when was the original tappan zee bridge built
Tappan Zee Bridge Construction started in March 1952 and the bridge opened to traffic on December 15, 1955, along with a 27-mile (43 km) long section of the New York State Thruway from Suffern to Yonkers.[18][19] New York State Governor W. Averell Harriman signed a bill on February 28, 1956, to officially name the structure the Tappan Zee Bridge.[20] In 1994, the name of Malcolm Wilson was added to the bridge's name upon the 20th anniversary of his leaving the governor's office in December 1974, though it is almost never used when the bridge is spoken about colloquially.[21]
Sydney Harbour Bridge The bridge is held together by six million Australian-made hand-driven rivets supplied by the McPherson company of Melbourne,[14][15] the last being driven through the deck on 21 January 1932.[13][16] The rivets were heated red-hot and inserted into the plates; the headless end was immediately rounded over with a large pneumatic rivet gun.[17] The largest of the rivets used weighed 3.5 kg (8 lb) and was 39.5 cm (15.6 in) long.[12][18] The practice of riveting large steel structures, rather than welding, was, at the time, a proven and understood construction technique, whilst structural welding had not at that stage been adequately developed for use on the bridge.[17]