Corrugated Iron

Corrugated galvanised iron is a lightweight building material composed of sheets of hot-dip galvanised mild steel, cold rolled to produce a linear corrugated pattern in them. The corrugations increase the bending strength of the sheet in the direction perpendicular to the corrugations, but not across them. Normally each sheet is manufactured longest in its strong direction.

WIKIPEDIA ENTRY FOR CORRUGATED IRON

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