A complete presentation about the legendary Golden Gate bridge.

2. INTRODUCTION
HISTORY
PRESENT
TIME-LINE
KEY-DATES
BRIDGE DESIGN
FACTS
FUTURE
AESTHETICS
PHOTOGRAPHS

5. The Golden Gate Bridge was the largest suspension
bridge in the world When it was completed in 1937
and has become an internationally recognized
symbol of San Francisco and the united states.
Chief Engineer of golden gate bridge was Joseph B.
Strauss.
The Golden Gate Bridge is a suspension bridge
spanning the Golden Gate, the opening into the San
Francisco Bay from the Pacific Ocean. It connects
the city of San Francisco on the northern tip of the
San Francisco Peninsula to Marin County as part of
US Highway 101 and California State Highway 1.
NTRODUCTIONI

6. HISTORY
Rope Bridge: A bridge constructed chiefly
of rope. In its simplest form, it can be one or
two ropes that bridge a river, enabling the
traveller to be supported in their crossing
and not be swept away. One rope above
another, for feet and hands, may be referred
to as a commando bridge.
Inca Rope Bridge: Inca rope bridges were
simple suspension bridges over canyons
and gorges (pongos) to provide access for
the Inca Empire. Bridges of this type were
suitable for use since the Inca people did not
use wheeled transport - traffic was limited to
pedestrians and livestock.

7. HISTORY
Simple Suspension Bridge: A simple suspension bridge is an early
bridge type and is still formed from native materials, chiefly grass rope,
in some areas of South America. These rope bridges must be
periodically renewed owing to the limited lifetime of the materials, and
rope components are made and contributed by families as
contributions to a community endeavor.

8. PRESENT
Suspension Bridge: The main forces in a
suspension bridge are tension in the main
cables and compression in the pillars. Since
almost all the force on the pillars is
vertically downwards and they are also
stabilized by the main cables, they can be
made quite slender.
Assuming a negligible cable weight compared to the deck and vehicles being
supported, a suspension bridge's main cables will form a parabola (very similar
to a catenary, the form the unloaded cables take before the deck is added). This
can be seen from the cable's constant gradient increase with linear (deck)
distance, this increase in gradient at each connection with the deck providing a
net upward support force. Combined with the relatively simple constraints
placed upon the actual deck, this makes the suspension bridge much simpler to
design and analyze than a cable stayed design, where the deck is in
compression.

9. PRESENT
Advantages over other bridge types :
1. The center span may be made long in proportion to the materials
required, allowing the bridge to economically span a very wide canyon or
waterway.
2. It can be built high over water to allow the passage of tall ships.
3. Neither temporary central supports nor access from beneath is
required for construction, allowing it to span a rift or waterway.
4. Being flexible it can flex under wind and seismic conditions, where a
more rigid bridge would have to be made stronger and heavier.
5. Since they can provide the same strength and stability of other design
schemes with less weight and bulk suspension bridges are often less
expensive to construct and maintain.
Other Bridges: cantilever bridge, cable stayed bridge, beam bridge,
and arch bridge.

10. Pre-Historic Times
Iron became
known to man
Abraham Darby-I
leased a furnace
at Coalbrookdale
1709 1747
Smelting of iron ore
with coke instead of
charcoal
1755
Use of cast iron
utensils for the
first time
1767
First iron rails
were cast
1767
First iron bridge
was built-The
Severn Bridge
1937
Golden Gate Bridge
at San Francisco
TIME LINET

11. KEY DATES
1872 Earliest discussion of building a bridge across the Golden Gate Strait
Joseph B. Strauss submits his final plans for the Golden Gate
Bridge to the District Board of Directors.
August 27,
1930
Voters within the 6 counties of the District approve a $35 million
bond issue to finance construction of the Golden Gate
Bridge. The vote is 145,657 YES and 46,954 NO. On January
5, 1933, Construction of the Golden Gate Bridge begins.
November
4, 1930
Golden Gate Bridge opens to pedestrian traffic.
May 27,
1937
Golden Gate Ferry begins service between Sausalito and San
Francisco.
August 15,
1970
Golden Gate Transit service begins.January 1,
1972
One billionth car crosses the Golden Gate Bridge.
February
22, 1985
Construction is complete on the replacement of the original
Golden Gate Bridge roadway with a modern orthotropic steel
plate deck.
August 15,
1985

12. KEY DATES
Golden Gate Bridge designated a double-fine-zone.September 13,
1996
United States Postal Service unveils Golden Gate Bridge
commemorative stamp.
September 3,
1998
Golden Gate Bridge turns 65 years old.May 27,
2002
New Bridge toll rates: $5.00 cash, $4.00 FasTrak and $2.50 per
axle (for vehicles exceeding two axles)
September 1,
2002

