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Dr. JCC Bradfield, who designed the Sydney Harbour Bridge, also designed Brisbane's Story Bridge. The steelwork of the approaches to the latter (above) closely resembles that of the approaches to the Sydney Harbour Bridge (right).


Sydney Harbour Bridge Look-alikes

The HellGate Bridge (above) over the East River in New York City is considered to be one of the world's most beautiful bridges. The crowning achievement of late 19th century bridge designer Gustav Lindenthal, the span was not only the world's heaviest and longest steel arch bridge when completed in 1917, it was the inspiration for the Sydney Harbour Bridge.

The Tyne Bridge (above), the most famous of the ten bridges that cross the River Tyne between Newcastle and Gateshead, is strikingly similar to the Sydney Harbour Bridge, especially in this photograph. It was the largest single span in the world until the Sydney Harbour Bridge was completed four years later. Opened on 10th October 1928 by King George V, it was built by Dorman Long of Middlesbrough, the same company that built the Sydney Harbour Bridge. They used the Tyne Bridge as a 'test run' for the much larger Sydney bridge.

The Silver Jubilee Bridge or Runcorn Bridge (above) crosses the River Mersey and the Manchester Ship Canal at Runcorn Gap between Runcorn and Widnes in Cheshire, England. It is a through arch bridge with a main arch span of 1,082 feet (330 m). It was opened in 1961 as a replacement for the Widnes-Runcorn Transporter Bridge, and was initially known simply as the Runcorn Bridge or Runcorn–Widnes Bridge. In 1975–77 it was widened, after which it was given its official name in honour of the Queen's Silver Jubilee. It carries the A533 road and a cantilevered footway. The bridge has been designated by English Heritage as a Grade II listed structure. The bridge was built in 1961 by Dorman Long & Co., the company which built the Sydney Harbour Bridge.

The ChaoTianMen arch bridge (above) crosses the Yangtze river in the city of Chongqin in South West China. It has a tied arch main span of 552m with continuous side spans of 190m, and has been designed to resemble the Sydney Harbour Bridge, completed by Dorman Long & Co. in 1932. DLT are acting as consultant to the main contractor, 2nd Navigation engineering Bureau and are responsible for developing and detailing the construction method to be used. On completion this will be the longest arch span in the world, a record currently held by the Lupu bridge in Shanghai (550m).


Sydney Harbour Bridge

Acclaimed as one of the most remarkable feats of bridge construction in the world, at the time it was built and until recently it was the longest single span steel arch bridge in the world and is still in a general sense the largest.
Plans for a bridge linking north and south had been mooted since the settlement of Sydney began. The diary of First Fleeter William Dawes refers to conversations he had with Governor Phillip about the need for a bridge linking the two shores. In 1815, government architect Francis Greenway, in a report to Governor Macquarie, proposed the building of a bridge from Dawes Point at the city's edge to the northern shore, however it was not until 1922 that legislation was passed and acted upon, authorising the construction of a bridge.

