The concrete is often made with foam, fly-ash or other waste materials to make it lighter as well as cheaper.

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While most of the freight will have been flown straight on from last weekend's season-opener in Qatar, the cloud of ash has created a no-fly zone over much of northern and central Europe and made it impossible for many team personnel to reach Japan.

BBC: Volcanic ash cloud forces postponement of Japan MotoGP

The UK is enduring a fourth day as a virtual no-fly zone, as the travel chaos caused by volcanic ash drifting from Iceland shows no sign of ending.

BBC: Volcano cloud threatens Formula 1 preparations

But the no-fly zone still applied to most of Britain, and a new cloud of volcanic ash was reported to be on its way.

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