美国代写被抓-冶金业冶炼建筑钢材的发展具体分析如下:

In order to adapt to the development of steel structure engineering, on the basis of Newtonian mechanics, material mechanics, structural mechanics, engineering structure design theory came into being. The theory of construction machinery, construction technology and construction organization design has also developed accordingly. Civil engineering has become a science from experience, with a new look in engineering practice and basic theory, thus contributing to the more rapid development of civil engineering.

Concrete came into being in the 1820s when Portland cement was made. Concrete aggregates can be locally sourced and concrete components are easy to form, but the tensile strength of concrete is very small and its use is limited. After the middle of the 19th century, the production of iron and steel surged, followed by the emergence of reinforced concrete, a new type of composite building material, in which the steel bears the tension and the concrete bears the pressure, giving full play to their respective advantages. Since the beginning of the 20th century, reinforced concrete has been widely used in various fields of civil engineering.

From the 1930s, prestressed concrete appeared. The crack resistance, stiffness and bearing capacity of prestressed concrete structure are much higher than that of reinforced concrete structure, so it is more widely used. Civil engineering has entered the historical period when reinforced concrete and prestressed concrete dominate. The appearance of concrete brings new economical and beautiful engineering structure form to the building, and makes the civil engineering produce new construction technology and engineering structure design theory. This is another leap in civil engineering.

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