Construction of Sydney Harbour Bridge: Asphalt and concrete

This clip would have been filmed around 1931 when the roadway and railway sections of the bridge were being completed.

Constructing the Sydney Harbour Bridge Synopsis

A comprehensive pictorial record that chronicles the construction of the Sydney Harbour Bridge between 1925 and 1931, filmed by the Paramount Film Service, Sydney.

Constructing the Sydney Harbour Bridge Curator's Notes

This extraordinary survey of the building of the Sydney Harbour Bridge, easily one of the country’s greatest engineering feats, reveals the sheer scale and enormity of the project. Aside from Commonwealth sponsored productions of the Bridge construction, it is probably the only comprehensive moving image record of the project as a whole. Certainly it is the longest running, at over 100 minutes in length.

Filmed over a six-year period, it covers the preliminary work and excavations of the site, the construction of retaining walls and abutments at the approaching ends of Dawes and Milson’s Points, the slow building and positioning of the steel arches, and the finishing touches such as laying the road and rail tracks.

Many people were employed on the project – not just the workers on the bridge, but steel workers, stonemasons and engineers. Important sections of this film document the associated steelworks, granite quarry and stone dockyards that supplied the building materials to the Bridge itself. The first fifty minutes of footage covers the years 1927-1929 and mostly details the excavations and the building of abutments and support beams. The selected clips come from the last half of the film and cover the later years, 1929-1931, when the major part of the bridge span was under construction and beginning to take its shape. The camera work is executed from various angles and filmed from both fixed and moving positions at different points along the bridge. There are also aerial shots that survey the Bridge in the context of the harbour and surrounding cityscape, and progressive views of the bridge at various points in its construction.

Historical records not only provide an image of the times, but a comparison with the present. For example the workers on the bridge who climb dexterously along its narrow beams high above the waters below, wear almost no safety equipment and seem to defy both gravity and chance as they carry out their work. It is astonishing to think that only a handful of the workers perished during the Bridge’s construction given these conditions. A short section of this film also shows workmen doggedly battling rough seas in an unfriendly harbour!

The bridge was completed in 1931 and was, according to this documentary, ‘one of the greatest British engineering feats dominating the skyline’ in the British Empire. But while it may have been a great achievement for the British engineers and for the British Empire, the Sydney Harbour Bridge was undoubtedly Australia’s own. The National Film and Sound Archive holds a number of film prints of Construction of Sydney Harbour Bridge deposited from various private and public sources. The Paramount Film Service also filmed a newsreel special of the official opening of the Sydney Harbour Bridge in 1932.

Notes by Poppy De Souza.

Education notes

This clip shows the final stages in the construction of the Sydney Harbour Bridge in 1931 – the completion and sealing of the Bridge deck. The clip opens with the asphalt road surface being prepared. The next scene shows the appearance of the deck before concreting and asphalting, followed by scenes of concrete being made onsite, moved, poured and finished off. The last two scenes show the ironbark sleepers for the railway tracks being prepared and a view of the unfinished pedestrian walkway. Intertitles are used to explain what is shown to the audience.

Educational value points

• The Sydney Harbour Bridge was one of the greatest bridge-building projects undertaken anywhere in the world in the late 1920s and early 1930s. With a deck 1,149 m long and 48.8 m wide, it remained the widest long-span bridge until the 2012 opening of the Port Mann Bridge in Canada. About 1,400 men worked on constructing the Bridge and, within nine months of closing the arch, the workforce had finished the immense deck, ready for laying the roadway and the railway and tramway tracks.

• Progress in bridge-building technology combined with advances in Australian manufacture of reinforced concrete and prefabricated steel turned the idea of a bridge across Sydney Harbour from a dream into a reality. The New South Wales Government first began to consider building the bridge at the beginning of the 20th century and finally decided to proceed in 1922. Construction commenced in 1924 and the completed Bridge opened on 19 March 1932.

• High levels of innovation were required for this technically demanding project and the deck was no exception. Originally developed by Dr JJC Bradfield (1867–1943), the design of the Bridge called for 42 hangers to be erected on either side of the arch to carry the deck. Lifting the prefabricated hangers, which ranged in height from 7.3 m to 58.8 m, called for the construction of a specially designed cradle.

• As the Bridge neared completion in 1931 popular excitement grew, fuelled by almost daily newspaper reports, photographs and films such as this one explaining how the Bridge fitted together, piece by piece. The public learnt how the arch held the hangers, which in turn held huge steel beams across the width of the Bridge. The beams held the trimmers, narrow lengthwise beams that formed the base for the concrete of the deck and the asphalt of the road.

• The 1924 tender for the Bridge was one of the first issued for a major infrastructure project in Australia that specified that materials had to be sourced and manufactured locally where possible. Kandos Cement Ltd in central NSW was one company that benefited. The 1924 contract to supply the Bridge with concrete ensured the company’s survival and expansion of its technical capacity. Some 95,000 cubic m of concrete was used in the Bridge.

• There were relatively few machines on the Bridge and its deck was built by hard physical labour, starting at the centre and moving outwards. The clip shows almost every stage of asphalting and concreting being done by hand. There were just two 1-cubic-yard- (0.76-cubic-m-) capacity concrete mixers in use, one for the north gang and one for the south, with 12 concreters working in each gang – six would mix and push the loaded wagons and six would concrete.

• The Bridge reflects the major changes in transport that occurred from the 1920s onwards. Originally conceived as more of a rail bridge than a road bridge, at first it had two rail tracks on each side, with trains running on the western side and trams on the eastern side. With the demise of the city’s tram system in the 1950s, the tram tracks were converted for road traffic, which has since grown from 10,900 vehicles a day in 1932 to about 160,000 in 2007.

• The scenes in this clip are typical of the silent industrial documentary film genre in which the intertitles briefly introduce a particular process but the images carry the weight of description. In the clip, panning and medium-distance shots set the scale and show the process as a whole. These are interspersed with close-ups of tools in use and machines in operation, including a rare tracking shot achieved by mounting the heavy camera on one of the concrete wagons.

Education notes provided by The Learning Federation and Education Services Australia