单选题
When I was still an architecture student, a
teacher told me, "we learn more from buildingsthat fall down than from buildings
that stand up." What he meant was that construction is as muchthe result of
experience as of theory. Although structural design follows established
formulas, theactual performance of a building is complicated by the passage of
time, the behavior of users, thenatural element s--and unnatural events. All are
difficult to simulate. Buildings, unlike cars,can' t be
crash-tasted. The first important lesson of the World Trade
Center collapse is that tall buildings canwithstand the impact of a large
jetliner. The twin towers were supported by 59 perimeter columnson each side.
Although about 30 of these columns, extending from four to six
floors, weredestroyed in each building by the impact, initially both
towers remained standing. Even so, thedeath toll (代价) was appalling--2235 people
lost their lives. I was once asked, how tall buildings should
be designed given what we'd learned from theWorld Trade Center collapse. My
answer was, "lower". The question of when a tall buildingbecomes unsafe is easy
to answer. Common aerial fire-fighting ladders in use today are 100 feethigh and
can reach to about the 10th floor, so fires in buildings up to 10 stories high
can be foughtfrom the exterior (外部) . Fighting fires and evacuating occupants
above that height depend onfire stairs. The taller the building, the longer it
will take for firefighters to climb to the scene of thefire. So the simple
answer to the safety question is"lower than 10 stories." Then
why don't cities impose lower height limits? A 60-story office building does not
havesix times as much rentable space as a 10-story building. However, all things
being equal, such abuilding will produce four times more revenue and four times
more in property taxes. So cuttingbuilding heights would mean cutting city
budgets. The most important lesson of the World Trade Center
collapse is not that we should stopbuilding tall buildings but that we have
misjudged their cost. We did the same thing when weunderestimated the cost of
hurtling along a highway in a steel box at 70 miles per hour. It took manyyears
before seat belts, air bags, radial tires, and antilock brakes
became commonplace. Atfirst, cars simply were too slow to warrant concern.
Later, manufacturers resisted these expensivedevices, arguing that consumers
would not pay for safety. Now we do willingly.
单选题
The first paragraph tells us that______
A. architecture is something more out of experience than out of theory
B. architecture depends just as much on experience as on theory
C. it is safer for people to live in old buildings
D. we learn not so much from our failures as from our success