15篇文章貫通六級詞匯MP3（字幕版）Unit12-Part1
UNIT12
The American Dream
The dream to construct a building
to house everyone and everything
connected with world trade
began in the early 1960's.
After much deliberation，
Minoru Yamasaki was commissioned
over more than a dozen other architects
to work with the firm of Emery Roth
and Sons to design this massive edifice.
His task was evident:
the building must have
twelve million square feet of floor space
on a sixteen acre parcel of land,
accommodate the new facilities
for the Hudson tubes and subway connections,
and be done within the 500 million dollar budget.
The relatively small site
combined with the vast space
needs meant that
the only way to go was up.
The development would dwarf its neighbors
and change the New York landscape
and skyline at the bottom of Manhattan.
In order to accommodate
the nine million square feet of office space,
Yamasaki made the decision
that a twotower development would be best.
This would serve the dual purpose
of giving sufficient office area
on each floor and allowing a manageable structural system
while taking advantage of the superb views.
The twin towers would be 110 floors each,
rising to a height of 1,353 feet (412 meters).
From the observation decks
at the tops of the towers
it would be possible to see 45 miles
in every direction.
When asked why he designed two 110-storey buildings
instead of one 220-storey building,
he replied, flippantly, “
I didnt want to lose the human touch.”
The first act in the construction process
was the excavation.
The 1.2 million cubic yards of earth
and rock that were removed
were used to create 23 acres of fill
in the Hudson River adjacent to the W.T.C. site.
This landfill project was subsequently developed
as Battery Park. The excavation,
besides providing the foundation
for this enormous construction,
would house parking garages,
subway terminals and tubes,
and shopping concourses.
Yamasaki believed that
all buildings must be strong
in the context of being dominant.
He felt that each building should
“be a monument to the virility of our society”.
The structural system,
while possessing this strength,
is also impressively simple.
The 208-foot front wall
is essentially a pre-assembled steel web,
with columns on 39inch centers,
providing the wind bracing necessary
for a building of this height,
allowing the central core
to take only the gravity loads.
This very light,
economical configuration would result in
keeping the wind bracing
in the most efficient place,
the outside shell of the building.
In this way, the wind force
would not be transferred
through the floor membrane to the core.
Thirtythree inch deep floors
made of prefabricated steel trusses
would act as supports to stiffen the outside walls
against the buckling forces
of the windload pressures.
There would be no interior columns
in the office spaces,
an amazing feat
as there would be 40 000 square feet
of office space on each of the upper floors.
In total, there would be seven buildings
in the complex;
the twin towers standing 110 stories high ,
four smaller towers,
and a central plaza.
Also, there would be seven underground levels
containing services,
shopping, parking garages and a subway station.
When completed, there would be
ten million square feet of leasable space,
or an acre of rentable space
on each floor of each tower.
The elevator system was intended to be fast,
efficient,and space saving.
Express elevators opening onto the forty-first
and seventy-fourth floors
would serve the sky lobbies.
From these floors and from the plaza,
four banks of elevators would
carry passengers to each of the three zones.
Tenders posted, contractors hired,
and the preliminary materials purchased,
the groundbreaking ceremony
was held on August 5, 1966.
Some offices were ready for occupancy
in 1970 but the ribbon cutting ceremony
wasn't held until April 4, 1973.
Final cost 750 million dollars.
The institution of the W.T.C.
would become a symbol of commerce
and economic superiority to the world.
International businesses recognized
that it would be advantageous
to have offices there.
Thus, the working population of the W.T.C.
would incorporate a cross-section of nationalities,
not just Americans.
The buildings would be occupied
by as many as
fifty thousand people daily during the week.
Additionally,thousands of tourists
could be in the center at any given time,
visiting the restaurant,
Windows on the World,
atop One W.T.C.,
the indoor and outdoor observation decks
on Two W.T.C., as well as the shops,
exhibition pavilions,
and the 250 room hotel.
A complex of this size
is not without some problems,
including fire. Numerous small fires
and one major one on February 13, 1975
occurred over the years.
However, on February 26, 1993,
a terrorist attack on the W.T.C.
caused the largest incident ever handled
by the City of New York's Fire Department.
The blaze, resulting from
the ignition of a nitrourea bomb,
with hydrogen cylinders to add impact,
and located in the parking garage,
required the response of 84 engine companies,
60 truck companies,
and hundreds of personnel.
Firefighters maintained a presence
at the site for 28 days,
guarding against the possibility
of further fires caused by the blast.
Six people died and 1042 were injured.
The towers survived.
After this violent incident failed
in its intended purpose of destroying the W.T.C.,
who could have envisaged an assault
as disastrous as the one inflicted on it
and the United States on September 11, 2001?
Who could have conceived an attack
so vicious it would eclipse
almost every manmade catastrophe?
Who could have foreseen that
the American dream would
blur into a terrible nightmare?
At 8∶45 a.m. New York local time,
a hijacked 767 commercial airliner
with a full load of jet fuel
for a transcontinentalflight collided with One W.T.C.,
The north tower,
with enough impetus to carry it
through to the opposite side.
Initially, terrorism was not a consideration
in the mind of the public.
This was merely a dreadful accident.
