The Steel Triplets

I live in a city that has several world renowned landmarks aptly named after their location: the Sydney Opera House and the Sydney Harbour Bridge (the older of the two). I have found out that the Bridge is actually one of triplets! Many people see a similarity between the Tyne Bridge in the north of England and the Sydney bridge, however both were pre-dated by another in New York.

Hell Gate Bridge
What is now called Hell Gate Bridge in New York started life as the New York Connecting Railroad Bridge or the East River Arch Bridge. It was designed by Gustav Lindenthal, an emigre from what is now the Czech Republic. He had made a name for himself during the industrial expansion of the United States by designing and overseeing the construction of many public works and bridges. One of the earlier bridges he designed was Pittsburgh’s Smithfield Street Bridge built in the early 1880s.

It looks like he took that design and modified it for the East River in New York, using one arch instead of two and adding in masonry towers at each end to give it a classical look. He then added steel girders to “connect” the towers to the bridge because he feared that people would think that the bridge was not safe – they would assume that the towers were holding up the bridge.
Construction took four years from 1912 to 1916 and at the time it was the world’s longest steel arched bridge. It’s design was for purely rail usage and that has remained to this day.

Tyne Bridge
About 8 years after the Hell Gate Bridge was opened, the local Government in the north of England finally agreed to build the Tyne Bridge. As with many public infrastructure projects, it took decades to agree to start the work and a design house called Mott, Hay and Anderson (MHA) were given the job of designing the bridge. They had become experts in rail infrastructure and tunnels in the 20 odd years they had been operating. Their design is very similar to Lindenthal’s design in New York and there could have been some copying take place. David Hay, one of the partners of MHA had been to the US and written papers for the American Society of Civil Engineers. It is quite possible that he had met Lindenthal in the US and seen his bridge.

Construction started in 1925 and the work was awarded to Dorman Long, who eventually became Corus Steel in the UK. It was completed and the bridge opened for road traffic in 1928. The end towers were designed separately by a local architect to fit the environment and be used as warehouses, however the internal structures were never completed and as such were never used for their intended purpose. Granite stone from Cornwall was shipped up to build the towers.

Sydney Harbour Bridge
In parallel with the Tyne Bridge, the New South Wales Government in Sydney were looking for a design for a bridge across the harbour. Interestingly, like the Tyne Bridge, it took decades of public debate before a decision was made to build the bridge with the first ideas being raised over 110 years prior to work starting! It was 1914 when the bridge project started to gain momentum, however the money was redirected to the war effort. After the war, JJC Bradfield the Chief Engineer went on a world trip looking at bridges and decided that an arch bridge was the best design – he had seen Hell Gate Bridge in New York.

A tender was released in 1922 and 6 companies responded with 20 proposals. It was won by Dorman Long, presumably because they had evidence of building a similar bridge at that time, so awarding the tender to them gave Bradfield access to the MHA design which was lengthened to fit the gap!

Work started soon after the contract was awarded in 1924 with the concrete foundations for each end being laid in 2 years. In 1928 the arches were created and finished in 1930 with the final construction taking a further two years. The masonry towers like the original in New York were designed by a different architect as had also been the case in England. For this bridge they were made of concrete with a granite exterior sourced from a quarry south of Sydney. The bridge was stress tested and then officially opened in 1932 and is still used for rail and road traffic today.

It is an icon of the city just as it’s sisters are in New York and Newcastle.