Designer Utah Australia | Opened 12 April 1961 | |
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Address Kings Way, Southbank VIC 3006, Australia Similar Spencer Street Bridge, Queens Bridge, Charles Grimes Bridge, Hoddle Bridge, MacRobertson Bridge | ||
The King Street Bridge takes King Street over the Yarra River in Melbourne, Victoria, Australia. The bridge continues south as an elevated viaduct, with the Crown Casino and Entertainment Complex built around it in later years.
History
The bridge was designed in 1959 by Utah Australia for the Country Roads Board, and constructed over the next two years, being opened on 12 April 1961. It was of a welded, deck-girder, suspended-span construction with spans up to 160 feet (49 m) long.
Soon after completion, on 10 July 1962, one span collapsed under the weight of a 47-ton semi-trailer, though the weight was within the bridge limits. The subsequent Royal Commission found that bridge failed with a brittle fracture on a very cold Melbourne winter day. The Commission identified the cause of girder failure was due to cracked welds. The fabricator was not familiar with welding low-alloy steel and the steel supplied was high in carbon making it difficult even for an experienced fabricator. The cracks in the welds were not discovered by inspectors of both the fabricator and the Country Roads Board. The south end of the bridge has been undergoing differential settlement between the approach ramps resting on fill, and the suspended section supported by bored piles. The embarrassing incident was widely satirised at the time; most notably by the Melbourne TV clowns Zig and Zag and was the inspiration for a Spike Milligan radio comedy.
The redesign and strengthening of the bridge was undertaken by Melbourne engineer Bruce Day who employed a series of post tension pipes and concrete counter weights.
As originally constructed the bridge had 8 lanes across the Yarra River - 2 through lanes in each direction connecting King Street to Kingsway, in addition to 2 lanes on each side that connected to Yarra Bank Road. At the south end north facing on and off ramps connected to Whiteman Street, and the running lanes from the viaduct descend to ground level, with tram route 55 emerging from City Road to the median strip. In later years the development of Crown Casino closed Yarra Bank Road, and the bridge ramps were connected to the basement carpark of the complex.