3D hygro-mechanical meso-scale model for wood

Wood is rather complex organic material, which has been in the past widely used not only in many engineering structures but also in cultural heritage objects such as sculptures, paintings, etc. Due to its hygroscopic nature, wood is greatly sensitive to the change of moisture content, mainly induced by the changes of the air temperature and relative humidity. Exposure of these objects to aggressive environmental conditions, together with mechanical actions, can lead to deterioration and ultimate destruction. In the present study, a 3D hygro-mechanical meso-scale model for wood is formulated and implemented into the 3D finite element code MASA. The proposed coupled model, consisting of mechanical and non-mechanical part (transport of moisture), is validated against experimental tests available in the literature, confirming its suitability for realistic modeling of wood. The proposed model can be used for the main degradation phenomena (i.e. cracks due to moisture gradients, delamination), which are generated by different environmental and/or mechanical loading conditions. This numerical tool provides useful support for damage analysis of new or existing cultural heritage objects and can help in their preservation.