Résumé
Wood is present in many cultural heritage objects in Japan thanks to its capacity to resist over long period of time. However, the evolution of its properties in regular use remains insufficiently known. The present study on the effect of wood aging takes advantage of the Japanese context where building traditions have been maintained for centuries. 3 points bending test were performed in longitudinal (L) and radial (R) directions on small clear wood specimens cut from 8 historical samples and one modern reference considered of high quality by craftsmen. Although aged wood appeared more rigid and stronger than recent wood, after density and humidity corrections were applied no significant variation of L and R rigidity or L strength was observed. The post-linear behaviour, however, was drastically influenced by wood age especially in R direction where the strength and rupture energy decreased markedly with the time elapsed since the wood was processed. Aged wood can be considered as safe as long as it is not loaded perpendicular to grain.