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Golden Gate Bridge
1.
Introduction
:
The
Golden Gate Bridge is a suspension
bridge spanning the Golden
Gate, the opening of the San Francisco
Bay into the Pacific Ocean. As part of both U.S.
Route
101 and California State Route 1,
it connects the city of San Francisco on the
northern tip
of
the
San
Francisco
Peninsula
to
Marin
County.
The
Golden
Gate
Bridge
was
the
longest
suspension bridge
span in the world when it was completed in 1937,
and has become one of
the most
internationally recognized
symbols
of San Francisco,
California, and of the United
States.
2.
History
2.1
Ferry
service:
Before the bridge
was built, the only practical short route between
San
Francisco and what is now Marin
County was by boat across a section of San
Francisco Bay.
Ferry
service
began
as
early
as
1820,
with
regularly
scheduled
service
beginning
in
the
1840s
for
purposes
of
transporting
water to
San
Francisco.
The
Sausalito
Land
and
Ferry
Company service, launched in 1867,
eventually became the Golden Gate Ferry Company, a
Southern
Pacific
Railroad
subsidiary,
the
largest
ferry
operation
in
the
world
by
the
late
for
railroad
passengers
and
customers
only,
Southern
Pacific‘s
automobile
ferries became
very
profitable and
important to
the regional economy. The ferry crossing
between
the
Hyde
Street
Pier
in
San
Francisco
and
Sausalito
in
Marin
County
took
approximately 20
minutes and cost US$$1.00 per vehicle, a price
later reduced to compete
with
the
new
bridge.
The
trip
from
the
San Francisco Ferry
Building
took
27
minutes.
Many
wanted
to
build
a
bridge
to
connect
San
Francisco
to
Marin
County.
San
Francisco
was the largest
American city still served primarily by ferry
boats. Because it did not have a
permanent
link
with
communities
around
the
bay,
the
city's
growth
rate
was
below
the
national
average.
Many
experts
said
that
a
bridge
couldn’t
be
built
across
the
6,700
ft
(2,042
m)
strait.
It
had
strong,
swirling
tides
and
currents,
with
water
500
ft
(150
m)
in
depth at the center of
the channel, and frequent strong winds. Experts
said that ferocious
winds
and blinding fogs would prevent construction and
operation.
2.2
Conception:
Although the idea of a bridge spanning
the Golden Gate was not new, the
proposal
that
eventually
took
place
was
made
in
a
1916
San Francisco Bulletin
article
by
former
engineering student James Wilkins. San Francisco's
City Engineer estimated the cost
at
$$100
million,
impractical
for
the
time, and
fielded
the
question
to
bridge
engineers
of
whether
it
could
be
built
for
less.
One
who
responded,
Joseph Strauss
, was
an
ambitious
but
dreamy engineer and poet who had, for his
graduate thesis
, designed a
55-mile (89 km)
long railroad bridge
across the
Bering Strait
.At
the time, Strauss
had completed some
400
drawbridges
—
most
of
which
were
inland
—
and
nothing
on
the
scale
of
the
new
project.
Strauss's initial drawings were for a
massive
cantilever
on each
side of the strait, connected
by
a
central
suspension
segment,
which
Strauss
promised
could
be
built
for
$$17
million.
Local
authorities agreed to proceed only on the
assurance that Strauss alter the design and
accept input
from
several consulting project
experts.[
citation needed
]
A
suspension-bridge
design was considered the most
practical, because of recent advances in
metallurgy
.Strauss
spent more than a
decade
drumming
up support
in
Northern
California. The bridge faced
opposition, including litigation, from
many
sources. The
Department
of War
was concerned
that
the
bridge
would
interfere
with
ship
traffic;
the
navy
feared
that
a
ship
collision
or
sabotage
to
the
bridge
could
block
the
entrance
to
one
of
its
main
harbors.
Unions
demanded guarantees that local workers
would be favored for construction jobs.
2.3
Finance:
The
Golden Gate
Bridge and
Highway
District
,
authorized
by
an
act
of
the
California
Legislature
, was incorporated in 1928
as the official entity to
design,
construct,
and
finance
the
Golden
Gate
Bridge.
However
,
after
the
Wall
Street Crash of 1929
,
the
District
was
unable
to
raise
the
construction
funds,
so
it
lobbied
for
a
$$30
million
bond
measure
. The bonds were
approved in November 1930, by votes in the
counties affected by
the bridge. The
construction budget at the time of approval was
$$27 million. However, the
District was
unable to sell the bonds until 1932, when
Amadeo Giannini
, the founder
of San
Francisco
–
based
Bank of America
, agreed on
behalf
of
his bank to
buy the entire issue
in
order to help the local economy.
2.4
Opening
festivities:
The
bridge-opening
celebration
began
on
May
27,
1937
and
lasted for one week. The day before
vehicle traffic was allowed, 200,000 people
crossed by
foot and roller skate. On
opening day, Mayor Angelo Rossi and other
officials rode the ferry
to Marin, then
crossed the bridge in a motorcade past three
ceremonial
a
blockade
of
beauty
queens
who
required
Joseph
Strauss
to
present
the
bridge
to
the
Highway District before allowing him to
pass. An official song,
Golden
Gate
on
the
Golden
Gate
Bridge
entitled
Mighty
Task
is
done.
The
next
day,
President
Roosevelt pushed a button in
Washington, D.C. signaling the official start of
vehicle traffic
over the Bridge at
noon. When the celebration got out of hand, the
SFPD had a small riot in
the
uptown
Polk
Gulch
area.
Weeks
of
civil
and
cultural
activities
called
Fiesta
followed. A
statue of Strauss was moved in 1955 to a site near
the bridge.
3.
Design and Construction
3.1
Designer:
Joseph Strauss,
Alvin Mauro, Charles Rhys Evans, Leon Moisafe.
3.2
Structure:
The weight of the roadway is hung from
two cables that pass through the two
main towers and are fixed in concrete
at each end. Each cable is made of 27,572 strands
of
wire.
There
are
80,000
miles
(129,000 km)
of
wire
in
the
main
cables.
The
bridge
has
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