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The main river span is 336 metres (1,102 ft) in length, and the height above the water is 58 metres. The total length of the bridge is 2,582.6 metres (8,473.1 ft). It is the third longest in Australia behind the Houghton Highway and the Hornibrook Bridge, and is twice as long as the Sydney Harbour Bridge.
The bridge passes over Westgate Park, a large environmental and recreational reserve created during the bridge's construction (Wikipedia)."
"‘... the most tragic industrial accident in the history of Victoria.’
(Report of Royal Commission into the failure of West Gate Bridge, VPRS 2591/P0, unit 14)
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Thirty-five workers lost their lives that day: many others were injured. Most victims were those working on top of the bridge at the time of the collapse. Some men were lucky enough to be on their morning break away from the site; others simply ran out of the way before the bridge fell on top of them (Victorian Archives Centre)."
Wednesday, October 14, 1970: The unbolting of 4-5 Splice on 10-11 North
"On Wednesday 14th October, Ward (D Ward, M.I.C.E., Section Engineer, Freeman Fox and Partners, West Side ) gave formal written instructions for work to be done (to straighten the buckle on span 10-11 "without further delay"). The instructions refers first to the necessity to complete the bolting of the No. 4 diaphragm; unbolting the 4-5 splice is to be done with the object of making possible the completion of the diaphragm connection.
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Eventually about 30 bolts were removed from the box 5 side of the splice, extending from the longitudinal centre line to within about 2 feet of the inner web. Also about seven bolts had been removed from box 4 side of the splice, all close to the longitudinal centre line. The bulge had flattened from about 3.5 inches initially to about 1 1/8 inches, but adjacent to the longitudinal centre line the sliding movement was said to have been so great that some holes were completely blind.
At this stage, a dramatic change took place and the signs of distress for which Ward had been on guard suddenly appeared. First the vicious buckle which up to that stage had been limited to the inner upper panel spread into the adjacent two outer upper panels. This was accompanied by the buckling failure of the upper part of the winner web plate.
About this time, Ward and other witnesses say that they felt a gentle settlement of the north half span of the bridge (www.westgatebridge.org)."
Thursday, October 15, 1970: The Collapse
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Hindshaw arrived on the West span accompanied by Crossley. Hindshaw rapidly assessed the situation which superficially did not appear to be deteriorating. He was nevertheless gravely concerned with what was clearly a potentially dangerous situation and decided to ask Hardenberg's advice. Hindshaw telephoned Hardenberg (Gerit Hardenberg, M.C.E., Senior Representative of Werkspoor-Utrecht, Wescon and WSC in Melbourne) and gave him a brief sketch of the situation asking him to come over. The last thing Hardenberg heard on the phone was as if Hindshaw was thinking out aloud, "Shall I get the bods off?"
Almost immediately after that telephone conversation at 11:50 am, span 10-11 collapsed. Among those who died were Hindshaw, Crossley and Tracy (William Tracy, B.C.E, Section Engineer, JHC, West Side) (www.westgatebridge.org)."
Extracts from Report of the Royal Commission into the Failure of West Gate Bridge (1971, Victoria)
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Bridge Span Collapses; 24 Killed
MELBOURNE, Australia (AP)--Twenty-four workmen were killed and 19 injured today when a 2,000-ton section of a bridge under construction in Melbourne fell 134 feet to the ground. Twenty-five other workmen were missing, authorities said.
The collapse halted work on what is to be Australia's largest bridge, over a mile long spanning the Yarra River in the southern part of Melbourne. Known as the West Gate Bridge, its eight lanes are expected to carry 30,000 cars and trucks daily. Completion was scheduled for next year.
Within hours of the accident, unions withdrew their men from the $47 million project and Premier Sir Henry Bolte of Victoria State ordered an investigation into the disaster.
About 70 welders were on the prefabricated steel and concrete span when it gave way and thundered down on construction sheds along the riverbank where other workers were eating their lunches.
A fire broke out, and fire engines and every available ambulance were ordered to the scene. Three huge mobile cranes were moved in to lift debris.
"The bloody thing cracked in the middle," said one of the injured welders. "I was on top of it."
Work on the bridge was halted temporarily two months ago so that its steel framework could be strengthened. This followed the collapse of part of the similarly constructed Milford Haven Bridge in Wales on June 2 in which four men died. The consulting engineering firm of Freeman Fox and Parners was employed on both projects.
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VPRS 24/P3 Inquest Deposition Files, unit 120. Source: http://www.prov.vic.gov.au/exhibs/westgate/024-p3-120-010-150-02.htm.
Thursday, October 15, 1970: The Aftermath
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‘Rescuers worked all afternoon and far into the night, always in horrifying conditions, often in peril of death or injury themselves. A fire broke out as a result of spilled diesel oil igniting; while quickly extinguished, the fire added to the difficulties of rescue work … All that was humanly possible to save life and mitigate the suffering of the injured, was undoubtedly done.’
(Report of Royal Commission, VPRS 2591/P0, unit 14)
An expert technical committee was immediately established to investigate the scene. The following morning, amid nationwide grief and horror, then Premier Sir Henry Bolte announced the establishment of a royal commission to investigate the cause of the collapse. Its report, tabled in parliament in 1971, left no party associated with the collapse blameless and stated that:
‘Error begat error … and the events which led to the disaster moved with the inevitability of a Greek Tragedy.’
(Report of Royal Commission, VPRS 2591/P0, unit 14)
The government’s involvement in the West Gate Bridge project, from its conception in the early 1960s through to its troubled construction and eventual completion in 1978 is documented across several agencies, ministerial portfolios and statutory bodies (http://www.prov.vic.gov.au/exhibs/westgate/disaster.htm)."