Ninety nine years after Greenway presented his proposal to the Government of the day, Dr. JCC Bradfield, the NSW Government's Chief Engineer, was sent to Europe to investigate the latest engineering technology involved in bridge and underground railway construction. With an idea of what was required, he returned to Europe in 1922 to seek tenders for the construction of a harbour bridge. His plans and specifications allowed the alternatives of a cantilever bridge or an arch bridge.
Twenty proposals were received from six different companies for various types of design, including suspension bridges not covered by Dr. Bradfield's specification. The tender of Dorman Long and Co. Ltd., of Middlesborough, England for an arch bridge was accepted, the design being substantially in accordance with one of Dr. Bradfield's proposals. The detailed design was carried out by the Contractor's Consulting Engineer, Sir Ralph Freeman, and the fabrication and construction were under the direct charge of Mr Lawrence Ennis, a director of the firm. The design and the construction of the bridge were supervised at all stages by Dr. Bradfield and his staff.
The first sod was ceremoniously turned on the site of the North Sydney Railway Station on 28th July 1923. The acquisition and demolition of buildings in the path of the new bridge and its approaches on both the northern and southern shores commenced on 28th July 1924. The excavations for the foundations of the main bearings and approach span piers commenced in January 1925. While the approach spans were being built, the foundations on either side of the harbour were prepared to take four steel bearings (right) consisting of large hinge pins and massive steel bases for support of the arches.
At each end of the arch span of the bridge, and just behind the bearings, large abutment towers supporting the pylons were constructed. The abutment towers with the pylons are not a necessary structural feature of the bridge. They do not support the arch and were built principally to enhance the appearance of the structure. The approach spans were constructed from the inshore ends towards the harbour, and their ends rest on their respective abutment tower. The arch was constructed in two halves, holding each back with steel cables anchored in large U-shaped tunnels dug into the rock. After the approach spans and abutment towers had been constructed at deck level, work began on the main arch. Giant creeper cranes were built and assembled on temporary ramps on the abutment towers. As the first sections of the arch were built, the cranes moved across onto the sections and erected the second section, before creeping on and building the next section.
On 7th August 1930, the erection of the arch was completed and work began on joining the two sections. The steel cables were slackened in a process that required round the clock supervision. At 10 pm on 19th August the two halves were linked and the north and south were joined for the first time. The cables were removed after stress testing was carried out and thus the arch was converted to a two hinge structure. The deck, which is hung from the arc of the arch itself, was constructed from the centre of the bridge outwards. All steelwork for the deck was completed in May 1931. Two railway lines were laid on either side of the hangars, the vehicles lanes placed in the middle of the deck with footways located on the extreme outside. As the erection of the steelwork was proceeding, the approaches were being constructed, including Milsons Point and North Sydney railway stations, and roadway approaches on both sides of the harbour.
The bridge was opened to roadway, railway and pedestrian traffic by the then Premier of New South Wales, Mr JT Lang, on Saturday 19th March 1932. The time taken to complete the whole work, including bridge and approaches was eight years. The contract for the bridge construction provided for six months' maintenance by the contractors from the date of opening, after which maintenance became the responsibility of the State. Built at a cost of $20 million, it was only paid off in 1988, much of the cost being raised by tolls placed on vehicular traffic using the bridge. Tolls collected after the bridge was paid for has gone towards the cost of the construction of the harbour tunnel.
At the times of its construction, the Bridge was seen as a symbol of Australia's industrial maturity. It was the catalyst for the development of the North Shore. Along with the city underground railway system which was built simultaneously with it, the Bridge is the most important event in the development of Sydney's transport system and has been in continuous use as such for over 60 years. It is Dr. Bradfield's crowning achievement, on which he spent more than half his working life. The credit for the realisation of the Bridge is also due to the contractors Dorman Long and to the English engineer Sir Ralph Freeman. It was Freeman's finest bridge but his contribution was marred by the famous dispute with Bradfield over who was the designer.
Although subsidiary to the bridge itself and of less engineering interest, the approaches are an integral part of the bridge construction, an achievement of outstanding, international significance. It was on the northern and southern approaches that the Bridge was officially opened, the largest crowd ever seen in Sydney assembled. The viaducts, tunnels and bridges incorporated into the approaches are essential components of the most important single event in the development of Sydney's transport system. They are a part of Bradfield's greatest achievement and, although less glamorous than the steelwork of the Bridge itself, they are the parts for which he was wholly and directly responsible.
The Bridge itself is an engineering design and technical achievement of international importance. It terms of its span it ranks third in the world but it's reputation as the world's greatest steel arch rests on its combination of span, width and load bearing capacity, and for the difficulties overcome in its erection. Bradfield's design of the arch and pylons was closely based on New York's HellsGate Bridge, opened in 1917. The span, however, was 205 m longer than the American bridge and it contains the heaviest steelwork of its kind ever constructed.
Reinforced concrete technology in NSW was still in its infancy in the 1930's and the approach arches, slabs and retaining walls are important examples of its use. The urban viaducts formed by the Approaches are rare in NSW. The unpainted, rendered retaining walls, pilasters and parapets of the approaches are distinctive and intact examples of inter-war stripped classical design. They represent a continuation of the previous work on the electric railway using render instead of sandstone as a more economical facing material.
The bridge is a two hinged steel arch, with a steel deck hanging from the arch and five steel truss approach spans leading to the arch. The arch is hinged at the base on each side of the harbour, the hinges allowing expansion and contraction and take the full weight of the bridge through large solid sandstone skewbacks. 63% of the steelwork of the arch is needed to support the deadweight of the bridge itself, 25% for the live load, 5% for wind pressure (it can withstand winds up to 200 km/hr.), 5% for the effect of temperature (it can stand temperature variations of 49 degrees Celsius) and 2% for the braking of trains.
15,300 cubic metres of masonry was required to line the bridge supports and pylons. This was quarried at Moruya in NSW, 30 km south of Sydney. 42,000 cubic metres of rock and dirt were excavated just to make way for the Bridge Fabrication Shops. The bridge was constructed by 4 x 25 tonne creeping cranes. The concrete footings for the four bearings upon which the Bridge sits are 12 metres deep. The bearings weigh 300 tonnes each. 105 sliding bearings and six million rivets were used in building the bridge. It was designed to handle a maximum traffic flow of 6,000 motor vehicles per hour. During today's rush hours, the bridge handles up to 15,000 vehicles per hour.
52,000 tonnes of steel were used in the building of the Bridge. At any given time during the seven years it took to build, 1,400 people were employed in its construction. 33,600 litres of paint are needed to give the bridge one coat. It is in the continual process of being painted in order to combat corrosion. Span: 503m. The contract price for the bridge was £4,217,721/11/10. More >>

Sydney's Miniature Harbour Bridge

A well known landmark on the Hume Highway near the Sydney suburb of Liverpool, a miniature version of Sydney's Harbour Bridge stands proudly at the entrance to the premises of motor dealer Peter Warren. First used in a display during half time at the 1987 Rugby League Grand Final at the Sydney Cricket Ground, it was built and assembled by apprentices from Garden Island.
Peter Warren, who was at the Grand Final, decided to purchase it and have it transported and erected at the front of his Warwick Farm motor dealership where it now stands. Numerous engineering modifications had to be carried out to comply with various statutory requirements, eg. road clearance to the bottom of the span to allow semi-trailers etc. to access the dealership under it.
The bridge was officially opened on Sunday 7th February 1988 and was Peter Warren's contribution to the Australian Bicentenary celebrations of 1988. Due to public response and the fat that it became such a recognisable landmark during 1988, permission was sought and eventually granted by all necessary authorities to allow the bridge to remain for perpetuity.

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