首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
DEVELOPMENTS IN THE CONSTRUCTION OF TALL BUILDINGS 1 Until the nineteenth century, most tall buildings were constructed of loa
DEVELOPMENTS IN THE CONSTRUCTION OF TALL BUILDINGS 1 Until the nineteenth century, most tall buildings were constructed of loa
admin
2012-01-14
38
问题
DEVELOPMENTS IN THE CONSTRUCTION OF TALL BUILDINGS
1 Until the nineteenth century, most tall buildings were constructed of load-bearing masonry walls. Masonry walls had to be thick, particularly at the base, to support a building’s great weight. Stoneworkers built these walls by placing stone upon stone or brick upon brick, adding strength and stability by placing layers of mortar or cement between the stones. Floors and roofs had to be supported by wooden beams, but the major vertical
force
of buildings was supported by thick masonry walls. This imposed serious limitations on the number and size of windows.
2 In the 1850s, an alternative was emerging that would eliminate the need for exterior weight-bearing walls: a three-dimensional grid of metal beams and columns. The introduction of metal construction made it possible to build larger interior spaces with fewer columns than before. The new construction was capable of supporting all the loads to which a building might be subjected, including the vertical forces caused by the weight of the floors and the horizontal forces caused by the wind or earthquakes.
3 The first buildings to depart from the load-bearing wall tradition were iron-framed. Wrought iron, shaped by hammering the heated metal or roiling it under extreme pressure, contains almost no carbon, and when used as floor beams, it can support a great deal of weight. An interior wrought iron skeleton supported all of the hnilding’s weight. Exterior walls of reinforced concrete acted mainly as weatherproofing.
As masonry yielded to concrete, walls that once bore weight evolved into thin curtain walls that would allow more windows.
These modifications produced sturdier, lighter, and taller buildings that quickly became known as skyscrapers. Skyscrapers satisfied the growing need for office space, warehouses, and department stores. Buildings of eight or more stories quickly transformed the city skyline and dominated the central business districts of American cities such as New York, Chicago, and St. Louis.
4 Skyscrapers differed from previous tall structures with their use of technical innovations such as cast iron and the elevator. The development of cast iron technology, in which molten iron is poured into a mold, made modern plumbing possible. Cast iron pipes, fittings, and valves could deliver pressurized water to the many floors of tall buildings and drain wastewater out. The invention of the mechanical elevator made it possible to construct even taller buildings. Before the elevator, office buildings were rarely more than four or five stories high. In 1857, the first passenger elevator equipped with safety brakes prevented the elevator from falling to the basement when a cable broke. The elevator made the upper floors as
rentable
as the first floor, liberating architecture from dependence on stairways and human muscle.
5 Not only did these innovations have important uses in the engineering of tall buildings, but
they
also erased the traditional architectural distinctions separating the bottom, middle, and top of a building. Architects designed towers that reached to the heavens in a continuous vertical grid. Iron construction established the principle of repetitive rhythms as a natural expression of construction, as well as the idea that buildings could be made of new materials on a vast scale.
6 Construction techniques were
refined
and extended over the next several decades to produce what architectural historians have called "true skyscrapers," buildings over twenty stories high. The invention of steel was particularly significanti as steel T-beams and I-beams replaced iron in these new structures. Steel weighs less than half as much as masonry and exceeds both masonry and iron in tension and compression strength as well as resistance to fatigue. Steel rivets replaced iron bolts and were in turn replaced by electric arc welding in the 1920s. The skyscraper’s steel skeleton could meet all of the structural requirements while occupying very little interior space. Exterior curtain walls could be quite thin, since their only function now was to let in light and keep the weather out.
The word refined in paragraph 6 is closest in meaning to
选项
A、reviewed
B、copied
C、made cheaper
D、improved
答案
D
解析
Refined means improved in this context. Clues: Construction techniques were refined and extended.., to produce... "true skyscrapers," buildings over twenty stories high. The paragraph describes improvements in materials and techniques that enabled buildings to be taller than ever before. (1.4)
转载请注明原文地址:https://kaotiyun.com/show/SwyO777K
0
托福(TOEFL)
相关试题推荐
Questions7-10Labelthediagrambelow.ChooseNOMORETHANONEWORDfromthepassageforeachanswer.Writeyouranswersinbox
TheHistoryoftheGuitarTheword’guitar’wasbroughtintoEnglishasanadaptationoftheSpanishword’guitarra,’whichwas,
Choosethecorrectletter,A,B,CorD.Writethecorrectletterinboxesonyouranswersheet.InEurope,aresearchhintsth
DothefollowingstatementsagreewiththeinformationgiveninReadingPassage?Inboxes11-13onyouranswersheet,writeTRU
LookatthefollowingstatementsandthelistofOlympictorchesbelow.MatcheachstatementwiththecorrectOlympictorch,
AccordingtoMrSingh,onwhichthingdomanypeoplemakesuperficialobservations?MrSinghbelievesthatWesternmethodsplus
【21】Whatdoesthetutorgivethestudentalistof?
Whatpercentageofthestudentsaremature?Theuniversityaccommodationserviceshavea______thatstudentscanlookthrough
Thingsthatseemexcitingandfascinatingcanlaterseem______accordingtoAliandJatinder.Katarinadecidestoregisterat
AYourpassport.BYourchildren’spassports.CYourPoliceRegistrationCertificate.DAletterfromyourcollege
随机试题
影响蛛网膜下腔阻滞麻醉平面的因素包括
A.Coombs试验B.Ham试验C.红细胞渗透性脆性D.免疫球蛋白电泳E.冷溶血试验诊断温抗体型自身免疫性溶血性贫血的重要实验室检查是
A.泡腾片剂B.舌下片C.激素类气雾剂D.缓控释制剂E.透皮贴剂宜整片或整丸吞服,严禁嚼碎和研碎服用的剂型是
根据《物权法》的规定,下列各项中,只能专属于国家所有的有:()
隧道施工监控量测的必测项目不包含拱脚下沉监测。()
桥梁拆除工程必须由具备()专业承包资质的单位施工,严禁将工程非法转包。
亚洲R国H公司推出了一个名为“东大机器人”的项目,该项目的目标是通过R国顶级学府J大学的入学考试。2013年以来,“东大机器人”每年都参加J大学的入学考试,但连续3年的得分均低于J大学的录取分数线。H公司于2016年11月正式宣布因项目过于复杂而最终放弃该
凡是知道案件情况的人,都应当作证。()
海上发生了两船相碰事件,海事部门已经就此次事故做了责任划分,但是有一方对结果表示不满,认为自己不应该承担责任。于是纠集了一群船员及家属到海事局办事大厅闹,声称不给解决就跳海。你怎么解决?
要素教育论
最新回复
(
0
)