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
考研
Highways Early in the 20th century, most of the streets and roads in the U. S. were made of dirt, brick, and cedar wood block
Highways Early in the 20th century, most of the streets and roads in the U. S. were made of dirt, brick, and cedar wood block
admin
2010-06-10
40
问题
Highways
Early in the 20th century, most of the streets and roads in the U. S. were made of dirt, brick, and cedar wood blocks. Built for horse, carriage, and foot traffic, they were usually poorly cared for and too narrow to accomrrmdate(容纳) automobiles.
With the increase in auto production, private turnpike (收费公路) companies under local authorities began to spring up, and by 1921 there were 387, 000 miles of paved roads. Many were built using specifications of 19th century Scottish engineers Thomas Telford and John MacAdam (for whom the macadam surface is named ), whose specifications stressed the importance of adequate drainage. Beyond that, there were no national standards for size, weight restrictions, or commercial signs. During World War I , roads throughout the country were nearly destroyed by the weight of trucks. When General Eisenhower returned from Germany in 1919, after serving in the U.S. Amy’s first transcontinental motor convoy(车队) , he noted: "The old convoy had started me thinking about good, two-lane highways, but Germany’s Autobahn or motorway had made me see the wisdom of broader ribbons across the land. "
It would take another war before the federal government would act on a national highway system. During World War Ⅱ, a tremendous increase in trucks and new roads were required. The war demonstrated how critical highways were to the defense effort. Thirteen percent of defense plants received all their supplies by truck, and almost all other plants shipped more than half of their products by vehicle. The war also revealed that local control of highways had led to a confusing variety of design standards. Even federal and state highways did not follow basic standards. Some states allowed trucks up to 36, 000 pounds, while others restricted anything over 7,000 pounds. A government study recommended a national highway system of 33,920 miles, and Congress soon passed the Federal-Aid Highway Act of 1944, which called for Strict, centrally controlled design criteria.
The interstate highway system was finally launched in 1956 and has been hailed as one of the greatest engineering public works projects of the century. To build its 44, 000-mile web of highways, bridges, and tunnels, hundreds of unique engineering designs and solutions had to be worked out. Consider the many geographic features of the country: mountains, steep grades, wetland, rivers, deserts and plains. Variables included the slope of the land, the ability of the pavement to support the load, the intensity of road use, and the nature ot"the underlying soil. Urban areas were another problem. Innovative designs of roadways, tunnels, bridges, overpasses, and interchanges that could run through or bypass urban areas soon began to weave their way across the country, forever altering the face of America.
Long-span, segmented-concrete, cable-stayed bridges such as Hale Boggs in Louisiana and the Sunshine Skyway in Florida, and remarkable tunnels like Fort McHenry in Maryland and Mt. Baker in Washington, met many of the nation’s physical challenges. Traffic control systems and methods of construction developed under the interstate program soon influenced highway construction around the world, and were invaluable in improving the condition of urban streets and traffic patterns.
Today the interstate system links every major city in the U. S. , and the U.S. with Canada and Mexico. Built with safety in mind, the highways have wide lanes and shoulders, dividing medians or barriers, long entry and exit lanes, curves engineered for safe turns, and limited access. The death rate on highways is half that of all other U. S. roads (0.86 deaths per 100 million passenger miles compared to 1.99 deaths per 100 million on all other roads).
By opening the North American continent, highways have enabled .consumer goods and services to reach people in remote and rural -areas of the country, spurred the growth of suburbs, and provided people with greater options in terms of jobs, access to cultural programs, health care, and other benefits. Above all, the interstate system provides individuals with what they cherish most:personal freedom of mobility.
The interstate system has been an essential element of the nation’s economic growth in terms of shipping and job creation:more than 75 percent of the nation’s freight deliveries arrive by truck; and most products that arrive by rail or air use interstates for the last leg of the journey by vehicle. Not only has the highway system affected the American economy by providing shipping routes, it has led to the growth of spin-off industries like service stations, motels, restaurants, and shopping centers. It has allowed the relocation of manufacturing plants and other industries from urban areas to rural.
By the end of the century there was an immense network of paved roads, residential streets, expressways, and freeways built to support millions of vehicles. The highway system was officially renamed for Eisenhower to honor his vision and leadership. The year constrution began he said: "Together, the united forces of our commuunication and transportation systems are dynamic elements in the very name we bear—United States. Without them, we would be a mere alliance of many separate parts. "
Many of the problems presented by the country’s geographical features found solutions in innovative engineering projects.
选项
A、Right
B、Wrong
答案
A
解析
(Lines 4-9,Para.4)Consider。the many geographic features of the country:mountains,steep grades,wetland,rivers,deseits and plains.Innovative designs 0f roadways,tunnels,bridges,overpasses,and interchanges that could run through or bypass urban areas soonbegan to weave their way across the country,forever altering the face of Amet4ca.由于特殊的地理环境,道路建设只能采取创新性的设计。
转载请注明原文地址:https://kaotiyun.com/show/9tsa777K
本试题收录于:
MBA联考(英语)题库专业硕士分类
0
MBA联考(英语)
专业硕士
相关试题推荐
Priortothe20thcentury,manylanguageswithsmallnumbersofspeakerssurvivedforcenturies.Theincreasinglyinterconnected
Eachyear,hundredsofthousandsofpeoplediefromheartattack,aleadingcauseofdeath.IntheLandmarkPhysicians’HealthS
TheChinaboomisbynowawell-documentedphenomenon.Whohasn’t【1】theMiddleKingdom’sastoundingeconomicgrowth(8percenta
TheChinaboomisbynowawell-documentedphenomenon.Whohasn’t【1】theMiddleKingdom’sastoundingeconomicgrowth(8percenta
Manynovelsthatattempttomirrortheworldarereally______oftherealitythattheyrepresent.
Everyoneshouldbe______toadecentstandardoflivingandanopportunitytobeeducated.
Thephrase"keeppeopleonedge"(Paragraph1)probablymeansto______.Whichofthefollowingistrueaboutthepresentecono
Oneofthemosteminentofpsychologists,ClarkHull,claimedthattheessenceofreasoningliesintheputtingtogetheroftwo
Oneofthemosteminentofpsychologists,ClarkHull,claimedthattheessenceofreasoningliesintheputtingtogetheroftwo
HighwaysEarlyinthe20thcentury,mostofthestreetsandroadsintheU.S.weremadeofdirt,brick,andcedarwoodblock
随机试题
简述党的先进性同党的纯洁性的相互关系。
富马酸酮替芬属于
急性心肌梗死患者出现阵发性室性心动过速,预示即将发生
资产类账户的借方一般登记()。
基金的估值主要是在基金存续期间从整个基金的层面对基金资产和负债进行()确定的过程。
早期人类的骸骨清楚:地显示他们比现代人更少有牙齿方面的问题。因此,早期人类的饮食很可能与今天的非常不同。以下哪项陈述最能强化上述论证?
软件开发模型用于指导软件开发。演化模型是在快速开发一个(28)的基础上,逐步演化成最终的软件。螺旋模型综合了(29)的优点,并增加了(30)。喷泉模型描述的是面向(31)的开发过程,反映了该开发过程的(32)特征。
Itwasasummerevening.Iwassittingbytheopenwindow,readinga【C1】______Suddenly,Iheardsomeonecrying,"Help!Help!"I
ManycountrieswillnotallowcigaretteadvertisingintheirnewspapersoronTVespeciallysincetheadvertisementsareusually
Hecouldrepairthecarhimselfbuthewouldratherhisson______it.
最新回复
(
0
)