The Golden Gate Bridge—50 Years Old
SOME thought it was a mild earthquake! But no, it was the effect of the wind plus the weight and movement of an estimated 250,000 people who packed the deck of San Francisco’s Golden Gate Bridge for its 50th anniversary on May 24, 1987. Another 500,000 crowded the bridge approaches. Engineers hastily calculated that the bridge could support the weight.
With a main span of 4,200 feet, the Golden Gate was the world’s longest suspension bridge at its completion in 1937. The tallest ships in the world can pass safely under the elevated highway arching 19 stories above the water.
A total of 80,000 miles of wire compose the two cables from which the bridge is suspended. Each one is 3 feet in diameter and 7,650 feet long, and has an estimated ultimate tensile strength of 200 million pounds.
Because of the excellent design and continuing maintenance, it is estimated that the bridge will have a life of 200 years.