The Millau Viaduct and The Hampden Bridge

The Millau Viaduct Connects two limestone plateaus (the Causse du Larzac and the Causse Rouge), crossing above the Tarn valley below, who’s small winding country roads around the town of Millau used to be heavily congested in holiday seasons as it was the only way across the valley. The Bridge is situated in the communes of Millau and Creissels, in the south of France.

The Millau Viaduct is the final link in the A75 AutoRoute, a superhighway which stretches from Clermont-Ferrand to Pezenas. This is a large, continuous highway where cars can travel at speeds exceeding the normal speed limit, and is long and straight, allowing cars to travel right though France directly and quickly.

The Millau Viaduct is the tallest suspension bridge in the world, with its tallest pylon measuring to 343 m height, and total weight measured at 242,000 tonnes. The road itself stretches for 2.46km and is 280m above the valley floor. The weight of the road deck is a whopping 36,000 tonnes. The steel road deck, 4.2m thick, has a width of 32m, wide enough for two lanes of traffic in each direction. The total amount of concrete used on the structure was 205,000 tonnes.

One of the great engineering feats when building this bridge was the use of steel. Despite its maximum height of 343m span of 2.46km, 280m above the valley floor, the bridge is actually quite light. 242,000 tonnes seems like a lot but without the use of steel on the structure, this bridge would have been more than twice as heavy. Steel is a much stronger material than concrete, so can support more weight with less mass. The actual road deck, which is comprised almost entirely of steel, only weighs 36,000 tonnes. The other 206,000 tonnes comes primarily from the massive pylons, which are m...

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...was reduced, and the bridge was guaranteed a longer life.

The Hampden Bridge was built to replace the Wagga Wagga company bridge, a toll bridge that was constructed in 1862. The Hampden bridge was built as it would provide the main and one of the only links between North Wagga Wagga South Wagga Wagga, which were divided by the Murrumbidgie river.

The Hampden Bridge was a great advantage the community of Wagga-Wagga as it enabled quick easy access over the Murrumbidgie River so as to cross from North to South Wagga Wagga.

Some of the disadvantages of the bridge were that after 100 years of use, in 1975, the bridge was starting to fall apart and eventually, after a few years, the maintenance cost of the structure was starting to get to high so the Wagga Wagga council closed the bridge, and currently there are plans in place to demolish the bridge in the future.