A microcell-based constitutive modeling of cellulose aerogels under tension

• Published in: Acta mechanica Vol. 229; no. 2; pp. 585 - 593
• Main Authors: Rege, Ameya, Itskov, Mikhail
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.02.2018; Springer; Springer Nature B.V
• Subjects: Aerogels; Analysis; Beam theory (structures); Cellular biology; Cellulose; Classical and Continuum Physics; Control; Dynamical Systems; Engineering; Engineering Thermodynamics; Euler-Bernoulli beams; Heat and Mass Transfer; Kinematics; Morphology; Original Paper; Solid Mechanics; Tension; Theoretical and Applied Mechanics; Vibration; Walls
• ISSN: 0001-5970; 1619-6937
• DOI: 10.1007/s00707-017-1987-0

Cellulose aerogels are characterized by a cellular morphology. The mechanics of such materials is largely dictated by the behavior of their cell walls. Under tension, these aerogels undergo only small strains while their cell walls are subject to combined bending and tension loading. Accordingly, in the present paper, we describe the kinematics of these cell wall fibrils based on the Euler–Bernoulli beam theory. The microscopic damage criterion is based on the normal stress in the cell walls. Variation in the sizes of the microcells is accounted for by using the pore-size data from experiments. The so-resulting constitutive model includes few micromechanically motivated material parameters, shows very good agreement with our own experimental data of cellulose aerogels, and also accurately predicts material failure under tension.