Calculation of elastic properties of natural fibers

This article deals with the calculation of the elastic properties of cellul ose based natural fibers by using two different types of idealization and a ssumptions. One model (model A) bases on antisymmertrical laminated structu re, while the second one (model B) bases on a thick laminated composite tub e model. Model B is able to take into account the elliptic geometry, the ho llow based structure of the cross section of the fiber cell. The calculated relationships between spiral angle and modulus in fiber axis by model A fi ts successful experimental data for holocellulose fibers which were publish ed elsewhere. In general, modulus in fiber axis decreases with increasing s piral angle as well as the degree of anisotropy, while shear modulus reache s a maximum for a spiral angle of 45 degrees. Fiber cell modulus increases linear with increasing cellulose content for both, the calculated (model A) and measured values. The correlation between experimental data and calcula tion ones was not as high as in the case of modulus versus spiral angle. Th e discrepancy between model A and a more real cross section is calculated ( model B) with roughly 30%. (C) 2001 Kluwer Academic Publishers.