US bridge 'design issue' detected (BBC)

[eppur_se_muova]

US investigators have found a possible "design issue" in the bridge that gave way over the Mississippi river.

The parts causing concern are the steel plates that connect girders.

Federal officials have urged states to carefully consider the additional weight placed on bridges during construction or repair projects.
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But safety officials have found a "design issue" with what are known as gusset plates - the steel connectors that tie together the angled steel beams of the bridge's frame - at particular locations on the bridge.

Investigators are trying to verify the loads and stresses on the gusset plates and the material used to make them.
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more: http://news.bbc.co.uk/2/hi/americas/6938245.stm

Apologies if dupe -- I hadn't seen anything about this posted yet.