Our study focuses on modeling the macroscopic anisotropy of fatigue limit in fully reversed loading of two tropical wood species, Azobe (Lophira alata Banks) and Bilinga (Nauclea diderrichii Merr.). The proposed formula for modeling anisotropy from the orthotropic directions of wood is a rewrite of a symmetry plane formula (R, T) to the plane of symmetry (L, R). This formula requires the knowledge of three parameters: the fatigue limit in fully reversed loading at 0°, the fatigue limit in fully reversed loading at 90° and the shear modulus in the plane (L, R). A discussion of the acuteness of the formula is made in relation to the literature through its graphical representation

Keywords : Fatigue Limit. Symmetrical Alternating Traction. Anisotropy. Bois.