13. BRIDGE DESIGN
Length, Width, Height, Weight
Total length of Bridge including approaches :2,737 m
Length of suspension span including main span and side spans : 1,966 m
Length of main span portion of suspended structure : 1,280 m
Length of one side span : 343 m
Width of Bridge : 27 m
Width of roadway between curbs : 19 m
Width of sidewalk : 3 m
Clearance above mean higher high water : 67 m
Total weight of each anchorage : 54,400,000 kg
Original combined weight of Bridge, anchorages, and approaches: 811,500,000 kg
Total weight of Bridge, anchorages, and approaches (1986) : 804,700,000 kg
Weight of Bridge, excluding anchorages and approaches, and
including the suspended structure, main towers, piers and
fenders, bottom lateral system and orthotropic redecking :380,800,000 kg

14. BRIDGE DESIGN
Bridge Deflection, Load Capacity
Max transverse deflection, at center span : 8.4 m
Maximum downward deflection, at center span : 3.3 m
Maximum upward deflection, at center span : 1.77 m
Live load capacity per lineal foot : 1,814.4 kg
As an example of how the Bridge is built to move, during the winter storms in 1982,
the main span bowed approximately 6 to 7 feet
The three maximum deflections noted above at the center of the suspension bridge
are due to the following loading conditions:
1. The transverse deflection is due to a sustained transverse wind load. The maximum
transverse movement of 27.7 ft is based on the maximum allowable longitudinal movement of
the wind locks at the support towers;
2. The maximum downward deflection is due to a condition with maximum live load on the center
span, no live load on the side spans and maximum design temperature to elongate the main
cables; and
3. The maximum upward deflection is due to a condition opposite to condition 2 above, with
maximum live load on side spans, no live load on center span and minimum design temperature
to shorten the cable length.

15. BRIDGE DESIGN
Main Tower Stats
The Golden Gate Bridge has two main towers that support the two main cables.
Height of tower above water : 227 m
Height of tower above roadway : 152 m
Tower base dimension (each leg) : 10 x 16 m
Load on each tower from main cables: 56,000,000 kg
Weight of both main towers : 40,200,000 kg
Transverse deflection of towers : 0.32 m
Longitudinal deflection of towers: Shoreward: 0.56 m Channel ward: 0.46 m
The south tower foundation depth below mean low water is: 34m
To build south tower pier to support the south tower, construction workers pumped
35.6 million liters of water out of the fender that was constructed first.

16. BRIDGE DESIGN
Main Cable Stats
The Bridge has two main cables which pass over the tops of the two main towers and
are secured at either end in giant anchorages.
The main cables rest on top of the towers in huge steel castings called saddles.
Diameter of one main cable with wrapping : .92 m
Length of one main cable : 2,332 m
Total length of wire used in both main cables : 129,000 km
No. of galvanized wires in one main cable that are 0.192” in diameter: 27,572
Number of strands in one main cable : 61
Weight of both Main Cables, Suspender Cables & Accessories: 22,200,000 kg
The wire comprising each main cable was laid by spinning the wire using a loom-type
shuttle that moved back and forth as it laid the wire in place to form the cables.
The spinning of the main cable wires was completed in 6 months and 9 days.

17. BRIDGE DESIGN
Concrete Quantities Cu. m.
San Francisco Pier and Fender 99,400
Marin Pier 18,000
Anchorages, Pylons, and Cable
Housing
139,160
Approaches 21,800
Paving 19,115
Structural Steel Quantities Kg.
Main Towers 40,280,000
Suspended Structure 21,772,000
Anchorages 3,991,000
Approaches 9,250,000

18. ACTSF
WHY THE NAME ‘GOLDEN GATE’ ?
The Golden Gate Strait is the entrance to the
San Francisco Bay from the Pacific Ocean.
The strait is approximately three-miles long by one-mile wide with
currents ranging from 4.5 to 7.5 mile.
It is generally accepted that the strait was named "Chrysopylae", or
Golden Gate, by John C. Fremont, Captain, topographical Engineers
of the U.S. Army.
It reminded him of a harbor in Instanbul named Chrysoceras or
Golden Horn.

19. FACTS
HOW MANY PEOPLE WORKED ON THE BRIDGE DURING ITS
CONSTRUCTION?
We do not have the exact employment figures. The Bridge was built
by 10 different prime contractors and their subcontractors.
WERE HARD HATS USED DURING CONSTRUCTION?
Yes they were and here is how they came to be. The E.D. Bullard Company
was founded in 1898 in San Francisco, CA, where the firm manufactured
equipment for miners in western states. It was considered the first "hard
hat," which revolutionized construction and mine worker safety.

20. FACTS
WHAT WOULD IT COST TO BUILD THE GOLDEN GATE BRIDGE
TODAY?
The cost to construct a new Golden Gate Bridge would be
approximately $1.8 billion in 2005 dollars. The total price depends
on a many factors including the extent of the environmental reviews
and the cost of labor and materials.WHERE WAS THE STEEL FABRICATED FOR THE CONSTRUCTION
OF THE GOLDEN GATE BRIDGE?
Manufactured by Bethlehem Steel in plants in Trenton, New Jersey
and Sparrows Point, Maryland and in plants in three Pennsylvania
towns: Bethlehem, Pottstown, and Steelton.
WHAT'S THE HALFWAY-TO-HELL CLUB?
The most conspicuous precaution was the safety net, suspended
under the floor of the Bridge from end to end. During construction,
the net saved the lives of 19 men who became known as the "Half-
Way-to-Hell Club."

