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
33
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://jikaoti.com/ti/scmYFFFM
0
考博英语
相关试题推荐
Duringthepasttenorfifteenyears,agreatdealofattentionhasbeen【C1】______to"tellingitlikeitis,"or"lettingitallh
Insteadofbeingsituatedatafixedcampus,theCityUniversityconductsclassesatvarioussitesdeemedconvenienttostudents.
Thisisnottheright____toaskformyhelp;Iamfartoobusyeventolisten!
AstheyturnedintoUpshotRisewherehisparentslived,JackletgoofRuth’shand.UpshotRisewasnotahand-holdingstreet.W
Seariseasaconsequenceofglobalwarmingwouldimmediatelythreatenthatlargefractionoftheglobelivingatsealevel.Nea
Writeacompositionofabout200wordsonthefollowingtopic.RemembertowriteyourcompositiononAnswerSheetII.
ResalePriceMaintenanceisthenameusedwhenaretaileriscompelledtosellatapricefixedbythemanufacturerinsteadofc
Clonaid,acompanyassociatedbyagroupthatbelievesextraterrestrialscreatedmankind,announcedFridaythatithadproduced
IntheHanDynasty,theroyalgovernmentsentspecialenvoystothewesterncountriestodisseminatetheChineseculture.
In1784,fiveyearsbeforehebecamepresidentoftheUnitedStates,GeorgeWashington,52,wasnearlytoothless.Sohehireda
随机试题
某公司2014年的财务数据如下:假设企业的流动资产和流动负债均随销售收入的变化同比例变化。要求:如果留存收益比率为100%,销售净利率提高到6%,目标销售收入为4800万元,计算需要补充多少外部资金?
关于肺牵张反射的叙述,哪一项是正确的
Whendreaming,however,onetendstobelievefullyintherealityofthedreamworld,(howeverinconsistent,illogicalandoddi
A.不凝固血液B.粪臭味液体C.稀脓性、略带臭味液体D.血性液体E.血性液,胰淀粉酶含量高
聚合物薄膜控释系统中,包衣膜hm,药物分子的扩散系数Dm,单位面积体外累积释放量Q,药物在聚合物膜中的溶解度Cp,时间t,若hm较大,Dm极低则
有关瘢痕灸,叙述不正确的是()
超额剩余价值是()。
这些年来,相关部门___________遏制教育乱收费,但远未从根本上杜绝。在信息不对称、地位不平等的情况下,当事学生及家长往往___________,敢怒不敢言。填入划横线部分最恰当的一项是:
阅读材料,回答121~125题。 8月份,规模以上工业原煤生产增速回升,煤炭进口保持较高水平:原油生产增速由负转正,进口继续增加;天然气生产保持较快增长,进口持续高速增长;电力生产加快。 一、原煤生产增速回升,煤炭进口保持较高水平,市场价格小幅波动
数据操作语言是数据库管理系统的功能之一,它一般包括的操作有()。
最新回复
(
0
)