STRESS OF CORRUGATED FIBERBOARD MADE BY COMPRESSION UNDER UNIFORM BENDING OF MOMENT AXIS IN MACHINE DIRECTION (ON SINGLE WALL FIBERBOARD WITH SYMMETRICAL THICKNESS STRENGTH)

We investigated stress generation in a semichemical corrugated medium (SM) by compressional forces under uniform bending with the bending mo ment axis of the machine direction (MD) in single-wall corrugated fibe rboard (SWCF), and attempted to derive an elastic expression for its g eneration stress sigma(sp). Using this expression, the analysis of sig ma(sp) was carried out. Values of the lateral force W-sx and fixed mom ent M(50) per unit length at the joint between kraftliner (KL) and SM are determined, and relationships between those values and the shape o f SWCF are considered. The following results are obtained from the exp ression. The maximum value sigma(pmax) of sigma(sp) is found at the jo int on the outer surface of SM. W-sx, M(50) and sigma(pmax) increase m arkedly with the increase of wavelength L and decrease markedly with t he increase of wave height h for SM.