Construction of the famous Gateway Arch in St. Louis began on February 12, 1963, and was completed in 1965. It was a unique project in scope, design and construction.
Designed to be 630 feet tall and 630 feet wide, the arch is made of sections of stainless-steel equilateral triangles with 54-foot sides at the base, tapering to 17-foot sides at the top. Each section has an inner steel wall that allows for reinforced concrete to be poured between the skin of the arch and the inner steel wall. The north and south bases of the arch rest on concrete supports, with a visitor center built underground between the two legs of the arch. When it was completed, a tram was installed in the hollow chamber inside the arch. Millions of tourists have taken that tram to the top of the arch, where windows afford a wonderful view.
As you may have realized, the Occupational Safety and Health Act of 1970 was not signed into law until five years after the arch was completed. Actuarial tables used for estimating the arch’s construction costs included funds for 13 worker fatalities during construction. As it turned out, there were zero worker fatalities during construction of the arch.