Method of designing a corrugated sheet and corregated sheet obtained

Abstract

Method for designing a corrugated roofing sheet made of natural fibers, impregnated with bitumen including a uniform pattern of mutually parallel alternating corrugations borne by a mid-plane, the corrugations defining rounded crests each separated from the next by a rounded trough, the crests and trough being connected by alternately inclined portions, the transverse offset between two successive crests being equal to the transverse offset between two successive troughs and defining the pitch P of the corrugations, the sheet having a thickness E of material substantially constant over its extent, and a height H being twice the distance between the mid-plane and the exterior surface of a crest or twice the distance between the mid-plane and the exterior surface of a trough, these two distances being identical. The height, thickness and pitch values are determined by Fi<H/(8×E×(H+P))<Fs, where Fi=25 mm and Fs=35 mm.