West Gate Bridge

About

The West Gate Bridge is a steel, box girder, cable-stayed bridge in Melbourne, Victoria, Australia, spanning the Yarra River just north of its mouth into Port Phillip. It carries the West Gate Freeway and is a vital link between the Melbourne central business district (CBD) and western suburbs, with the industrial suburbs in the west, and with the city of Geelong 80 kilometres (50 mi) to the south-west. It is part of one of the busiest road corridors in Australia. The high span bridge was built to allow large cargo ships to access the docks in the Yarra River. The main river span is 336 metres (1,102 ft) long, and 58 metres (190 ft) above the water. The total length of the bridge is 2,582.6 metres (8,473 ft). It is the fifth-longest in Australia, the longest being Melbourne's Bolte Bridge at 5 kilometres (3.1 mi). The West Gate Bridge is twice as long as the Sydney Harbour Bridge and is one of the highest road decks in Australia, higher than Sydney Harbour Bridge's 49 metres (161 ft). It carries up to 200,000 vehicles per day. The bridge passes over Westgate Park, a large environmental and recreational reserve created during the bridge's construction. On 15 October 1970, dozens of...

The West Gate Bridge is a 10-lane dual-carriageway freeway bridge, carrying five lanes of motor vehicle traffic in each direction. The freeway corridor (including the bridge itself) carries a very high volume and occupancy of traffic; a total of between 180,000 and 200,000 cars, trucks, and motorcycles use it per day, according to VicRoads. This makes the West Gate Bridge and West Gate Freeway one of the busiest road corridors in Australia.

As it is the only main direct link between Melbourne's CBD and the west, it is frequently congested during the morning and afternoon peaks and is constantly busy due to the number of vehicles coming in and out of the Port of Melbourne. The bridge was originally tolled but John Cain 's government made a promise at the 1985 election to discontinue tolls; this came into effect in November of that year.

The bridge is windswept as there are no significant obstructing terrain features for some distance, particularly in the quadrant from south to west, a common wind direction. This can lead to issues for motorbikes, trucks and other high-sided vehicles in higher wind speeds. Previously wind warning lights were present at the bridge approaches to control traffic (amber – bridge closed to motorbikes and high vehicles, red – closed to all traffic), but the former practice is to reduce the speed limit to 60 kilometres per hour (37 mph) or 40 kilometres per hour (25 mph) when the wind speed gets too high. This has since been replaced with a modern variable speed limit system as part of the 2008–11 upgrade.

Cyclists are prohibited from using the bridge except for special bicycle events, notably the Melbourne Summer Cycle, a fundraising event for multiple sclerosis, and the Around the Bay in a Day event that raises money for The Smith Family charity. The Westgate Punt is a foot ferry that runs directly below the bridge, taking cyclists and pedestrians across the Yarra between a jetty at Fishermans Bend near Westgate Park – Bay Trail and a jetty adjacent to Scienceworks Museum – Hobsons Bay Coastal Trail. It operates on demand, from Monday to Friday in morning and evening peaks, and on weekends and public holidays from 10:00 am to 5:00 pm.

The West Gate Bridge is a 10-lane dual-carriageway freeway bridge, carrying five lanes of motor vehicle traffic in each direction. The freeway corridor (including the bridge itself) carries a very high volume and occupancy of traffic; a total of between 180,000 and 200,000 cars, trucks, and motorcycles use it per day, according to VicRoads. This makes the West Gate Bridge and West Gate Freeway one of the busiest road corridors in Australia.

As it is the only main direct link between Melbourne's CBD and the west, it is frequently congested during the morning and afternoon peaks and is constantly busy due to the number of vehicles coming in and out of the Port of Melbourne. The bridge was originally tolled but John Cain 's government made a promise at the 1985 election to discontinue tolls; this came into effect in November of that year.

The bridge is windswept as there are no significant obstructing terrain features for some distance, particularly in the quadrant from south to west, a common wind direction. This can lead to issues for motorbikes, trucks and other high-sided vehicles in higher wind speeds. Previously wind warning lights were present at the bridge approaches to control traffic (amber – bridge closed to motorbikes and high vehicles, red – closed to all traffic), but the former practice is to reduce the speed limit to 60 kilometres per hour (37 mph) or 40 kilometres per hour (25 mph) when the wind speed gets too high. This has since been replaced with a modern variable speed limit system as part of the 2008–11 upgrade.

Cyclists are prohibited from using the bridge except for special bicycle events, notably the Melbourne Summer Cycle, a fundraising event for multiple sclerosis, and the Around the Bay in a Day event that raises money for The Smith Family charity. The Westgate Punt is a foot ferry that runs directly below the bridge, taking cyclists and pedestrians across the Yarra between a jetty at Fishermans Bend near Westgate Park – Bay Trail and a jetty adjacent to Scienceworks Museum – Hobsons Bay Coastal Trail. It operates on demand, from Monday to Friday in morning and evening peaks, and on weekends and public holidays from 10:00 am to 5:00 pm.

The notion of a Lower Yarra River Crossing has formal origins as early as 1888, when Victoria’s Public Works Department first proposed a tunnel under the Yarra. The Metropolitan Town Planning Commission 's Plan of General Development proposed a bridge for a road between Geelong Road ('west of Kororoit Creek') and Ingles St, Port Melbourne. Road routes between central Melbourne and the west were, however, bridged further north, and the usual method of crossing at the lower Yarra was via skiffs until 1912, when ferries were first instituted, the Newport steam ferry operated by the City of Williamstown taking prominence between 1931 and 1974.

