Review article

The paper considers the elasticity modulus of wood as a composite material. Based on experimental data obtained by E. K. Ashkenazi and the elasticity theory of anisotropic body worked out by S. G. Lekhnitsky, theoretical research carried out by V. N. Glukhikh has proved interrelation of the constants of elasticity in the main directions of anisotropy. Namely, it is established that cylindrically anisotropic bodies at transition from the radial direction to tangential direction can have two or three extreme values depending on the ratios of the constants of elasticity. Thus, this fact is necessary to be taken into account at carrying out research of the constants of elasticity and the intense deformed condition of the elements of designs.