21. FACTS
DOES THE GOLDEN GATE BRIDGE HAVE THE WORLD'S LONGEST SUSPENSION
SPAN?
19981,991 metersAkashi-Kaikyo Bridge, Japan 6,532 feet
19311,067 meters3,500 feetGeorge Washington Bridge, N.Y.
19731,074 meters3,523 feetFirst Bosphorous, Turkey
19921,090 meters3,576 feetSecond Bosphorous , Turkey
19881,100 meters3,609 feetMinami Bisan-Seto Bridge, Japan
19571,158 meters3,800 feetMackinac Straits Bridge, Michigan
19971,210 meters3,970 feetHigh Coast Bridge, Sweden
19371,280 meters4,200 feetGolden Gate Bridge, San Frs.
19641,299 meters4,260 feetVerrazano Narrows Bridge, N.Y.
19971,377 meters4,518 feetTsing Ma Bridge, China
19991,385 meters4,544 feetJiangyin Yangtze Bridge, China
19811,410 meters4.626 feetHumber Bridge, England
19971,624 meters5,328 feetGreat Belt East Bridge, Denmark
Year OpenedMain Span LengthSUSPENSION BRIDGES

22. FACTS
WHAT ARE THE ORIGINAL RIVETS REPLACED WITH WHEN THEY
BECOME CORRODED?
Since 1970, as various construction projects and painting projects occur
across the Bridge, the original rivets are being replaced with
ASTM A-325 high-strength bolts of equal diameter. In the early 1970s,
corroded rivets were replaced with ASTM A-325 high-strength bolts dipped
in organic zinc rich primer prior to installation.
HAS THE GOLDEN GATE BRIDGE EVER BEEN CLOSED?
Yes, the Golden Gate Bridge has been closed due to weather conditions
only three times:
1.December 1, 1951, for three hours: gusting winds reached 69 miles per hour.
2.December 23, 1982, almost two hours: high winds of up to 70 miles per hour.
3.December 3, 1983, 3 hours and 27 minutes: Wind reached 75 miles per hour.
All three times the bridge survived and suffered no structural damages.
FACTSF

23. FUTURE
Self-Anchored Suspension Bridge: It is a
suspension bridge in which the main cables
do not attach to the ground via large
anchorages; instead, the main cables
attach to the ends of the road deck, which
experiences compression equal to the
tension in the cables. The result of this
design is that the bridge does not exert any
horizontal pulling forces on the ground; the
bridge foundations need only support the
bridge's weight. Therefore, the self-
anchored suspension bridge design is well-
suited for construction atop elevated piers,
or in areas of unstable soils where
anchorages would be difficult to construct.
Suspension bridge with the main cables
attached to the ground (black squares)
Self-anchored suspension bridge; the main
cables are attached to the end of the road deck
FUTUREF

24. ESTHETICSA
The color of the bridge is an orange vermillion called international
orange.
The color was selected by consulting Architect ILVING MORROW
Because orange color blends well with the natural surrounding yet
enhances the bridge’s visibility in fog.
The Golden Gate Bridge is painted international orange. The
international orange paint used on the Golden Gate Bridge is
specially formulated to protect the bridge from the danger of rust
from the moisture of the frequent fog that rolls in from the pacific
ocean through the Golden Gate to San Francisco Bay.
The colour of the bridge…!

25. HOTOGRAPHPPHOTOGRAPHP

26. HOTOGRAPHPPHOTOGRAPHP

27. HOTOGRAPHP

28. HOTOGRAPHP

29. ● Giedion, Sigfried, Space, Time and Architecture
● Websites:
www.wikipedia.com
www.goldengate.com
www.structure.com
www.google.com

30. Thank You…

31. GOLDEN GATE BRIDGE
Marin Anchorage
(January 1933 through February 1936)
San Francisco Anchorage
(January 1933 through February 1936)
Marin Pier
(January 1933 through June 1933)
San Francisco Trestle
(March 1933 through February 1934)
San Francisco Pier
(March 1934 through December 1934)
San Francisco Trestle Repair
(November 1933 through March 1934)
Marin Tower
(November 1933 through October 1934)
San Francisco Tower
(January 1935 through June 1935 )
Catwalk Cables
(July 1935 )
Suspension Cables
(October 1935 through March 1936)
Cable Compression
(May 1936)
Roadway Steel
(June 1936 through November 1936)
Deck Surface
(January 1937 through April 1937)
Jan, 1933 Apr, 1937
Jan, 1933 Apr, 1937
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