Falk K. Wittel

Hygroresponsive materials exhibit a complex structure-to-property relationship. The interactions of water within these materials under varying hygric and mechanical loads play a crucial role in their macroscopic deformation and final application. While multiple models are available in literature, many lack a comprehensive physical understanding of these phenomena. In this paper, we introduce a stick-slip fiber bundle model that captures the fundamental behaviors of hygroresponsive materials.

Properties P i as function of moisture ω as found in Refs [ 14 ] and [ 15 ]. The moisture interval [8%, 18%] roughly corresponds to a relative humidity range of [35%, 85%] (adsorption at 85% and desorption at 35%). Considering Hooke’s law in three dimensional Euclidean space σ = Cε , a strain-state ( ε = ε kl e k ⊗ e l ) is mapped onto a stress state ( σ = σ ij e i ⊗ e j ) by a 4 th -order stiffness tensor C ( C = C ijkl e i ⊗ e j ⊗ e k ⊗ e l ).