The Western Industries Association was formed in August 1957 and claimed to be ‘representative of all industries in Altona, Footscray, Sunshine, Werribee and Williamstown districts’. Having formed a sub-committee to investigate a Yarra crossing, in 1958 it asked Victorian Premier Henry Bolte ‘to give urgent consideration to construction of a traffic tunnel under the Yarra.’ The Association had been told by 'shipping interests' that a bridge would not be acceptable for the crossing. The tunnel, it was suggested, would carry 30 000 cars a day; differing estimates on the capacity of the 'overtaxed' ferry suggested it could only handle between 1 200 and 2 000. The Victorian Government's response to the proposal, delivered by Commissioner for Public Works Thomas Maltby, was that the government's finances were inadequate to undertake a crossing urgently and that any such project would require private investment. In 1961 Lower Yarra Crossing Limited was formed, a non-profit company to develop the crossing. In mid-1960 it was announced that the Association would raise the money to construct the bridge with government support keeping interest rates low; the arrangement was envisaged as not, in itself, profit-making. In this year, the Western Industries Association applied to government for license to construct and operate a crossing on a toll basis.

In 1961 the Association formed Lower Yarra Crossing Ltd. Test drilling began late in that year by which point the Association once again became publicly open to the construction of a bridge, rather than a tunnel. Nevertheless Danish tunnel engineering firm Christiani and Nielson were engaged as consultants. Chief amongst the concerns regarding a tunnel was the limitation on particular goods or cargoes - notably, flammable material - that could legally, or safely, be carried through a tunnel.

In the state government's analysis, the cost of building a bridge or a tunnel would be equal, however, notwithstanding the Harbour Trust 's strong advocacy for a tunnel, it was felt by those in power that a bridge would more readily allow use by petrol tankers. In 1965, Yvonne A. Van Den Nouwelant writes, ‘the Lower Yarra Crossing Authority was granted a franchise by Act of Parliament and in 1968 construction started on the West Gate Bridge.’ It was noted by the press at the time that the location of the bridge's eastern approaches would require the removal of the Fishermen's Bend airstrip.

Two years into construction of the bridge, at 11:50 am on 15 October 1970, the 112-metre (367-foot) span between piers 10 and 11 collapsed and fell 50 metres (164 feet) to the ground and water below. Thirty-five construction workers died and eighteen were injured, and it remains Australia's worst industrial accident. Many of those who died were on lunch break beneath the structure in workers' huts, which were crushed by the falling span. Others were working on and inside the span when it fell. The whole 2,000-tonne (4,400,000 lb) mass plummeted into the Yarra River mud with an explosion of gas, dust and mangled metal that shook buildings hundreds of metres away. Nearby houses were spattered with flying mud. The roar of the impact, the explosion, and the fire that followed, could be clearly heard over 20 kilometres (12 mi) away. On the following morning, 16 October, the Premier of Victoria, Sir Henry Bolte, announced that a Royal Commission would be set up immediately to look into the cause of the disaster. Prime Minister John Gorton, said: "I am sure the whole of Australia is shocked and saddened by the serious accident at West Gate Bridge. Please extend my deepest sympathy to all those families to whom this tragic event has brought such grief."

The Royal Commission concluded on 14 July 1971. It attributed the failure of the bridge to two causes: the structural design by designers Freeman Fox & Partners, and an unusual method of construction by World Services and Construction, the original contractors for the project.

On the day of the collapse, there was a difference in camber of 11.4 centimetres (4.5 in) between two half- girders at the west end of the span which needed to be joined. It was proposed that the higher one be weighted down with 10 concrete blocks, each weighing 8 tonnes (8.8 short tons), which were located on-site. The weight of those blocks caused the span to buckle, which was a sign of structural failure. The longitudinal joining of the half-girders was partially complete when orders were given to remove the buckle by unbolting the upper flange along the splice between boxes 4 and 5, allowing the plates forming the upper flange to slide over one another. The removal of the bolts created a stress concentration that the bridge could not withstand, owing to inadequate factors of safety in the design. The bridge collapsed approximately an hour later.

The disaster shifted the balance of industrial relations in Australia. Subsequently, unions pushed for stronger roles in safety negotiations, statutory occupational health and safety committees, and mandatory site inspections involving worker representatives. Safety training, incident reporting and grief counselling became integral parts of workplace management. In the decades since, these reforms have saved countless lives on Australian building sites.

Six twisted fragments of the collapsed bridge can be found in the West Gate garden at the engineering faculty of Monash University, Clayton campus. The university acquired them after being asked to participate in the investigation of the collapse. It is said that they are to remind engineers of the consequences of their errors.

Commemorations have been held on 15 October every year since the collapse. A West Gate Bridge Memorial Park is located near the bridge. It opened on 15 October 2004, the 34th anniversary of the collapse. It includes the West Gate Bridge Memorial and Sculpture, and the memorial for six who died in the Spotswood sewer tunnel collapse of 12 April 1895.

Three other steel box girder bridges collapsed during their construction between 1969 and 1971: the Fourth Danube Bridge in Vienna on 6 November 1969; Cleddau Bridge (Milford Haven), Wales on 2 June 1970; and the South Bridge over the Rhine River in Koblenz on 10 November 1971. The UK government responded by setting up the Merrison Committee of Inquiry, headed by Sir Alec Merrison. The Merrison Committee provided an interim report in May 1971, and a final report in February 1973 on new design and workmanship rules for steel box-girder bridges.