Bridge Design and Construction Statistics
Bridge Length, Width, Height, Weight
Bridge Deflection, Load Capacity
Main Tower Stats
Main Cable Stats
Suspender Rope (vertical ones) Stats
Concrete Quantities
Structural Steel Quantities
Total length of Bridge including approaches from abutment to abutment: 1.7 miles = 8,981 ft = 2,737 m
Total length of Bridge including approaches from abutment to abutment, plus the distance to the Toll Plaza: 9,150 ft = 2,788 m
Length of suspension span including main span and side spans: 1.2 miles = 6,450 ft = 1,966 m
Length of main span portion of suspended structure (distance between towers): 4,200 ft = 1,280 m
Length of one side span: 1,125 ft = 343 m
Width of Bridge: 90 ft = 27 m
Width of roadway between curbs: 62 ft = 19 m
Width of sidewalk: 10 ft = 3 m
Clearance above mean higher high water: 220 ft = 67 m
Total weight of each anchorage: 60,000 tons = 54,400,000 kg
Original combined weight of Bridge, anchorages, and approaches: 894,500 tons = 811,500,000 kg
Total weight of Bridge, anchorages, and approaches (1937): 894,500 tons = 811,500,000 kg
Total weight of Bridge, anchorages, and approaches (1986)*: 887,000 tons = 804,700,00 kg*
Weight of Bridge, excluding anchorages and approaches, and including the
suspended structure, main towers, piers and fenders, bottom lateral system and orthotropic
redecking (1986): 419,800 tons = 380,800,000 kg*
* The total bridge weight listed for 1986 includes the reduction in weight due to the redecking in 1986. The weight of the original reinforced concrete deck and its supporting stringers was 166,397 tons (150,952,000 kg). The weight of the new orthotropic steel plate deck, its two inches of epoxy asphalt surfacing, and its supporting pedestals is now 154,093 tons (139,790,700 kg). This is a total reduction in weight of the deck of 12,300 tons (11,158,400 kg), or 1.37 tons (1133 kg) per lineal foot of deck.
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Maximum transverse deflection, at center span:
27.7 ft = 8.4 m
Maximum downward deflection, at center span:
10.8 ft = 3.3 m
Maximum upward deflection, at center span: 5.8 ft = 1.77 m
Live load capacity per lineal foot:
4,000 lbs. = 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:
- 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;
- 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
- 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.
The Golden Gate Bridge has two main towers that support the two main cables.
Height of tower above water:
746 ft = 227 m
Height of tower above roadway:
500 ft = 152 m
Tower base dimension (each leg):
33 x 54 ft = 10 x 16 m
Load on each tower from main cables:
61,500 tons = 56,000,000 kg
Weight of both main towers:
44,000 tons = 40,200,000 kg
Transverse deflection of towers:
12.5 inches = 0.32 m
Longitudinal deflection of towers:
shoreward: 22 in = 0.56 m and
channelward: 18 in = 0.46 m
The south tower foundation depth below mean low water is:
110 ft = 34m
To build south tower pier to support the south tower, construction workers
pumped 9.41 million gallons or 35.6 million liters of water out of the
fender that was constructed first.
The Golden Gate 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 746-foot main towers in huge steel castings called saddles.
Diameter of one main cable including the exterior wrapping: 36 3/8 in. = .92 m
Length of one main cable: 7,650 ft = 2,332 m
Total length of galvanized steel wire used in both main cables: 80,000 mi = 129,000 km
Number of galvanized steel wires in one main cable that are 0.192 inches in diameter: 27,572
Number of bundles or strands of galvanized steel wire in one main cable: 61
Weight of both main cables, suspender cables and accessories: 24,500 tons = 22,200,000 kg
The galvanized steel 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.
The galvanized steel wire used for the main cables is carbon steel with the following average chemical composition and physical properties:
| Ladle test results (specified) |
C: |
0.81% (0.85) |
Mn: |
0.66% (---) |
P: |
0.026% (0.04) |
S: |
0.028% (0.04) |
Si: |
0.24% (---) |
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| Tested properties (specified) |
Tensile Str, |
Fu = 235,600 psi (220,000 psi min) |
Yield Str, |
Fy = 182,600 psi (160,000 psi min) |
| Elongation in 10" at rupture = 6.3% (4.0% min) |
Suspender Rope (vertical ones) Stats
The Golden Gate Bridge has a total of 250 pairs of vertical suspender ropes. Each suspender rope is 2 11/16 in. in diameter. All of the ropes were replaced between 1972 and 1976, with the last rope replacement completed on May 4, 1976.
Concrete Quantities
| |
Cu. yd. |
Cu. m. |
| San Francisco Pier and Fender |
130,000 |
99,400 |
| Marin Pier |
23,500 |
18,000 |
| Anchorages, Pylons, and Cable Housing |
182,000 |
139,160 |
| Approaches |
28,500 |
21,800 |
| Paving |
25,000 |
19,115 |
Structural Steel Quantities
| |
Tons |
Kg. |
| Main Towers |
44,400 |
40,280,000 |
| Suspended Structure |
24,000 |
21,772,000 |
| Anchorages |
4,400 |
3,991,000 |
| Approaches |
10,200 |
9,250,000 |
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