It’s quite a claim to fame for England to be able to say that it is home to the first cast-iron bridge in the world – Iron Bridge, which was completed in 1779 and opened to traffic in 1801. And to think that it is still standing today after more than 150 years of service, an icon of Great Britain’s industrial history, is incredible.
Make your way to Shropshire and you’ll be able to see it for yourself. It was finally closed to vehicles in 1934, declared an Ancient Monument and named as a UNESCO World Heritage Site in 1986.
The mass production of cast iron was made economically viable in 1709, in the village of Coalbrookdale by one Abraham Darby, who would go on to become the first of many distinguished iron masters.
He used coke made from local coal in fuel furnaces instead of charcoal, a real breakthrough for production, driving Britain’s iron trade and giving local industry a serious boost.
This increase in productivity locally meant that there was soon a need for a bridge to make crossing the wooded gorge a possibility, so goods could be transported over the River Severn.
Shrewsbury-based architect Thomas Farnolls Pritchard had the idea in 1773 to build the world’s first iron bridge, bringing together engineering skills and new iron casting techniques – a bridge to connect the parishes of Benthall and Madley over the river, one of the busiest in the country.
So that’s the (condensed) story of how the Iron Bridge came into being – but how has the structure itself fared over the years and how is it being maintained so it doesn’t fall into ruin?
In 2017, English Heritage started a crowdfunding campaign to help secure the future of the bridge, with years of detailed analysis carried out to find out as much as possible about how it functions.
Different elements of the bridge needed to be replaced, including the iron radials and braces holding it together, the main iron arch, and the deck plates and wedges. It also needed to be repainted and the road surface restructured to help protect it from the elements.
Corrosion can have a serious effect on metal, leading to a loss of strength in structural components. It can also have an impact on the fatigue strength of steel elements and connections, so it’s important that maintenance work is carried out regularly on structures and any repairs carried out as soon as possible.
Seek expert advice on corrosion control solutions if you’re unsure as to whether any of your structures are starting to show signs of wear and tear. Prevention is always better than cure, so give us a call if you’d like to arrange a feasibility study to assess and prioritise any repair requirements.