Bridges across US inspected following collapse

Inspectors are set to check 700 bridges across America in the wake of the collapse of the 1-35W bridge in Wednesday evening. Four people are confirmed dead and 30 people are listed as missing in the wake of the collapse.

The checks, on similar steel truss bridges, come as more details about the state of the Minneapolis structure emerged in the last day. A check on the bridge in 2005 found that it was structurally deficient but not in such as bad state as it needed to be taken out of operation.

Keith Eaton, chief executive of the UK's Institution of Structural engineers, told the BBC that such collapses, which are extremely rare, happen either because the load is too heavy, or the connections between the bridge's structural elements are too weak.

"The engineers will have to see where the collapse started. Clearly a failure occurred somewhere which imbalanced the whole thing," he said.

Leading US architect Rafael Vinoly said he was not surprised by the collapse as there was a widespread lack in investment in infrastructure in the US.

Speaking on the BBC’s Newsnight show last night Vinoly, who is the architect of the new Walkie Talkie tower in the City of London, said: “There has been a lack of serious investment infrastructure for too long. The public take such structures for granted.”