共用题干
第一篇
Can Buildings Be Designed to Resist Terrorist Attack?
In the aftermath of the terrorist attack on the World Trade Center,structural engineers are trying hard to
solve a question that a month ago would have been completely unthinkable:Can buildings be designed to
withstand catastrophic blasts inflicted by terrorists?
Ten days after the terrorist attacks on the twin towers,structural engineers from the University at Buffalo
and the Multidisciplinary Center for Earthquake Engineering Research(MCEER)headquartered at UB
traveled to ground zero as part of a project funded by the National Science Foundation.Visiting the site as
part of an MCEER reconnaissance visit,they spent two days beginning the task of formulating ideas about
how to design such structures arid to search for clues on how to do so in buildings that were damaged but still
are standing.
"Our objective in visiting ground zero was to go and look at the buildings surrounding the World Trade
Center,those buildings that are still standing,but that sustained damage,"said M.Bruneau,Ph.D."Our im-
mediate hope is that we can develop a better understanding as to why those buildings remain standing,while
our long-term goal is to see whether earthquake engineering technologies can be married to existing technolo-
gies to achieve enhanced performance of buildings in the event of terrorist attacks,"he added.
Photographs taken by the investigators demonstrate in startling detail the monumental damage inflicteed
on the World Trade Center towers and buildings in the vicinity.One building a block away from the towers
remains standing,but was badly damaged."This building is many meters away from the World Trade Center
and yet we see a column there that used to be part of that building,"explained A.Whittaker,Ph.D."The
column became a missile that shot across the road,through the window arid through the floor."
The visit to the area also revealed some surprises,according to the engineers.For example,the floor
framing system in one of the adjacent buildings was quite rugged,allowing floors that were pierced by tons of
falling debris to remain intact. " Highly redundant ductile（有延展性的）framing systems may provide a sim-
pie,but robust strategy for blast resistance,"he added.Other strategies may include providing alternate paths
for gravity loads in the event that a load一bearing column fails."We also need a better understanding of the
mechanism of collapse,"said A.Whittaker."We need to find out what causes a building to collapse and how
you can predict it."
A.Reinhorn,Ph.D.noted that"Earthquake shaking has led to the collapse of many buildings in the
past.It induces dynamic response and extremely high stresses and deformations in structural components.So-
lutions developed for earthquake-resistant design may be directly applicable to blast engineering and
terrorist-resistant design.Part of our mission now at UB is to transfer these solutions and to develop new ones
where none exist at present."
The question raised in the first paragraph is one_______.
A:that was asked by structural engineers a month ago
B:that is too difficult for structural engineers to answer even now
C:that was never imagined before the terrorist attack
D:that terrorists are eager to find a solution to

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