Overview of orthotropic viscoelastic mechanosorptive models for wood

Wood is one of the most widely applied engineering materials due to its favourable physical and mechanical characteristics. As an inhomogeneous biomaterial, wood exhibits complicated mechanical properties including anisotropy, elasto-plasticity, viscoelasticity, and hygroscopic characters. To analyse the time- and moisture-dependent behaviour of timber structures, both mechanical loading and moisture evolution has to be taken into account. This study analyzes the capability and limitations of different rheological models. A 3D-orthotropic viscoelastic, mechano-sorptive model for wood is presented here, which covers the timber behavior under varying moisture condition during loading and unloading phases.