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
When an eight-lane steel-truss-arch bridge across the Mississippi River in Minneapolis collapsed during the evening rush hour on
When an eight-lane steel-truss-arch bridge across the Mississippi River in Minneapolis collapsed during the evening rush hour on
admin
2017-06-11
58
问题
When an eight-lane steel-truss-arch bridge across the Mississippi River in Minneapolis collapsed during the evening rush hour on August 1st 2007, 13 people were killed and 145 were injured. There had been no warning. The bridge was 40 years old but had a life expectancy of 50 years. The central span suddenly gave way after the gusset plates that connected the steel beams buckled and fractured, dropping the bridge into the river.
【R6】______The St Anthony Falls bridge, which opened on September 18th 2008 and replaces the collapsed structure, should do just that. It has an embedded early-warning system made of hundreds of sensors. They include wire and fibre-optic strain and displacement gauges, accelerometers, potentiometers and corrosion sensors that have been built into the span to monitor it for structural weaknesses, such as corroded concrete and overly strained joints.
【R7】______Another example is the six-lane Charilaos Trikoupis bridge in Greece, which spans the Gulf of Corinth, linking the town of Rio on the Peloponnese peninsula to Antirrio on the mainland. This 3km-long bridge, which was opened in 2004, has roughly 300 sensors that alert its operators if an earthquake or high winds warrant it being shut to traffic, as well as monitoring its overall health. These sensors have already detected some abnormal vibrations in the cables holding the bridge.【R8】______
The next generation of sensors to monitor bridge health will be even more sophisticated. For one thing, they will be wireless, which will make installing them a lot cheaper.【R9】______
Dr Lynch is the chief researcher on a project intended to help design the next generation of monitoring systems for bridges. He and his colleagues are also looking at how to make a cement-based sensing skin that can detect excessive strain in bridges. Individual sensors, says Dr Lynch, are not ideal because the initial cracks in a bridge may not occur at the point the sensor is placed.【R10】______He is also exploring a paint-like substance made of carbon nanotubes that can be painted onto bridges to detect corrosion and cracks. Since carbon nanotubes conduct electricity, sending a current through the paint would help engineers to detect structural weakness through changes in the paint’s electrical properties.
A. The new Minneapolis bridge joins a handful of "smart" bridges that have built-in sensors to monitor their health.
B. The kilometers of wire needed to connect sensors to central computers can add significantly to the system’s cost, according to Jerome Lynch of the University of Michigan, Ann Arbor.
C. By 2025 all bridges in American will have been equipped with this advanced technology.
D. A continuous skin would solve this problem.
E. In the wake of the catastrophe, there were calls to harness technology to avoid similar mishaps.
F. Engineers then installed additional weights as dampeners.
【R7】
选项
答案
A
解析
第二段提到Charilaos Trikoupis bridge的内容,由此可知A是正确答案。
转载请注明原文地址:https://kaotiyun.com/show/d5FO777K
0
考博英语
相关试题推荐
SallyKemmererhas,sofar,escapedNorthernCalifornia’srollingblackouts.ButupontheroofforherOaklandhome,workersa
Byfarthemostcommondifficultyinstudyissimplefailuretogetdowntoregularconcentratedwork.Thisdifficultyismuchg
Itisourfirm_____thatastepforwardhasbeentakenandwillbringthecountrybacktoeconomicprosperity.
Competitorsfrommorethanahundredcountrieshave_____inLosAngelesfortheOlympicGames.
Soil____isanaturalprocess.Itbecomesaproblemwhenhumanactivitycausesittooccurmuchfasterthanundernaturalconditi
Oneofthemajordifferencesbetweenmanandhisclosestlivingrelativeis,ofcourse,thatthechimpanzeehasnotdevelopedthe
AftertheviolentearthquakethatshookLosAngelesin1994,earthquakescientistshadgoodnewstoreport;Thedamageanddeath
Thegovernmentistryingtodosomethingto_____betterunderstandingbetweenthetwocountries.
Thecurrentpoliticaldebateoverfamilyvalues,personalresponsibility,andwelfaretakesforgrantedtheentrenchedAmerican
AstheyturnedintoUpshotRisewherehisparentslived,JackletgoofRuth’shand.UpshotRisewasnotahand-holdingstreet.W
随机试题
简述途径一目标理论的原理和指导原则。
属于传染源的是
谷胱甘肽的氨基酸组成是
采用双倍余额递减法计算折旧时,其正常折旧率是( )。
甲用人单位于2018年3月20日与劳动者乙签订一份期限为10个月的劳动合同。根据《劳动合同法》的规定,乙的试用期不得超过()个月。
基金产品线的深度是指一家基金管理公司所拥有的基金产品大类中具有多少更细化的子类基金。()
材料一:某地发生了一个灾难性突发事件,媒体采访当地一个领导干部,这位领导作了五分钟左右的回答。主要在讲当地领导是如何如何重视,措施是如何如何有力等。经媒体报道公布后,公众大为不满,说这位负责人只顾拍马屁,逢迎上意,报道不实。材料二:2005年11
阅读以下文字,回答问题。自然界纷呈多样的宏观物体还原到微观本源,它们都是由质子、中子和电子所组成的。这些粒子因而被称为“基本粒子”,意指它们是构造世上万物的基本砖块。事实上,基本粒子世界并没有这么简单。1932年由美国物理学家卡尔.安德逊在实验室
()是最能反映美国人的民族性格和精神倾向的影片类型。
在100BASE-TX的24口交换机中,若采用全双工通信,每个端口通信的数据速率最大可以达到()。
最新回复
(
0
)