Exhibit Area 1
(Plaza area)
Welcome Sign [main directory]
How the Bridge Spans the Golden Gate
Bridge Aesthetics - Art Deco on a Grand Scale
Tall and Strong - The Bridge Towers
Steel, Fog, Salt, Rust, and Paint

Exhibit Area 2
(near flagpole)
How the Bridge Vibrates
Foghorns

Exhibit Area 3
(West side of Bridge near underpass)
Historic Preservation: Lattice Strut Retrofit
Historic Preservation: Isolator Seismic Retrofit

Exhibit Area 4
(inside Battery area)
History: Design and Construction of the Bridge
Suspension Cable Tension vs. Tower Height
Battery Lancaster - Defending the Golden Gate

Exhibit Area 5
(along bike path to lower parking lot)
Bridge Deck Aerodynamics
Bridge Deck Torsional Resistance Retrofit
Wind Speed and Wind Pressure

Exhibit Area 6
(near Pavillion)
LIFETILES: animated construction of the Bridge
Braille / Tactile Model of the Bridge



Project Partners

GGBHTD
Golden Gate Bridge,
Highway and Transporation District



CUREE

Consortium of Universities for Research
in Earthquake Engineering

Main Menu : Exhibit Area 4

History of the Design and Construction of the Bridge

SPINNING THE MAIN CABLES

By mid-1935, the north and south towers stood ready to support the two main cables. Each of the cables measured a little over 3 feet (about 1 meter) in diameter and weighed 12,000 tons. They were far too heavy to carry across the Golden Gate Strait on barges and lift up to the tops of the towers.

The cables were constructed high in the air using a process called cable spinning, which was invented by John A. Roebling in the 1800s. The company he founded made cables for the Golden Gate Bridge.

To spin the cables, workers pulled a wire, about as thick as a pencil, from the concrete anchorage at one shore, up and over both towers, and on to the other anchorage. The wire was then secured and sent back. It took many back-and-forth trips to place the 27,572 wires that are in each cable. Individual wires were grouped into heavier strands and compacted together to form the finished cable. The spinning of the cables took just six months and nine days, setting records for speed and efficiency.

The entire weight of the roadway deck crossing the Gate could then be suspended from the two cables – that’s why it is called a suspension bridge.

MORE IMAGES

Known as spinning, thin wires were drawn back and forth across the strait by steel wheels.

Image courtesy of the San Francisco Historical Society - Huggins Collection - CHS.Huggins.012

A hydraulic press compacted the thin wire strands into one large cable.

Image courtesy of the San Francisco History Center, San Francisco Public Library

Workers tighten bolts to clamp a band to the main cable. Steel suspender ropes were later placed over the top of the cable band and extended down to support the deck structure.

A popular exhibit at the Bridge is this full-size cross section of the main cable, clearly showing the 27,572 parallel wires.

All images property of the Golden Gate Bridge, Highway and Transportation District (unless otherwise indicated).

For more information -

Photos of Cable Spinning
http://goldengatebridge.org/photos/maincablespinning.php

Video of the Golden Gate Bridge Under Construction - 1936
http://www.youtube.com/watch?v=fAvOnhBt0BY


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Last updated: 11.16.12