The AP1000's shield building consists of a concrete layer, sandwiched between thick steel plates.

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In Afghanistan, the foam would be wrapped in a low-tech layer of chicken wire, then covered in a thin layer of concrete.

BBC: Aftermath of 1998 quake in northern Afghanistan

Careful observers gained pleasure in a whole other layer of knowledge--less concrete, but more tantalizing--by watching the interaction of speaker and audience.

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